Internet-Draft Matt Mathis
John Heffner
Pittsburgh Supercomputing Center
Rajiv Raghunarayan
Cisco Systems
TCP Extended Statistics MIB
draft-ietf-tsvwg-tcp-mib-extension-08.txt
Sun Oct 23 12:48:11 EDT 2005
Status of this Memo
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This Internet-Draft will expire April 23, 2006
Abstract
This draft describes extended performance statistics for TCP. They
are designed to use TCP's ideal vantage point to diagnose performance
problems in both the network and the application. If a network based
application is performing poorly, TCP can determine if the bottleneck
is in the sender, the receiver or the network itself. If the
bottleneck is in the network, TCP can provide specific information
about its nature.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . 2
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2. The Internet-Standard Management Framework . . . . . . . . 4
3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . 4
4. TCP Extended Statistics MIB . . . . . . . . . . . . . . . . 8
5. Normative References . . . . . . . . . . . . . . . . . . . 58
6. Informative References . . . . . . . . . . . . . . . . . . 59
7. Security Considerations . . . . . . . . . . . . . . . . . . 59
8. Contributors . . . . . . . . . . . . . . . . . . . . . . . 60
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 60
10. Authors' Addresses . . . . . . . . . . . . . . . . . . . . 60
11. Intellectual Property . . . . . . . . . . . . . . . . . . 61
12. Disclaimer of Validity . . . . . . . . . . . . . . . . . . 61
13. Full Copyright Statement . . . . . . . . . . . . . . . . . 62
1. Introduction
This draft describes extended performance statistics for TCP. They
are designed to use TCP's ideal vantage point to diagnose performance
problems in both the network and the application. If a network based
application is performing poorly, TCP can determine if the bottleneck
is in the sender, the receiver or the network itself. If the
bottleneck is in the network, TCP can provide specific information
about its nature.
The SNMP objects defined in this draft extend TCP MIB, as specified
in RFC 4022 [RFC4022].
This document is automatically generated from a database of potential
TCP instruments. Beware that the OIDs are still likely to change
with future versions. The most current version can be obtained from
http://www.web100.org/mib/ . Please use tsvwg@ietf.org to send
comments to the entire TSV WG.
X. Changes
This virtual section will be removed as the draft nears completion.
Changes since draft-ietf-tsvwg-tcp-mib-extension-07.txt (20-Feb-2005)
Added tcpEStatsStackSpuriousRtoDetected. Renamed AckAfterFR to
tcpEStatsStackSpuriousFrDetected and clarified the description.
Restructure the tables yet again. The perf, path, and stack tables
now each start out with some required objects, followed by optional
objects. This permits a much more logical grouping of instruments,
lowers the cost for a minimal implementation and encourages
incremental deployment.
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Changes since draft-ietf-tsvwg-tcp-mib-extension-06.txt (20-Feb-2005)
Added tcpEStatsPerfPipeSize and tcpEStatsPerfMaxPipeSize to detect
when TCP is unable to open the window as large as permitted.
Added tcpEStatsStackInRecovery to indicate if the connection is
currently in recovery (e.g. has outstanding retransmissions), or
about to enter recovery.
Move tcpEStatsPerfSumRTT, Tcpestatsperfhcsumrtt and
tcpEStatsPerfCountRTT to the path table, tcpEStatsPath.
Added tcpEStatsPathHCGroup.
Move tcpEstatsPathAckAfterFR and tcpEstatsPathSndDupAckEpisodes back
to the performance table, tcpEStatsPerf.
Move tcpEStatsPerfSampleRTT, tcpEStatsPerfSampleRTT and
tcpEStatsPerfSampleRTT to the stack table, tcpEStatsStack.
Clarified the descriptions of tcpEStatsPerfDupAckEpisodes,
tcpEStatsPerfDupAcksOut and tcpEStatsPerfCongSignals
Changes since draft-ietf-tsvwg-tcp-mib-extension-05.txt
(17-July-2004)
Many changes to object descriptions MIB comments and overview to
improve clarity.
Completely restructured the per connection tables. Seven table were
reduced to five. The main per connection table tcpEStatsPerfTable
is now mandatory. Three other new tables are focused on
understanding the details of the behavior of the path, internal TCP
algorithms and the application. In addition, there is a new tuning
table with per-connection writable controls to work around a number
of common problems. Note that due to the table restructuring, most
of the object names listed below have changed.
Restructured the Listen Table (tcpEStatsListenerTable) to better
instrument various SYN flood defenses.
Removed minimal receiver window objects, and replaced them by the
count of the number of transitions to zero window from non-zero
window.
Replaced tcpEStatsPathIpTos by tcpEStatsPathIpTosOut and added
tcpEStatsPathIpTosIn.
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Updated the descriptions of tcpEStatsDataSndNxt, tcpEStatsDataSndMax,
tcpEStatsDataThruOctetsAcked, tcpEStatsDataHCThruBytesAcked,
tcpEStatsDataThruBytesReceived, tcpEStatsDataHCThruBytesReceived,
consistiently use RFC791 variables (SND.NXT, etc) or refer to other
TCP-ESTATS-MIB objects.
Changed tcpEStatsSynOptsMSSSent and tcpEStatsSynOptsMSSRcvd from
Gauge32 to Unsigned32
Updated descriptions of tcpEStatsConnectLocalAddress and
tcpEStatsConnectRemAddress to new conventions for InetAddress
[RFC4001]
Changes since draft-ietf-tsvwg-tcp-mib-extension-04.txt (27-Oct-2003)
Updated ID boiler plate to RFC3668, ID-Guidelines and fixed some
formatting glitches
Added a Table of Contents
Updated the description of tcpEStatsConnectionState to indicate that
the listen state included only for document parallelism and should
not be used.
Explained why it is useful for tcpEStatsConnectIdTable and others to
remain for 30 seconds after a connection closes (so you retrieve the
total statistics for the entire connection).
Added comment about not supporting writing DeleteTcb into the TCP
State.
Explained that SndNxt is not a counter because it is non-monotonic.
Clarified StartTime to be row creation
Clarified row creation to be at the first SYN unless techniques to
defend against SYN floods are in effect, then at connection
establishment.
Added tcpEStatsControlNotify to control the generation of
notifications.
Changed sequence numbers from ZeroBasedCounter32 to Counter32.
Changes since draft-ietf-tsvwg-tcp-mib-extension-03.txt (2-Mar-2003)
Replaced "queued" with "buffered by TCP"
Changed all counters in the TCP connection tables to be ZeroBased
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Remove tcpEStatsHCInSegs, tcpEStatsHCOutSegs, which appear in as
tcpHCInSegs and tcpHCOutSegs in draft-ietf-ipv6-rfc2012-update-03.txt
and later drafts.
Added changes section.
2. The Internet-Standard Management Framework
For a detailed overview of the documents that describe the current
Internet-Standard Management Framework, please refer to section 7 of
RFC 3410 [RFC3410].
Managed objects are accessed via a virtual information store, termed
the Management Information Base or MIB. MIB objects are generally
accessed through the Simple Network Management Protocol (SNMP).
Objects in the MIB are defined using the mechanisms defined in the
Structure of Management Information (SMI). This memo specifies a MIB
module that is compliant to the SMIv2, which is described in STD 58,
RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580
[RFC2580].
3. Overview
The TCP-ESTATS-MIB defined in this memo consists of 6 tables,
two groups of scalars and two notifications:
- The first group of scalars in this MIB contain a statistic
of a TCP protocol engine not covered in RFC 4022. The
scalar tcpEStatsListenerTableLastChange, provides management
stations with an an easier mechanism to validate their
listener caches.
- The second group of scalars consist of knobs to enable and
disable information collection by the tables containing
connection-related statistics/information. For example the
tcpEStatsControlPath object controls the activation of the
tcpEStatsPathTable.
The tcpEStatsConnTableLatency object determines how long
table rows are retained after connection close, to permit
reading final connection completion statistics.
Changing any of these controls may affect the correctness of
other management applications accessing this MIB. Generally
local policy should only permit limited write access to
these controls (e.g. only by one management station or only
during system configuration).
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- The tcpEStatsListenerTable provides information on the
active TCP listeners on a device. It supports objects to
monitor and diagnose SYN-flood denial-of-service attacks as
described below.
- The ZeroBasedCounter32 and ZeroBasedCounter64 objects
in the tcpEStatsListenerTable and tcpEStatsListenerTable
are initialized to zero when the table row is created.
- The tcpEStatsConnectIdTable provides a mapping between the
connection indices i.e. source address type, source address,
source port, destination address type, destination address and
destination port, and the connection index. The connection
index is used to index into most of the remaining tables in this
MIB module, and is designed to facilitate rapid polling of
multiple objects associated with one TCP connection.
- The tcpEStatsPerfTable contains objects that are useful for
measuring TCP performance and first check problem diagnosis.
- The tcpEStatsPathTable contains objects that can be used to
infer detailed behavior of the Internet path, such as the
extent that there are losses or segment reordering, etc.
- The tcpEStatsStackTable contains objects that are most
useful for determining how well the TCP control algorithms
are coping with this particular path.
- The tcpEStatsAppTable provides objects that are useful for
determining if the application using TCP is limiting TCP
performance.
- The tcpEStatsTuneTable provides per connection controls that can
be used to work around a number of common problems that
plague TCP over some paths.
- The two notifications defined in this MIB module are
tcpEStatsEstablishNotification, indicating that a new
connection has been accepted (or established see below), and
tcpEStatsCloseNotification, indicating that an existing
connection has recently closed.
- The tcpEStatsListenerTable is specifically designed to
provides information that is useful for diagnosing SYN-flood
Denial-of-Service attacks, where a server is overwhelmed by
forged or otherwise malicious connection attempts. There
are several different techniques that are used to defend
against SYN-flooding but none are standardized, and most
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have never been well described in the literature (ergo there
are no normative references). These different techniques
all have the same basic characteristics which are
instrumentable with a common set of objects even though the
techniques differ greatly in the details.
All SYN-flood defenses avoid allocating significant
resources (memory or CPU) to incoming (passive open)
connections until the connections meet some liveness
criteria (to defend against forged IP source addresses) and
the server has sufficient resources to process the incoming
request. Note that allocating resources is an
implementation specific event that may not correspond to a
observable protocol event (e.g. segments on the wire).
There are two general concepts that can be applied to all
known SYN-flood defenses. There is generally a well defined
event when a connection is allocated full resources, and a
"backlog" - a queue of embryonic connections that have been
allocated only partial resources.
In many implementations incoming TCP connections are allocated
resources as a side affect of the POSIX [POSIX] accept() call.
For this reason we use the terminology "accepting a connection"
to refer to this event: committing sufficient network resources
to process the incoming request. Accepting a connection
typically entails allocating memory for the protocol control
block [RFC793], the per connection table rows described in
this MIB and CPU resources, such as process table entries
or threads.
Note that it is not useful to accept connections before they
are ESTABLISHED, because this would create an easy opportunity
for Denial-of-Service attacks, using forged source IP
addresses.
The backlog consists of connections that are in SYN-RCVD or
ESTABLISHED states, that have not been accepted. For
purposes of this MIB we assume that these connections
have been allocated some resources (e.g. an embryonic
protocol control block) but not full resources (e.g. do not
yet have MIB table rows).
Note that some SYN-Flood defenses dispense with explicit
SYN-RCVD state by cryptographically encoding the state in
the ISS of the SYN-ACK, and then using the sequence number
of the first ACK to reconstruct the SYN-RCVD state before
transitioning to the ESTABLISHED state. For these
implementations there is no explicit representation of the
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SYN-RCVD state and the backlog only consists of connections
that are ESTABLISHED and are waiting to be ACCEPTED.
Furthermore, most SYN-flood defenses have some mechanism to
throttle connections that might otherwise overwhelm this
endpoint. They generally use some combination of discarding
incoming SYNs and discarding connections already in the
backlog. This does not cause all connections from
legitimate clients to fail, as long as the clients
retransmit the SYN or first ACK as specified in
RFC793. Most of the diversity in SYN flood defenses arises
in variations in these algorithms to limit load, and
therefore they can not conveniently be instrumented with a
common standard MIB.
The Listen Table instruments all passively opened TCP
connections in terms of observable protocol events
(e.g. sent and received segments) and resource allocation
events (entering the backlog and being accepted). This
approach eases generalization to SYN-flood mechanisms that
use alternate TCP state transition diagrams and implicit
mechanisms to encode some states.
4. TCP Extended Statistics MIB
TCP-ESTATS-MIB DEFINITIONS ::= BEGIN
IMPORTS
MODULE-IDENTITY, Counter32, Integer32, Unsigned32,
Gauge32, OBJECT-TYPE, experimental,
NOTIFICATION-TYPE
FROM SNMPv2-SMI
MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
FROM SNMPv2-CONF
ZeroBasedCounter32
FROM RMON2-MIB -- [RFC2021]
ZeroBasedCounter64
FROM HCNUM-TC -- [RFC2856]
TEXTUAL-CONVENTION,
DateAndTime, TruthValue, TimeStamp
FROM SNMPv2-TC
InetAddressType, InetAddress,
InetPortNumber
FROM INET-ADDRESS-MIB -- [RFC4001]
tcpListenerEntry
FROM TCP-MIB; -- [RFC4022]
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tcpEStatsMIB MODULE-IDENTITY
LAST-UPDATED "200510231248Z" -- Oct 23, 2005
ORGANIZATION "IETF TSV Working Group"
CONTACT-INFO
"Matt Mathis
John Heffner
Raghu Reddy
Web100 Project
Pittsburgh Supercomputing Center
4400 Fifth Ave
Pittsburgh, PA 15213
Email: mathis@psc.edu, jheffner@psc.edu, rreddy@psc.edu
Rajiv Raghunarayan
Cisco Systems Inc.
San Jose, CA 95134
Phone: 408 853 9612
Email: raraghun@cisco.com
Jon Saperia
JDS Consulting, Inc.
174 Chapman Street
Watertown, MA 02472
Phone: 617-744-1079
Email: saperia@jdscons.com "
DESCRIPTION
"Documentation of TCP Extended Performance Instrumentation
variables from the Web100 project. [Web100]
Copyright (C) The Internet Society (2005). This version
of this MIB module is a part of RFC xxxx; see the RFC
itself for full legal notices."
-- RFC Editor: replace xxxx with actual RFC number & remove note
REVISION "200510231248Z" -- Oct 23, 2005
DESCRIPTION
"Initial version, published as RFC xxxx."
-- RFC Editor assigns RFC xxxx
::= { experimental 9999 }
-- IANA assigns base OID xxxx
tcpEStatsNotifications OBJECT IDENTIFIER ::= { tcpEStatsMIB 0 }
tcpEStatsMIBObjects OBJECT IDENTIFIER ::= { tcpEStatsMIB 1 }
tcpEStatsConformance OBJECT IDENTIFIER ::= { tcpEStatsMIB 2 }
tcpEStats OBJECT IDENTIFIER ::= { tcpEStatsMIBObjects 1 }
tcpEStatsControl OBJECT IDENTIFIER ::= { tcpEStatsMIBObjects 2 }
tcpEStatsScalar OBJECT IDENTIFIER ::= { tcpEStatsMIBObjects 3 }
--
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-- Textual Conventions
--
TcpEStatsOperation ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"Indicates whether the table or notification controlled
by an object with this syntax is enabled or in a
disabled state."
SYNTAX INTEGER {
enabled(1),
disabled(2)
}
--
-- TCP Extended statistics scalars
--
tcpEStatsListenerTableLastChange OBJECT-TYPE
SYNTAX TimeStamp
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of sysUpTime at the time of the last
creation or deletion of an entry in the tcpListenerTable.
If the number of entries has been unchanged since the
last re-initialization of the local network management
subsystem, then this object contains a zero value."
::= { tcpEStatsScalar 3 }
-- ================================================================
--
-- The tcpEStatsControl Group
--
-- The scalar objects in this group are used to control the
-- activation and deactivation of the TCP Extended Statistics
-- tables and notifications in this module.
--
tcpEStatsControlPath OBJECT-TYPE
SYNTAX TcpEStatsOperation
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"Controls the activation of the TCP Path
Statistics table."
DEFVAL { disabled }
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::= { tcpEStatsControl 1 }
tcpEStatsControlStack OBJECT-TYPE
SYNTAX TcpEStatsOperation
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"Controls the activation of the TCP Stack
Statistics table."
DEFVAL { disabled }
::= { tcpEStatsControl 2 }
tcpEStatsControlApp OBJECT-TYPE
SYNTAX TcpEStatsOperation
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"Controls the activation of the TCP Application
Statistics table."
DEFVAL { disabled }
::= { tcpEStatsControl 3 }
tcpEStatsControlTune OBJECT-TYPE
SYNTAX TcpEStatsOperation
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"Controls the activation of the TCP Tuning
table."
DEFVAL { disabled }
::= { tcpEStatsControl 4 }
tcpEStatsControlNotify OBJECT-TYPE
SYNTAX TcpEStatsOperation
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"Controls the generation of all notifications defined in
this MIB."
DEFVAL { disabled }
::= { tcpEStatsControl 5 }
tcpEStatsConnTableLatency OBJECT-TYPE
SYNTAX Integer32 (0..30)
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Specifies the number of seconds that the entity will
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retain entries in the TCP connection tables, after the
connection first enters the closed state. The entity
SHOULD provide a configuration option to enable
customization of this value. A value of 0
results in entries being removed from the tables as soon as
the connection enters the closed state. The value of
this object pertains to the following tables:
tcpEStatsConnectIdTable
tcpEStatsPerfTable
tcpEStatsPathTable
tcpEStatsStackTable
tcpEStatsAppTable
tcpEStatsTuneTable"
::= { tcpEStatsControl 6 }
-- ================================================================
--
-- Listener Table
--
tcpEStatsListenerTable OBJECT-TYPE
SYNTAX SEQUENCE OF TcpEStatsListenerEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table contains information about TCP Listeners,
in addition to the information maintained by the
tcpListenerTable RFC4022."
::= { tcpEStats 10 }
tcpEStatsListenerEntry OBJECT-TYPE
SYNTAX TcpEStatsListenerEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"Each entry in the table contains information about
a specific TCP Listener."
AUGMENTS { tcpListenerEntry }
::= { tcpEStatsListenerTable 1 }
TcpEStatsListenerEntry ::= SEQUENCE {
tcpEStatsListenerStartTime TimeStamp,
tcpEStatsListenerSynRcvd ZeroBasedCounter32,
tcpEStatsListenerInitial ZeroBasedCounter32,
tcpEStatsListenerEstablished ZeroBasedCounter32,
tcpEStatsListenerAccepted ZeroBasedCounter32,
tcpEStatsListenerExceedBacklog ZeroBasedCounter32,
tcpEStatsListenerHCSynRcvd ZeroBasedCounter64,
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tcpEStatsListenerHCInitial ZeroBasedCounter64,
tcpEStatsListenerHCEstablished ZeroBasedCounter64,
tcpEStatsListenerHCAccepted ZeroBasedCounter64,
tcpEStatsListenerHCExceedBacklog ZeroBasedCounter64,
tcpEStatsListenerCurrConns Gauge32,
tcpEStatsListenerMaxBacklog Integer32,
tcpEStatsListenerCurBacklog Gauge32,
tcpEStatsListenerCurEstabBacklog Gauge32
}
tcpEStatsListenerStartTime OBJECT-TYPE
SYNTAX TimeStamp
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of sysUpTime at the time this listener was
established. If the current state was entered prior to
the last re-initialization of the local network management
subsystem, then this object contains a zero value."
::= { tcpEStatsListenerEntry 1 }
tcpEStatsListenerSynRcvd OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of SYNs which have been received for this
listener. The total number of failed connections for
all reasons can be estimated to be tcpEStatsListenerSynRcvd
minus tcpEStatsListenerAccepted and
tcpEStatsListenerCurBacklog."
::= { tcpEStatsListenerEntry 2 }
tcpEStatsListenerInitial OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of connections for which the Listener
has allocated initial state and placed the
connection in the backlog. The may happen in the
SYN-RCVD or ESTABLISHED states, depending on the
implementation."
::= { tcpEStatsListenerEntry 3 }
tcpEStatsListenerEstablished OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
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STATUS current
DESCRIPTION
"The number of connections which have been established to
this endpoint. E.g. The number of first ACKs which have
been received for this listener."
::= { tcpEStatsListenerEntry 4 }
tcpEStatsListenerAccepted OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of connections for which the Listener
has successfully issued an accept, removing the connection
from the backlog."
::= { tcpEStatsListenerEntry 5 }
tcpEStatsListenerExceedBacklog OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of connections dropped from the
backlog by this listener due to all reasons. This
includes all connections that are allocated initial
resources but are not accepted for some reason."
::= { tcpEStatsListenerEntry 6 }
tcpEStatsListenerHCSynRcvd OBJECT-TYPE
SYNTAX ZeroBasedCounter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of SYNs which have been received for this
listener on systems that can process (or reject) more
than 1 million connections per second. See
tcpEStatsListenerSynRcvd."
::= { tcpEStatsListenerEntry 7 }
tcpEStatsListenerHCInitial OBJECT-TYPE
SYNTAX ZeroBasedCounter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of connections for which the Listener
has allocated initial state and placed the connection
in the backlog on systems that can process (or reject)
more than 1 million connections per second. See
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tcpEStatsListenerInitial."
::= { tcpEStatsListenerEntry 8 }
tcpEStatsListenerHCEstablished OBJECT-TYPE
SYNTAX ZeroBasedCounter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of connections which have been established to
this endpoint on systems that can process (or reject) more
than 1 million connections per second. See
tcpEStatsListenerEstablished."
::= { tcpEStatsListenerEntry 9 }
tcpEStatsListenerHCAccepted OBJECT-TYPE
SYNTAX ZeroBasedCounter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of connections for which the Listener
has successfully issued an accept, removing the connection
from the backlog on systems that can process (or reject)
more than 1 million connections per second. See
tcpEStatsListenerAccepted."
::= { tcpEStatsListenerEntry 10 }
tcpEStatsListenerHCExceedBacklog OBJECT-TYPE
SYNTAX ZeroBasedCounter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of connections dropped from the
backlog by this listener due to all reasons on
systems that can process (or reject) more than
1 million connections per second. See
tcpEStatsListenerHCExceedBacklog."
::= { tcpEStatsListenerEntry 11 }
tcpEStatsListenerCurrConns OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current number of connections in the ESTABLISHED
state, which have also been accepted. It excludes
connections that have been established but not accepted
because they are still subject to being discarded to
shed load without explicit action by either endpoint."
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::= { tcpEStatsListenerEntry 12 }
tcpEStatsListenerMaxBacklog OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum number of connections allowed in
backlog at one time."
::= { tcpEStatsListenerEntry 13 }
tcpEStatsListenerCurBacklog OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current number of connections that are in backlog.
This counter MUST include connections in ESTABLISHED state,
for which the Listener has not yet issued an accept,
and MAY include connections in SYN-RECEIVED state."
::= { tcpEStatsListenerEntry 14 }
tcpEStatsListenerCurEstabBacklog OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current number of connections in backlog that are
in the ESTABLISHED state, but for which the Listener has
not yet issued an accept."
::= { tcpEStatsListenerEntry 15 }
-- ================================================================
--
-- TCP Connection ID Table
--
-- There is overlap with the RFC 4022 [RFC4022] TCP Connection table
-- because there is a semantic difference in the latency of row
-- removal in this table. Rows are expected to remain in this
-- table longer than in a standard TCP Connection table. Other
-- than this latency difference, the semantics of the first six
-- objects in this table are the same as the TCP Connection
-- table and the DESCRIPTIONS come from RFC 4022.
tcpEStatsConnectIdTable OBJECT-TYPE
SYNTAX SEQUENCE OF TcpEStatsConnectIdEntry
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MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table maps a connection ID used by other tables in
this MIB Module with the information that uniquely
identifies each active TCP connection. Entries are
retained in this table for the number of seconds
indicated by the tcpEStatsConnTableLatency object, after
the TCP connection first enters the closed state."
::= { tcpEStats 1 }
tcpEStatsConnectIdEntry OBJECT-TYPE
SYNTAX TcpEStatsConnectIdEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"Each entry in this table maps a TCP connection
4-tuple to a connection index."
INDEX { tcpEStatsConnectLocalAddressType,
tcpEStatsConnectLocalAddress,
tcpEStatsConnectLocalPort,
tcpEStatsConnectRemAddressType,
tcpEStatsConnectRemAddress,
tcpEStatsConnectRemPort }
::= { tcpEStatsConnectIdTable 1 }
TcpEStatsConnectIdEntry ::= SEQUENCE {
tcpEStatsConnectLocalAddressType InetAddressType,
tcpEStatsConnectLocalAddress InetAddress,
tcpEStatsConnectLocalPort InetPortNumber,
tcpEStatsConnectRemAddressType InetAddressType,
tcpEStatsConnectRemAddress InetAddress,
tcpEStatsConnectRemPort InetPortNumber,
tcpEStatsConnectIndex Unsigned32
}
tcpEStatsConnectLocalAddressType OBJECT-TYPE
SYNTAX InetAddressType
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The address type of tcpEStatsConnectLocalAddress."
::= { tcpEStatsConnectIdEntry 1 }
tcpEStatsConnectLocalAddress OBJECT-TYPE
SYNTAX InetAddress
MAX-ACCESS not-accessible
STATUS current
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DESCRIPTION
"The local IP address for this TCP connection. The type
of this address is determined by the value of
tcpEStatsConnectLocalAddressType.
As this object is used in the index for the
tcpEStatsConnectIdTable, implementors of this table should
be careful not to create entries that would result in OIDs
with more than 128 sub-identifiers; else the information
cannot be accessed using SNMPv1, SNMPv2c or SNMPv3."
::= { tcpEStatsConnectIdEntry 2 }
tcpEStatsConnectLocalPort OBJECT-TYPE
SYNTAX InetPortNumber
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The local port number for this TCP connection."
::= {tcpEStatsConnectIdEntry 3 }
tcpEStatsConnectRemAddressType OBJECT-TYPE
SYNTAX InetAddressType
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The address type of tcpEStatsConnectRemAddress."
::= { tcpEStatsConnectIdEntry 4 }
tcpEStatsConnectRemAddress OBJECT-TYPE
SYNTAX InetAddress
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The remote IP address for this TCP connection. The type
of this address is determined by the value of
tcpEStatsConnectRemAddressType.
As this object is used in the index for the
tcpEStatsConnectIdTable, implementors of this table should
be careful not to create entries that would result in OIDs
with more than 128 sub-identifiers; else the information
cannot be accessed using SNMPv1, SNMPv2c or SNMPv3."
::= { tcpEStatsConnectIdEntry 5 }
tcpEStatsConnectRemPort OBJECT-TYPE
SYNTAX InetPortNumber
MAX-ACCESS not-accessible
STATUS current
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DESCRIPTION
"The remote port number for this TCP connection."
::= { tcpEStatsConnectIdEntry 6 }
tcpEStatsConnectIndex OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"A unique integer value assigned to each TCP Connection
entry. Assignment will begin at 1 and increase to the
maximum value and then start again at 1 skipping in use
values."
::= { tcpEStatsConnectIdEntry 7 }
-- ================================================================
--
-- Basic TCP Performance Statistics
--
tcpEStatsPerfTable OBJECT-TYPE
SYNTAX SEQUENCE OF TcpEStatsPerfEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table contains objects that are useful for
measuring TCP performance and first line problem
diagnosis. Most objects in this table directly
expose some TCP state variable or are easily
implemented as simple functions (e.g. Maximum)
of TCP state variables."
::= { tcpEStats 2 }
tcpEStatsPerfEntry OBJECT-TYPE
SYNTAX TcpEStatsPerfEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"Each entry in this table has information about the
characteristics of each active and recently closed tcp
connection."
INDEX { tcpEStatsConnectIndex }
::= { tcpEStatsPerfTable 1 }
TcpEStatsPerfEntry ::= SEQUENCE {
tcpEStatsPerfSegsOut ZeroBasedCounter32,
tcpEStatsPerfDataSegsOut ZeroBasedCounter32,
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tcpEStatsPerfDataOctetsOut ZeroBasedCounter32,
tcpEStatsPerfHCDataOctetsOut ZeroBasedCounter64,
tcpEStatsPerfSegsRetrans ZeroBasedCounter32,
tcpEStatsPerfOctetsRetrans ZeroBasedCounter32,
tcpEStatsPerfSegsIn ZeroBasedCounter32,
tcpEStatsPerfDataSegsIn ZeroBasedCounter32,
tcpEStatsPerfDataOctetsIn ZeroBasedCounter32,
tcpEStatsPerfHCDataOctetsIn ZeroBasedCounter64,
tcpEStatsPerfElapsedSecs ZeroBasedCounter32,
tcpEStatsPerfElapsedMicroSecs ZeroBasedCounter32,
tcpEStatsPerfStartTimeStamp DateAndTime,
tcpEStatsPerfCurMSS Gauge32,
tcpEStatsPerfPipeSize Gauge32,
tcpEStatsPerfMaxPipeSize Gauge32,
tcpEStatsPerfSmoothedRTT Gauge32,
tcpEStatsPerfCurRTO Gauge32,
tcpEStatsPerfCongSignals ZeroBasedCounter32,
tcpEStatsPerfCurCwnd Gauge32,
tcpEStatsPerfCurSsthresh Gauge32,
tcpEStatsPerfTimeouts ZeroBasedCounter32,
tcpEStatsPerfCurRwinSent Gauge32,
tcpEStatsPerfMaxRwinSent Gauge32,
tcpEStatsPerfZeroRwinSent Gauge32,
tcpEStatsPerfCurRwinRcvd Gauge32,
tcpEStatsPerfMaxRwinRcvd Gauge32,
tcpEStatsPerfZeroRwinRcvd Gauge32,
tcpEStatsPerfSndLimTransRwin ZeroBasedCounter32,
tcpEStatsPerfSndLimTransCwnd ZeroBasedCounter32,
tcpEStatsPerfSndLimTransSnd ZeroBasedCounter32,
tcpEStatsPerfSndLimTimeRwin ZeroBasedCounter32,
tcpEStatsPerfSndLimTimeCwnd ZeroBasedCounter32,
tcpEStatsPerfSndLimTimeSnd ZeroBasedCounter32
}
--
-- The following objects provide statistics on aggregate
-- segments and data sent on a connection. These provide a
-- direct measure of the Internet capacity consumed by a
-- connection.
--
tcpEStatsPerfSegsOut OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of segments sent."
::= { tcpEStatsPerfEntry 1 }
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tcpEStatsPerfDataSegsOut OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of segments sent containing a positive length
data segment."
::= { tcpEStatsPerfEntry 2 }
tcpEStatsPerfDataOctetsOut OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of octets of data contained in transmitted
segments, including retransmitted data. Note that this does
not include TCP headers."
::= { tcpEStatsPerfEntry 3 }
tcpEStatsPerfHCDataOctetsOut OBJECT-TYPE
SYNTAX ZeroBasedCounter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of octets of data contained in transmitted
segments, including retransmitted data, on systems that can
transmit more than 10 million bits per second. Note that
this does not include TCP headers."
::= { tcpEStatsPerfEntry 4 }
tcpEStatsPerfSegsRetrans OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of segments transmitted containing at least some
retransmitted data."
::= { tcpEStatsPerfEntry 5 }
tcpEStatsPerfOctetsRetrans OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of octets retransmitted."
::= { tcpEStatsPerfEntry 6 }
tcpEStatsPerfSegsIn OBJECT-TYPE
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SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of segments received."
::= { tcpEStatsPerfEntry 7 }
tcpEStatsPerfDataSegsIn OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of segments received containing a positive
length data segment."
::= { tcpEStatsPerfEntry 8 }
tcpEStatsPerfDataOctetsIn OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of octets contained in received data segments,
including retransmitted data. Note that this does not
include TCP headers."
::= { tcpEStatsPerfEntry 9 }
tcpEStatsPerfHCDataOctetsIn OBJECT-TYPE
SYNTAX ZeroBasedCounter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of octets contained in received data segments,
including retransmitted data, on systems that can receive
more than 10 million bits per second. Note that this does
not include TCP headers."
::= { tcpEStatsPerfEntry 10 }
tcpEStatsPerfElapsedSecs OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The seconds part of the time elapsed between
tcpEStatsPerfStartTimeStamp and the most recent protocol
event (segment sent or received)."
::= { tcpEStatsPerfEntry 11 }
tcpEStatsPerfElapsedMicroSecs OBJECT-TYPE
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SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The micro-second part of time elapsed between
tcpEStatsPerfStartTimeStamp to the most recent protocol
event (segment sent or received). This may be updated in
what ever time granularity is the system supports."
::= { tcpEStatsPerfEntry 12 }
tcpEStatsPerfStartTimeStamp OBJECT-TYPE
SYNTAX DateAndTime
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Time at which this row was created and all
ZeroBasedCounters in the row were initialized to zero."
::= { tcpEStatsPerfEntry 13 }
--
-- The following objects can be used to fit minimal
-- performance models to the TCP data rate.
--
tcpEStatsPerfCurMSS OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current maximum segment size (MSS), in octets."
::= { tcpEStatsPerfEntry 14 }
tcpEStatsPerfPipeSize OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The TCP senders current estimate of the number of
unacknowledged data octets in the network.
While not in recovery, this is the same as ``Flight Size''
as defined in RFC2581.
While in recovery, this is the same as ``pipe'' as defined
in RFC3517.
If RFC3517 is not in effect, the data octets in flight can
be estimated as SND.NXT minus SND.UNA plus any
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retransmitted data, minus some measure of the data that has
left the network. For example, with Reno or NewReno style
TCP, the number of duplicate acknowledgement is used to
count the number of segments that have left the network.
I.e.: PipeSize=SND.NXT-SND.UNA+(retransmits-dupacks)*CurMSS"
::= { tcpEStatsPerfEntry 15 }
tcpEStatsPerfMaxPipeSize OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum value of tcpEStatsPerfPipeSize, for this
connection."
::= { tcpEStatsPerfEntry 16 }
tcpEStatsPerfSmoothedRTT OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The smoothed round trip time, in milliseconds, used in
calculation of the RTO. See SRTT in [RFC2988]."
::= { tcpEStatsPerfEntry 17 }
tcpEStatsPerfCurRTO OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current value of the retransmit timer RTO, in
milliseconds. See [RFC2988]."
::= { tcpEStatsPerfEntry 18 }
tcpEStatsPerfCongSignals OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of multiplicative downward congestion window
adjustments due to all forms of congestion signals,
including Fast Retransmit, ECN and timeouts. This object
summarizes all events that invoke the MD portion of AIMD
congestion control, and as such is the best indicator of
how cwnd is being affected by congestion.
Note that retransmission timeouts multiplicatively reduce
the window implicitly by setting ssthresh, and should be
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included in tcpEStatsPerfCongSignals. In order to minimize
spurious congestion indications due to out-of-order
segments, tcpEStatsPerfCongSignals should be incremented in
association with the Fast Retransmit algorithm."
::= { tcpEStatsPerfEntry 19 }
tcpEStatsPerfCurCwnd OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current congestion window, in octets. See [RFC2581]."
::= { tcpEStatsPerfEntry 20 }
tcpEStatsPerfCurSsthresh OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current slow start threshold in octets. See [RFC2581]."
::= { tcpEStatsPerfEntry 21 }
tcpEStatsPerfTimeouts OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of times the retransmit timeout has expired when
the RTO backoff multiplier is equal to one. See [RFC2988]."
::= { tcpEStatsPerfEntry 22 }
--
-- The following objects instrument our receiver window
-- updates to the remote sender. These can be used to
-- determine if the local receiver is exerting flow control
-- back pressure on the remote sender.
--
tcpEStatsPerfCurRwinSent OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The most recent window advertisement sent, in octets."
::= { tcpEStatsPerfEntry 23 }
tcpEStatsPerfMaxRwinSent OBJECT-TYPE
SYNTAX Gauge32
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MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum window advertisement sent, in octets."
::= { tcpEStatsPerfEntry 24 }
tcpEStatsPerfZeroRwinSent OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of acknowledgments sent announcing a zero
receive window, when the previously announced window was
not zero."
::= { tcpEStatsPerfEntry 25 }
--
-- The following objects instrument receiver window updates
-- from the far end-system to determine if the remote receiver
-- has sufficient buffer space or is exerting flow-control
-- back pressure on the local sender.
--
tcpEStatsPerfCurRwinRcvd OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The most recent window advertisement received, in octets."
::= { tcpEStatsPerfEntry 26 }
tcpEStatsPerfMaxRwinRcvd OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum window advertisement received, in octets."
::= { tcpEStatsPerfEntry 27 }
tcpEStatsPerfZeroRwinRcvd OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of acknowledgments received announcing a zero
receive window, when the previously announced window was
not zero."
::= { tcpEStatsPerfEntry 28 }
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--
-- The following optional objects can be used to quickly
-- identify which subsystems are limiting TCP performance.
-- There are three parallel pairs of instruments that measure
-- the extent to which TCP performance is limited by the
-- announced receiver window (indicating a receiver
-- bottleneck), the current congestion window or
-- retransmission timeout (indicating a path bottleneck) and
-- all others events (indicating a sender bottleneck).
--
-- These instruments should be updated every time the TCP
-- output routine stops sending data. The elapsed time since
-- the previous stop is accumulated into the appropriate
-- object as determined by the previous stop reason (e.g. stop
-- state). The current stop reason determines which timer will
-- be updated the next time TCP output stops.
--
-- Since there is no explicit stop at the beginning of a
-- timeout, it is necessary to retroactively reclassify the
-- previous stop as 'Congestion Limited'.
--
tcpEStatsPerfSndLimTransRwin OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of transitions into the 'Receiver Limited' state
from either the 'Congestion Limited' or 'Sender Limited'
states. This state is entered whenever TCP transmission
stops because the sender has filled the announced receiver
window."
::= { tcpEStatsPerfEntry 31 }
tcpEStatsPerfSndLimTransCwnd OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of transitions into the 'Congestion Limited'
state from either the 'Receiver Limited' or 'Sender
Limited' states. This state is entered whenever TCP
transmission stops because the sender has reached some
limit defined by congestion control (e.g. cwnd) or other
algorithms (retransmission timeouts) designed to control
network traffic."
::= { tcpEStatsPerfEntry 32 }
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tcpEStatsPerfSndLimTransSnd OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of transitions into the 'Sender Limited' state
from either the 'Receiver Limited' or 'Congestion Limited'
states. This state is entered whenever TCP transmission
stops due to some sender limit such as running out of
application data or other resources and the Karn algorithm.
When TCP stops sending data for any reason which can not be
classified as Receiver Limited or Congestion Limited it
must be treated as Sender Limited."
::= { tcpEStatsPerfEntry 33 }
tcpEStatsPerfSndLimTimeRwin OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The cumulative time (in milliseconds) spent in the
'Receiver Limited' state. See tcpEStatsPerfSndLimTransRwin."
::= { tcpEStatsPerfEntry 34 }
tcpEStatsPerfSndLimTimeCwnd OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The cumulative time (in milliseconds) spent in the
'Congestion Limited' state. See
tcpEStatsPerfSndLimTransCwnd. When there is a
retransmission timeout, it should be counted in
tcpEStatsPerfSndLimTimeCwnd (and not the cumulative time
for some other state.)"
::= { tcpEStatsPerfEntry 35 }
tcpEStatsPerfSndLimTimeSnd OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The cumulative time (in milliseconds) spent in the 'Sender
Limited' state. See tcpEStatsPerfSndLimTransSnd."
::= { tcpEStatsPerfEntry 36 }
-- ================================================================
--
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-- Statistics for diagnosing path problems
--
tcpEStatsPathTable OBJECT-TYPE
SYNTAX SEQUENCE OF TcpEStatsPathEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table contains objects that can be used to infer
detailed behavior of the Internet path, such as the
extent that there is reordering, ECN bits and if
RTT fluctuations are correlated to losses."
::= { tcpEStats 3 }
tcpEStatsPathEntry OBJECT-TYPE
SYNTAX TcpEStatsPathEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"Each entry in this table has information about the
characteristics of each active and recently closed tcp
connection."
INDEX { tcpEStatsConnectIndex }
::= { tcpEStatsPathTable 1 }
TcpEStatsPathEntry ::= SEQUENCE {
tcpEStatsPathRetranThresh Gauge32,
tcpEStatsPathNonRecovDAEpisodes Integer32,
tcpEStatsPathSumOctetsReordered Integer32,
tcpEStatsPathNonRecovDA ZeroBasedCounter32,
tcpEStatsPathSampleRTT Gauge32,
tcpEStatsPathRTTVar Gauge32,
tcpEStatsPathMaxRTT Gauge32,
tcpEStatsPathMinRTT Gauge32,
tcpEStatsPathSumRTT ZeroBasedCounter32,
tcpEStatsPathHCSumRTT ZeroBasedCounter64,
tcpEStatsPathCountRTT ZeroBasedCounter32,
tcpEStatsPathMaxRTO Gauge32,
tcpEStatsPathMinRTO Gauge32,
tcpEStatsPathIpTtl Integer32,
tcpEStatsPathIpTosIn Integer32,
tcpEStatsPathIpTosOut Integer32,
tcpEStatsPathPreCongSumCwnd ZeroBasedCounter32,
tcpEStatsPathPreCongSumRTT ZeroBasedCounter32,
tcpEStatsPathPostCongSumRTT ZeroBasedCounter32,
tcpEStatsPathPostCongCountRTT ZeroBasedCounter32,
tcpEStatsPathECNsignals ZeroBasedCounter32,
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tcpEStatsPathECERcvd ZeroBasedCounter32,
tcpEStatsPathQuenchRcvd ZeroBasedCounter32,
tcpEStatsPathDupAckEpisodes ZeroBasedCounter32,
tcpEStatsPathDupAcksOut ZeroBasedCounter32,
tcpEStatsPathCERcvd ZeroBasedCounter32,
tcpEStatsPathECNSent ZeroBasedCounter32,
tcpEStatsPathECNNonceRcvd ZeroBasedCounter32
}
--
-- The following optional objects can be used to infer segment
-- reordering on the path from the local sender to the remote
-- receiver.
--
tcpEStatsPathRetranThresh OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of duplicate acknowledgments required to trigger
Fast Retransmit. Note that although this is constant in
traditional Reno TCP implementations, it is adaptive in
many newer TCPs."
::= { tcpEStatsPathEntry 1 }
tcpEStatsPathNonRecovDAEpisodes OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of duplicate acknowledgment episodes that did
not trigger a Fast Retransmit because ACK advanced prior to
the number of duplicate acknowledgments reaching
RetranThresh. See [RFC2581].
In many implementations this is the number of times the
'dupacks' counter is set to zero when it is non-zero but
less than RetranThresh.
Note that tcpEStatsPathNonRecovDAEpisodes divided by
tcpEStatsPerfDataSegsOut is an estimate of the frequency of
data reordering on the forward path."
::= { tcpEStatsPathEntry 2 }
tcpEStatsPathSumOctetsReordered OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-only
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STATUS current
DESCRIPTION
"The sum of the amounts SND.UNA advances on the
acknowledgment which ends a dup-ack episode without a
retransmission.
Note tcpEStatsPathSumOctetsReordered divided by
tcpEStatsPathNonRecovDAEpisodes is an estimates of the
average reordering distance, in octets."
::= { tcpEStatsPathEntry 3 }
tcpEStatsPathNonRecovDA OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Duplicate acks (or SACKS) that did not trigger a Fast
Retransmit because ACK advanced prior to the number of
duplicate acknowledgments reaching RetranThresh.
In many implementations, this is the sum of the 'dupacks'
counter, just before it is set to zero because ACK advanced
without a Fast Retransmit.
Note that tcpEStatsPathNonRecovDA divided by
tcpEStatsPathNonRecovDAEpisodes is an estimate of the
average reordering distance in segments."
::= { tcpEStatsPathEntry 4 }
--
-- The following optional objects instrument the round trip
-- time estimator and the retransmission timeout timer. See
-- [RFC2988].
--
tcpEStatsPathSampleRTT OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The most recent raw round trip time measurement, in
milliseconds, used in calculation of the RTO."
::= { tcpEStatsPathEntry 21 }
tcpEStatsPathRTTVar OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
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DESCRIPTION
"The round trip time variation, in milliseconds, used in
calculation of the RTO. See RTTVAR in [RFC2988]."
::= { tcpEStatsPathEntry 22 }
tcpEStatsPathMaxRTT OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum sampled round trip time, in milliseconds."
::= { tcpEStatsPathEntry 23 }
tcpEStatsPathMinRTT OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The minimum sampled round trip time, in milliseconds."
::= { tcpEStatsPathEntry 24 }
tcpEStatsPathSumRTT OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The sum of all sampled round trip times, in milliseconds.
Note that the change in tcpEStatsPathSumRTT divided by the
change in tcpEStatsPathCountRTT is the mean RTT, uniformly
averaged over an enter interval."
::= { tcpEStatsPathEntry 25 }
tcpEStatsPathHCSumRTT OBJECT-TYPE
SYNTAX ZeroBasedCounter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The sum of all sampled round trip times, in milliseconds,
on all systems that implement multiple concurrent RTT
measurements.
Note that the change in tcpEStatsPathHCSumRTT divided by
the change in tcpEStatsPathCountRTT is the mean RTT,
uniformly averaged over an enter interval."
::= { tcpEStatsPathEntry 26 }
tcpEStatsPathCountRTT OBJECT-TYPE
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SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of round trip time samples included in
tcpEStatsPathSumRTT."
::= { tcpEStatsPathEntry 27 }
tcpEStatsPathMaxRTO OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum value of the retransmit timer RTO, in
milliseconds. See [RFC2988]."
::= { tcpEStatsPathEntry 28 }
tcpEStatsPathMinRTO OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The minimum value of the retransmit timer RTO, in
milliseconds. See [RFC2988]."
::= { tcpEStatsPathEntry 29 }
--
-- The following optional objects provide information about
-- how TCP is using the IP layer.
--
tcpEStatsPathIpTtl OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of the TTL field carried in the most recently
received IP header. This is sometimes useful to detect
changing or unstable routes."
::= { tcpEStatsPathEntry 30 }
tcpEStatsPathIpTosIn OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of the IPv4 Type Of Service octet, or the IPv6
traffic class octet, carried in the most recently received
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IP header. See [RFC2474] and [RFC3260].
This is useful to diagnose interactions between TCP and any
IP layer packet scheduling and delivery policy, which might
be in effect to implement QoS."
::= { tcpEStatsPathEntry 31 }
tcpEStatsPathIpTosOut OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of the IPv4 Type Of Service octet, or the IPv6
traffic class octet, carried in the most recently
transmitted IP header. See [RFC2474] and [RFC3260].
This is useful to diagnose interactions between TCP and any
IP layer packet scheduling and delivery policy, which might
be in effect to implement QoS."
::= { tcpEStatsPathEntry 32 }
--
-- The following optional objects characterize the congestion
-- feedback signals by collecting statistics on how the
-- congestion events are correlated to losses, changes in RTT
-- and other protocol events.
--
tcpEStatsPathPreCongSumCwnd OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The sum of the values of the congestion window, in octets,
captured each time a congestion signal is received. This
MUST be updated each time tcpEStatsPerfCongSignals is
incremented, such that the ratio is the average window at
congestion."
::= { tcpEStatsPathEntry 33 }
tcpEStatsPathPreCongSumRTT OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Sum of the last sample of the RTT (tcpEStatsPathSampleRTT)
prior to received congestion signals. This MUST be updated
each time tcpEStatsPerfCongSignals is incremented, such
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that the ratio is the average RTT just prior to congestion."
::= { tcpEStatsPathEntry 34 }
tcpEStatsPathPostCongSumRTT OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Sum of the first RTT sample following a received congestion
signal."
::= { tcpEStatsPathEntry 35 }
tcpEStatsPathPostCongCountRTT OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of RTT samples included in
tcpEStatsPathPostCongSumRTT such that the ratio is average
RTT just after congestion."
::= { tcpEStatsPathEntry 36 }
--
-- The following optional objects can be used to detect other
-- types of non-loss congestion signals such as source quench
-- or ECN.
--
tcpEStatsPathECNsignals OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of congestion signals delivered via all forms of
explicit congestion notification including the ECE bit and
failing the ECN nonce check, etc."
::= { tcpEStatsPathEntry 37 }
tcpEStatsPathECERcvd OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of congestion signals received via the ECE bit
[RFC3168]."
::= { tcpEStatsPathEntry 38 }
tcpEStatsPathQuenchRcvd OBJECT-TYPE
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SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of ICMP quench messages that are treated as
congestion signals."
::= { tcpEStatsPathEntry 39 }
--
-- The following optional objects are receiver side
-- instruments of the path from the sender to the receiver. In
-- general the receiver has less information about the state
-- of the path, because the receiver does not have a robust
-- mechanism to infer the sender's actions.
--
tcpEStatsPathDupAckEpisodes OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of Duplicate Acks Sent when prior Ack was not
duplicate. This is the number of times that a contiguous
series of duplicate acknowledgments have been sent.
This is an indication of the number of data segments lost
or reordered on the path from the remote TCP endpoint to
the near TCP endpoint."
::= { tcpEStatsPathEntry 40 }
tcpEStatsPathDupAcksOut OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of duplicate ACKs sent. The ratio of
tcpEStatsPathDupAcksOut to tcpEStatsPathDupAckEpisodes is
an indication of reorder or recovery distance."
::= { tcpEStatsPathEntry 41 }
tcpEStatsPathCERcvd OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Received segments with Congestion Experienced bits. See
[RFC3168]."
::= { tcpEStatsPathEntry 42 }
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tcpEStatsPathECNSent OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Number of times CE bits have set ECN. See [RFC3168]."
::= { tcpEStatsPathEntry 43 }
tcpEStatsPathECNNonceRcvd OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Number of ECN Nonces received. Note that the low bit is the
same as the one bit nonce sum."
::= { tcpEStatsPathEntry 44 }
-- ================================================================
--
-- Statistics for diagnosing stack algorithms
--
tcpEStatsStackTable OBJECT-TYPE
SYNTAX SEQUENCE OF TcpEStatsStackEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table contains objects that are most useful for
determining how well some of the TCP control
algorithms are coping with this particular
path."
::= { tcpEStats 4 }
tcpEStatsStackEntry OBJECT-TYPE
SYNTAX TcpEStatsStackEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"Each entry in this table has information about the
characteristics of each active and recently closed tcp
connection."
INDEX { tcpEStatsConnectIndex }
::= { tcpEStatsStackTable 1 }
TcpEStatsStackEntry ::= SEQUENCE {
tcpEStatsStackState INTEGER,
tcpEStatsStackSACK TruthValue,
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tcpEStatsStackTimeStamps TruthValue,
tcpEStatsStackECN TruthValue,
tcpEStatsStackNagle TruthValue,
tcpEStatsStackSndWindScale Integer32,
tcpEStatsStackRcvWindScale Integer32,
tcpEStatsStackActiveOpen TruthValue,
tcpEStatsStackMaxSsCwnd Gauge32,
tcpEStatsStackMaxCaCwnd Gauge32,
tcpEStatsStackMaxSsthresh Gauge32,
tcpEStatsStackMinSsthresh Gauge32,
tcpEStatsStackInRecovery INTEGER,
tcpEStatsStackDupAcksIn ZeroBasedCounter32,
tcpEStatsStackSpuriousFrDetected ZeroBasedCounter32,
tcpEStatsStackSpuriousRtoDetected ZeroBasedCounter32,
tcpEStatsStackMSSSent Unsigned32,
tcpEStatsStackMSSRcvd Unsigned32,
tcpEStatsStackWinScaleSent Integer32,
tcpEStatsStackWinScaleRcvd Integer32,
tcpEStatsStackSACKokSent TruthValue,
tcpEStatsStackSACKokRcvd TruthValue,
tcpEStatsStackTimeStampSent TruthValue,
tcpEStatsStackTimeStampRcvd TruthValue,
tcpEStatsStackSoftErrors ZeroBasedCounter32,
tcpEStatsStackSoftErrorReason INTEGER,
tcpEStatsStackSndInitial Counter32,
tcpEStatsStackRecInitial Counter32,
tcpEStatsStackSlowStart ZeroBasedCounter32,
tcpEStatsStackCongAvoid ZeroBasedCounter32,
tcpEStatsStackOtherReductions ZeroBasedCounter32,
tcpEStatsStackCongOverCount ZeroBasedCounter32,
tcpEStatsStackFastRetran ZeroBasedCounter32,
tcpEStatsStackSubsequentTimeouts ZeroBasedCounter32,
tcpEStatsStackCurTimeoutCount Gauge32,
tcpEStatsStackAbruptTimeouts ZeroBasedCounter32,
tcpEStatsStackSACKsRcvd ZeroBasedCounter32,
tcpEStatsStackSACKBlocksRcvd ZeroBasedCounter32,
tcpEStatsStackSendStall ZeroBasedCounter32,
tcpEStatsStackDSACKDups ZeroBasedCounter32,
tcpEStatsStackMaxMSS Gauge32,
tcpEStatsStackMinMSS Gauge32,
tcpEStatsStackCurRetxQueue Gauge32,
tcpEStatsStackMaxRetxQueue Gauge32,
tcpEStatsStackCurReasmQueue Gauge32,
tcpEStatsStackMaxReasmQueue Gauge32
}
--
-- The following objects indicate TCP state and if various
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-- optional TCP features or algorithms are enabled.
--
tcpEStatsStackState OBJECT-TYPE
SYNTAX INTEGER {
tcpESStateClosed(1),
tcpESStateListen(2),
tcpESStateSynSent(3),
tcpESStateSynReceived(4),
tcpESStateEstablished(5),
tcpESStateFinWait1(6),
tcpESStateFinWait2(7),
tcpESStateCloseWait(8),
tcpESStateLastAck(9),
tcpESStateClosing(10),
tcpESStateTimeWait(11),
tcpESStateDeleteTcb(12)
}
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"An integer value representing the connection state from the
TCP State Transition Diagram. See [RFC793].
The value listen(2) is included only for parallelism to the
old tcpConnTable, and should not be used because the listen
state in managed by the tcpListenerTable.
The value DeleteTcb(12) is included only for parallelism to
the tcpConnTable mechanism for terminating connections,
although this table does not permit writing."
::= { tcpEStatsStackEntry 1 }
tcpEStatsStackSACK OBJECT-TYPE
SYNTAX TruthValue
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"True(1) if SACK has been negotiated on, else false(2). See
[RFC2018]."
::= { tcpEStatsStackEntry 2 }
tcpEStatsStackTimeStamps OBJECT-TYPE
SYNTAX TruthValue
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"True(1) if timestamps have been negotiated on, else
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false(2). See [RFC1323]."
::= { tcpEStatsStackEntry 3 }
tcpEStatsStackECN OBJECT-TYPE
SYNTAX TruthValue
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"True(1) if ECN has been negotiated on, else false(2). See
[RFC3168]."
::= { tcpEStatsStackEntry 4 }
tcpEStatsStackNagle OBJECT-TYPE
SYNTAX TruthValue
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"True(1) if the Nagle algorithm is being used, else
false(2). See [RFC896] and [RFC1122]."
::= { tcpEStatsStackEntry 5 }
tcpEStatsStackSndWindScale OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of Snd.Wind.Scale from [RFC1323]. Note that
tcpEStatsStackSndWindScale is either zero or the same as
tcpEStatsStackWinScaleRcvd."
::= { tcpEStatsStackEntry 6 }
tcpEStatsStackRcvWindScale OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of Rcv.Wind.Scale from [RFC1323]. Note that
tcpEStatsStackRcvWindScale is either zero or the same as
tcpEStatsStackWinScaleSent."
::= { tcpEStatsStackEntry 7 }
tcpEStatsStackActiveOpen OBJECT-TYPE
SYNTAX TruthValue
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"True(1) if the local connection traversed the SYN-SENT
state, else false(2). See [RFC793]."
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::= { tcpEStatsStackEntry 8 }
--
-- The following objects instrument the overall operation of
-- TCP congestion control and data retransmissions. These
-- instruments are sufficient to fit the actual performance to
-- an updated macroscopic performance model [RFC2581] [Mat97]
-- [Pad98].
--
tcpEStatsStackMaxSsCwnd OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum congestion window used during Slow Start, in
octets."
::= { tcpEStatsStackEntry 9 }
tcpEStatsStackMaxCaCwnd OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum congestion window used during Congestion
Avoidance, in octets."
::= { tcpEStatsStackEntry 10 }
tcpEStatsStackMaxSsthresh OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum slow start threshold, excluding the initial
value."
::= { tcpEStatsStackEntry 11 }
tcpEStatsStackMinSsthresh OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The minimum slow start threshold."
::= { tcpEStatsStackEntry 12 }
tcpEStatsStackInRecovery OBJECT-TYPE
SYNTAX INTEGER {
tcpESDataContiguous(1),
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tcpESDataUnordered(2),
tcpESDataRecovery(3)
}
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"An integer value representing the state of the loss
recovery for this connection.
tcpESDataContiguous(1) indicates that the remote receiver
is reporting contiguous data (no duplicate acknowledgments
or SACK options) and that there are no unacknowledged
retransmissions.
tcpESDataUnordered(2) indicates that the remote receiver is
reporting missing or out-of-order data (sending duplicate
acknowledgments or SACK options) and that there are no
unacknowledged retransmissions (because the missing data
has not yet been retransmitted).
tcpESDataRecovery(3) indicates that the sender has
outstanding retransmitted data which is still in flight
(i.e. is still unacknowledged).
tcpEStatsStackInRecovery is a required precondition for
some algorithms on other instruments. E.g. Some algorithms
to estimate path properties may not be valid during
recovery."
::= { tcpEStatsStackEntry 13 }
tcpEStatsStackDupAcksIn OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of duplicate ACKs received."
::= { tcpEStatsStackEntry 14 }
tcpEStatsStackSpuriousFrDetected OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of acknowledgments reporting out-of-order
segments after the Fast Retransmit algorithm has already
retransmitted the segments. (For example as detected by the
Eiffle algorithm, [RFC3522]).'"
::= { tcpEStatsStackEntry 15 }
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tcpEStatsStackSpuriousRtoDetected OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of acknowledgments reporting segments that have
already be retransmitted due to a Retransmission Timeout."
::= { tcpEStatsStackEntry 16 }
--
-- The following optional objects reflect the options
-- requested on the SYN and/or SYN-ACK. These are useful for
-- debugging problems with TCP option negotiation.
--
tcpEStatsStackMSSSent OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value sent in an MSS option, or zero if none."
::= { tcpEStatsStackEntry 21 }
tcpEStatsStackMSSRcvd OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value received in an MSS option, or zero if none."
::= { tcpEStatsStackEntry 22 }
tcpEStatsStackWinScaleSent OBJECT-TYPE
SYNTAX Integer32 (-1..14)
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of the transmitted window scale option if one was
sent; otherwise, a value of -1. See [RFC1323]."
::= { tcpEStatsStackEntry 23 }
tcpEStatsStackWinScaleRcvd OBJECT-TYPE
SYNTAX Integer32 (-1..14)
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of the received window scale option if one was
received; otherwise, a value of -1. See [RFC1323]."
::= { tcpEStatsStackEntry 24 }
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tcpEStatsStackSACKokSent OBJECT-TYPE
SYNTAX TruthValue
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"True(1) if SACKok option was sent, else false(2). See
[RFC2018]."
::= { tcpEStatsStackEntry 25 }
tcpEStatsStackSACKokRcvd OBJECT-TYPE
SYNTAX TruthValue
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"True(1) if SACKok option was received, else false(2). See
[RFC2018]."
::= { tcpEStatsStackEntry 26 }
tcpEStatsStackTimeStampSent OBJECT-TYPE
SYNTAX TruthValue
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"True(1) if Timestamp option was sent, else false(2). See
[RFC1323]."
::= { tcpEStatsStackEntry 27 }
tcpEStatsStackTimeStampRcvd OBJECT-TYPE
SYNTAX TruthValue
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"True(1) if Timestamp option was received, else false(2).
See [RFC1323]."
::= { tcpEStatsStackEntry 28 }
--
-- The following optional objects instrument unusual protocol
-- events that probably indicate implementation problems in
-- the protocol or path.
--
tcpEStatsStackSoftErrors OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of segments that fail various consistency tests
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during TCP input processing. Soft errors might cause the
segment to be discard but some do not. Some of these soft
errors cause the generation of a TCP acknowledgment, others
are silently discarded."
::= { tcpEStatsStackEntry 29 }
tcpEStatsStackSoftErrorReason OBJECT-TYPE
SYNTAX INTEGER {
belowDataWindow(1),
aboveDataWindow(2),
belowAckWindow(3),
aboveAckWindow(4),
belowTSWindow(5),
aboveTSWindow(6),
dataCheckSum(7),
otherSoftError(8)
}
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This object identities which consistency test most recently
failed during tcp input processing. This object should be
set every time tcpEStatsStackSoftErrors is incremented. The
codes are as follows:
belowDataWindow - All data in the segment is below SND.UNA.
(Normal for keep-alives and possibly zero window probes).
aboveDataWindow - Some data in the segment is above
SND.WND. (Indicates an implementation bug or serious
fraud).
belowAckWindow - ACK below SND.UNA. (Indicates that the
return path is reordering ACKs)
aboveAckWindow - An ACK for data that we have not sent.
(Indicates an implementation bug or serious fraud).
belowTSWindow - TSecr on the segment is older than the
current TS.Recent [RFC1323] (Normal for the rare case where
PAWS detects data reordered by the network.)
aboveTSWindow - TSecr on the segment is newer than the
current TS.Recent [RFC1323]. (Indicates an implementation
bug or serious fraud).
dataCheckSum - Incorrect checksum. Note that this value is
intrinsically fragile, because the header fields used to
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identify the connection may have been corrupted.
otherSoftError - All other soft errors.
Implementors are permitted to assign additional codes
greater than 8 such that all SoftErrors in their
implementation have unique codes. Management stations are
to accumulate all unassigned codes as 'otherSoftErrors'"
::= { tcpEStatsStackEntry 30 }
--
-- The following optional initial value objects are useful for
-- conformance testing instruments on application progress and
-- consumed network resources.
--
tcpEStatsStackSndInitial OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Initial send sequence number. Note that by definition
tcpEStatsStackSndInitial never changes for a given
connection. See [RFC793]."
::= { tcpEStatsStackEntry 31 }
tcpEStatsStackRecInitial OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Initial receive sequence number. Note that by definition
tcpEStatsStackRecInitial never changes for a given
connection. See [RFC793]."
::= { tcpEStatsStackEntry 32 }
--
-- The following optional objects expose the detailed
-- operation of the congestion control algorithms.
--
tcpEStatsStackSlowStart OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of times the congestion window has been
increased by the Slow Start algorithm. See [RFC2581]."
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::= { tcpEStatsStackEntry 33 }
tcpEStatsStackCongAvoid OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of times the congestion window has been
increased by the Congestion Avoidance algorithm. See
[RFC2581]."
::= { tcpEStatsStackEntry 34 }
tcpEStatsStackOtherReductions OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of congestion window reductions made as a result
of anything other than AIMD congestion control algorithms.
Examples of non-multiplicative window reductions include
experimental algorithms such as Vegas [Bra94], and
Congestion Window Validation [RFC2861].
All window reductions MUST be counted as either
tcpEStatsPerfCongSignals or tcpEStatsStackOtherReductions."
::= { tcpEStatsStackEntry 35 }
tcpEStatsStackCongOverCount OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of congestion events which were 'backed out' of
the congestion control state machine such that the
congestion window was restored to a prior value. This can
happen due to the Eiffle algorithm [RFC3522] or other
algorithms which can be used to detect and cancel spurious
invocations of the Fast Retransmit Algorithm.
Although it may be feasible to undo the effects of spurious
invocation of the Fast Retransmit congestion events can not
easily be backed out of tcpEStatsPerfCongSignals and
tcpEStatsPathPreCongSumCwnd, etc."
::= { tcpEStatsStackEntry 36 }
tcpEStatsStackFastRetran OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
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STATUS current
DESCRIPTION
"The number of invocations of the Fast Retransmit algorithm.
See [RFC2581]."
::= { tcpEStatsStackEntry 37 }
tcpEStatsStackSubsequentTimeouts OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of times the retransmit timeout has expired
after the RTO has been doubled. See 5.5 of [RFC2988]."
::= { tcpEStatsStackEntry 38 }
tcpEStatsStackCurTimeoutCount OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current number of times the retransmit timeout has
expired without receiving an acknowledgment for new data.
tcpEStatsStackCurTimeoutCount is reset to zero when new
data is acknowledged and incremented for each invocation of
section 5.5 in [RFC2988]."
::= { tcpEStatsStackEntry 39 }
tcpEStatsStackAbruptTimeouts OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of timeouts that occurred without any
immediately preceding duplicate acknowledgments or other
indications of congestion. Abrupt Timeouts indicate that
the path lost an entire window of data or acknowledgments.
Timeouts that are preceded by duplicate acknowledgments or
other congestion signals (e.g. ECN) are not counted as
abrupt, and might have been avoided by a more sophisticated
Fast Retransmit algorithm."
::= { tcpEStatsStackEntry 40 }
tcpEStatsStackSACKsRcvd OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
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"The number of SACK options received. See [RFC2018]."
::= { tcpEStatsStackEntry 41 }
tcpEStatsStackSACKBlocksRcvd OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of SACK blocks received (within SACK options)."
::= { tcpEStatsStackEntry 42 }
tcpEStatsStackSendStall OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of interface stalls or other sender local
resource limitations that are treated as congestion
signals."
::= { tcpEStatsStackEntry 43 }
tcpEStatsStackDSACKDups OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of duplicate segments reported to the local host
by D-SACK blocks. See [RFC2883]."
::= { tcpEStatsStackEntry 44 }
--
-- The following optional objects instrument path MTU
-- discovery.
--
tcpEStatsStackMaxMSS OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum MSS, in octets. See [RFC1191]."
::= { tcpEStatsStackEntry 45 }
tcpEStatsStackMinMSS OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
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"The minimum MSS, in octets. See [RFC1191]."
::= { tcpEStatsStackEntry 46 }
--
-- The following optional objects instrument the senders
-- buffer usage, including any buffering in the application
-- interface to TCP and the retransmit queue. All 'buffer
-- memory' instruments are assumed to include OS data
-- structure overhead.
--
tcpEStatsStackCurRetxQueue OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current number of octets of data occupying the
retransmit queue."
::= { tcpEStatsStackEntry 47 }
tcpEStatsStackMaxRetxQueue OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum number of octets of data occupying the
retransmit queue."
::= { tcpEStatsStackEntry 48 }
tcpEStatsStackCurReasmQueue OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current number of octets of sequence space spanned by
the reassembly queue. This is generally the difference
between rcv.nxt and the sequence number of the right most
edge of the reassembly queue."
::= { tcpEStatsStackEntry 49 }
tcpEStatsStackMaxReasmQueue OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum value of tcpEStatsStackCurReasmQueue"
::= { tcpEStatsStackEntry 50 }
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-- ================================================================
--
-- Statistics for diagnosing interactions between
-- applications and TCP.
--
tcpEStatsAppTable OBJECT-TYPE
SYNTAX SEQUENCE OF TcpEStatsAppEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table contains objects that are useful for
determining if the application using TCP is
limiting TCP performance"
::= { tcpEStats 5 }
tcpEStatsAppEntry OBJECT-TYPE
SYNTAX TcpEStatsAppEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"Each entry in this table has information about the
characteristics of each active and recently closed tcp
connection."
INDEX { tcpEStatsConnectIndex }
::= { tcpEStatsAppTable 1 }
TcpEStatsAppEntry ::= SEQUENCE {
tcpEStatsAppSndUna Counter32,
tcpEStatsAppSndNxt Integer32,
tcpEStatsAppSndMax Counter32,
tcpEStatsAppThruOctetsAcked ZeroBasedCounter32,
tcpEStatsAppHCThruOctetsAcked ZeroBasedCounter64,
tcpEStatsAppRcvNxt Counter32,
tcpEStatsAppThruOctetsReceived ZeroBasedCounter32,
tcpEStatsAppHCThruOctetsReceived ZeroBasedCounter64,
tcpEStatsAppCurAppWQueue Gauge32,
tcpEStatsAppMaxAppWQueue Gauge32,
tcpEStatsAppCurAppRQueue Gauge32,
tcpEStatsAppMaxAppRQueue Gauge32
}
--
-- The following objects provide throughput statistics for the
-- connection including sequence numbers and elapsed
-- application data. These permit direct observation of the
-- applications progress, in terms of elapsed data delivery
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-- and elapsed time. See [RFC793].
--
tcpEStatsAppSndUna OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of SND.UNA, the oldest unacknowledged sequence
number."
::= { tcpEStatsAppEntry 1 }
tcpEStatsAppSndNxt OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of SND.NXT, the next sequence number to be sent.
Note that tcpEStatsAppSndNxt is not a monotonic (and thus
not a counter) because TCP sometimes retransmits lost data
by pulling tcpEStatsAppSndNxt back to the missing data."
::= { tcpEStatsAppEntry 2 }
tcpEStatsAppSndMax OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The farthest forward (right most or largest) SND.NXT value.
Note that this will be equal to tcpEStatsAppSndNxt except
when tcpEStatsAppSndNxt is pulled back during recovery."
::= { tcpEStatsAppEntry 3 }
tcpEStatsAppThruOctetsAcked OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of octets for which cumulative acknowledgments
have been received. Note that this will be the sum of
changes to tcpEStatsAppSndUna."
::= { tcpEStatsAppEntry 4 }
tcpEStatsAppHCThruOctetsAcked OBJECT-TYPE
SYNTAX ZeroBasedCounter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
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"The number of octets for which cumulative acknowledgments
have been received, on systems that can receive more than
10 million bits per second. Note that this will be the sum
of changes in tcpEStatsAppSndUna."
::= { tcpEStatsAppEntry 5 }
tcpEStatsAppRcvNxt OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of RCV.NXT from [RFC793]. The next sequence
number expected on an incoming segment, and the left or
lower edge of the receive window."
::= { tcpEStatsAppEntry 6 }
tcpEStatsAppThruOctetsReceived OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of octets for which cumulative acknowledgments
have been sent. Note that this will be the sum of changes
to tcpEStatsAppRcvNxt."
::= { tcpEStatsAppEntry 7 }
tcpEStatsAppHCThruOctetsReceived OBJECT-TYPE
SYNTAX ZeroBasedCounter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of octets for which cumulative acknowledgments
have been sent, on systems that can transmit more than 10
million bits per second. Note that this will be the sum of
changes in tcpEStatsAppRcvNxt."
::= { tcpEStatsAppEntry 8 }
tcpEStatsAppCurAppWQueue OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current number of octets of application data buffered
by TCP, pending first transmission, i.e. to the left of
SND.NXT or SndMax. This data will generally be transmitted
(and SND.NXT advanced to the left) as soon as there is
available congestion window (cwnd) or receiver window
(rwin). This is the amount of data readily available for
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transmission, without scheduling the application. TCP
performance may suffer if there is insufficient queued
write data."
::= { tcpEStatsAppEntry 21 }
tcpEStatsAppMaxAppWQueue OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum number of octets of application data buffered
by TCP, pending first transmission. This is the maximum
value of tcpEStatsAppCurAppWQueue. This pair of objects can
be used to determine if insufficient queued data is steady
state (suggesting insufficient queue space) or transient
(suggesting insufficient application performance or
excessive CPU load or scheduler latency)."
::= { tcpEStatsAppEntry 22 }
tcpEStatsAppCurAppRQueue OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current number of octets of application data that has
been acknowledged by TCP but not yet delivered to the
application."
::= { tcpEStatsAppEntry 23 }
tcpEStatsAppMaxAppRQueue OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum number of octets of application data that has
been acknowledged by TCP but not yet delivered to the
application."
::= { tcpEStatsAppEntry 24 }
-- ================================================================
--
-- Controls for Tuning TCP
--
tcpEStatsTuneTable OBJECT-TYPE
SYNTAX SEQUENCE OF TcpEStatsTuneEntry
MAX-ACCESS not-accessible
STATUS current
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DESCRIPTION
"This table contains per connection controls that can
be used to work around a number of common problems that
plague TCP over some paths. All can be characterized as
limiting the growth of the congestion window so as to
prevent TCP from overwhelming some component in the path."
::= { tcpEStats 6 }
tcpEStatsTuneEntry OBJECT-TYPE
SYNTAX TcpEStatsTuneEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"Each entry in this table is a control that can be used to
place limits on each active tcp connection."
INDEX { tcpEStatsConnectIndex }
::= { tcpEStatsTuneTable 1 }
TcpEStatsTuneEntry ::= SEQUENCE {
tcpEStatsTuneLimCwnd Gauge32,
tcpEStatsTuneLimSsthresh Gauge32,
tcpEStatsTuneLimRwin Gauge32
}
tcpEStatsTuneLimCwnd OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"A control to set the maximum congestion window which may be
used, in octets."
::= { tcpEStatsTuneEntry 1 }
tcpEStatsTuneLimSsthresh OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"A control to limit the maximum queue space (in octets) that
this TCP connection is likely to occupy during slowstart.
It can be implemented with the algorithm described in
RFC3742 by setting the max_ssthresh parameter to twice
tcpEStatsTuneLimSsthresh.
This algorithm can be used to overcome some TCP performance
problems over network paths that do not have sufficient
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buffering to withstand the bursts normally present during
slowstart."
::= { tcpEStatsTuneEntry 2 }
tcpEStatsTuneLimRwin OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"A control to set the maximum window advertisement which may
be sent, in octets."
::= { tcpEStatsTuneEntry 3 }
-- ================================================================
--
-- TCP Extended Statistics Notifications Group
--
tcpEStatsEstablishNotification NOTIFICATION-TYPE
OBJECTS {
tcpEStatsConnectIndex
}
STATUS current
DESCRIPTION
"The indicated connection has been accepted
(or alternatively entered the established state)."
::= { tcpEStatsNotifications 1 }
tcpEStatsCloseNotification NOTIFICATION-TYPE
OBJECTS {
tcpEStatsConnectIndex
}
STATUS current
DESCRIPTION
"The indicated connection has left the
established state"
::= { tcpEStatsNotifications 2 }
-- ================================================================
--
-- Conformance Definitions
--
tcpEStatsCompliances OBJECT IDENTIFIER
::= { tcpEStatsConformance 1 }
tcpEStatsGroups OBJECT IDENTIFIER
::= { tcpEStatsConformance 2 }
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--
-- Compliance Statements
--
tcpEStatsCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"Compliance statement for all systems that implement TCP
extended statistics."
MODULE -- this module
MANDATORY-GROUPS {
tcpEStatsListenerGroup,
tcpEStatsConnectIdGroup,
tcpEStatsPerfGroup,
tcpEStatsPathGroup,
tcpEStatsStackGroup,
tcpEStatsAppGroup
}
GROUP tcpEStatsListenerHCGroup
DESCRIPTION
"This group is mandatory for all systems that can
wrap the values of the 32-bit counters in
tcpEStatsListenerGroup in less than one hour."
GROUP tcpEStatsPerfOptionalGroup
DESCRIPTION
"This group is optional for all systems."
GROUP tcpEStatsPerfHCGroup
DESCRIPTION
"This group is mandatory for systems that can
wrap the values of the 32-bit counters in
tcpEStatsPerfGroup in less than one hour.
Note that any system that can attain 10 Mb/s
can potentially wrap 32-Bit Octet counters in
under one hour."
GROUP tcpEStatsPathOptionalGroup
DESCRIPTION
"This group is optional for all systems."
GROUP tcpEStatsPathHCGroup
DESCRIPTION
"This group is mandatory for systems that can
wrap the values of the 32-bit counters in
tcpEStatsPathGroup in less than one hour.
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Note that any system that can attain 10 Mb/s
can potentially wrap 32-Bit Octet counters in
under one hour."
GROUP tcpEStatsStackOptionalGroup
DESCRIPTION
"This group is optional for all systems."
GROUP tcpEStatsAppHCGroup
DESCRIPTION
"This group is mandatory for systems that can
wrap the values of the 32-bit counters in
tcpEStatsStackGroup in less than one hour.
Note that any system that can attain 10 Mb/s
can potentially wrap 32-Bit Octet counters in
under one hour."
GROUP tcpEStatsAppOptionalGroup
DESCRIPTION
"This group is optional for all systems."
GROUP tcpEStatsTuneOptionalGroup
DESCRIPTION
"This group is optional for all systems."
GROUP tcpEStatsNotificationsGroup
DESCRIPTION
"This group is optional for all systems."
GROUP tcpEStatsNotificationsCtlGroup
DESCRIPTION
"This group is mandatory for systems that include the
tcpEStatsNotificationGroup."
OBJECT tcpEStatsControlNotify
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
::= { tcpEStatsCompliances 1 }
-- ================================================================
--
-- Units of Conformance
--
tcpEStatsListenerGroup OBJECT-GROUP
OBJECTS {
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tcpEStatsListenerTableLastChange,
tcpEStatsListenerStartTime,
tcpEStatsListenerSynRcvd,
tcpEStatsListenerInitial,
tcpEStatsListenerEstablished,
tcpEStatsListenerAccepted,
tcpEStatsListenerExceedBacklog,
tcpEStatsListenerCurrConns,
tcpEStatsListenerMaxBacklog,
tcpEStatsListenerCurBacklog,
tcpEStatsListenerCurEstabBacklog
}
STATUS current
DESCRIPTION
"The tcpEStatsListener group includes objects that
provide valuable statistics and debugging
information for TCP Listeners."
::= { tcpEStatsGroups 1 }
tcpEStatsListenerHCGroup OBJECT-GROUP
OBJECTS {
tcpEStatsListenerHCSynRcvd,
tcpEStatsListenerHCInitial,
tcpEStatsListenerHCEstablished,
tcpEStatsListenerHCAccepted,
tcpEStatsListenerHCExceedBacklog
}
STATUS current
DESCRIPTION
"The tcpEStatsListenerHC group includes 64 bit
counters in tcpEStatsListenerTable."
::= { tcpEStatsGroups 2 }
tcpEStatsConnectIdGroup OBJECT-GROUP
OBJECTS {
tcpEStatsConnTableLatency,
tcpEStatsConnectIndex
}
STATUS current
DESCRIPTION
"The tcpEStatsConnectId group includes objects that
identify TCP connections and control how long TCP
connection entries are retained in the tables."
::= { tcpEStatsGroups 3 }
tcpEStatsPerfGroup OBJECT-GROUP
OBJECTS {
tcpEStatsPerfSegsOut, tcpEStatsPerfDataSegsOut,
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tcpEStatsPerfDataOctetsOut,
tcpEStatsPerfSegsRetrans,
tcpEStatsPerfOctetsRetrans, tcpEStatsPerfSegsIn,
tcpEStatsPerfDataSegsIn,
tcpEStatsPerfDataOctetsIn,
tcpEStatsPerfElapsedSecs,
tcpEStatsPerfElapsedMicroSecs,
tcpEStatsPerfStartTimeStamp, tcpEStatsPerfCurMSS,
tcpEStatsPerfPipeSize, tcpEStatsPerfMaxPipeSize,
tcpEStatsPerfSmoothedRTT, tcpEStatsPerfCurRTO,
tcpEStatsPerfCongSignals, tcpEStatsPerfCurCwnd,
tcpEStatsPerfCurSsthresh, tcpEStatsPerfTimeouts,
tcpEStatsPerfCurRwinSent,
tcpEStatsPerfMaxRwinSent,
tcpEStatsPerfZeroRwinSent,
tcpEStatsPerfCurRwinRcvd,
tcpEStatsPerfMaxRwinRcvd,
tcpEStatsPerfZeroRwinRcvd
}
STATUS current
DESCRIPTION
"The tcpEStatsPerf group includes those objects that
provide basic performance data for a TCP connection."
::= { tcpEStatsGroups 4 }
tcpEStatsPerfOptionalGroup OBJECT-GROUP
OBJECTS {
tcpEStatsPerfSndLimTransRwin,
tcpEStatsPerfSndLimTransCwnd,
tcpEStatsPerfSndLimTransSnd,
tcpEStatsPerfSndLimTimeRwin,
tcpEStatsPerfSndLimTimeCwnd,
tcpEStatsPerfSndLimTimeSnd
}
STATUS current
DESCRIPTION
"The tcpEStatsPerf group includes those objects that
provide basic performance data for a TCP connection."
::= { tcpEStatsGroups 5 }
tcpEStatsPerfHCGroup OBJECT-GROUP
OBJECTS {
tcpEStatsPerfHCDataOctetsOut,
tcpEStatsPerfHCDataOctetsIn
}
STATUS current
DESCRIPTION
"The tcpEStatsPerfHC group includes 64 bit
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counters in the tcpEStatsPerfTable."
::= { tcpEStatsGroups 6 }
tcpEStatsPathGroup OBJECT-GROUP
OBJECTS {
tcpEStatsControlPath,
tcpEStatsPathRetranThresh,
tcpEStatsPathNonRecovDAEpisodes,
tcpEStatsPathSumOctetsReordered,
tcpEStatsPathNonRecovDA
}
STATUS current
DESCRIPTION
"The tcpEStatsPath group includes objects that
control the creation of the tcpEStatsPathTable,
and provide information about the path
for each TCP connection."
::= { tcpEStatsGroups 7 }
tcpEStatsPathOptionalGroup OBJECT-GROUP
OBJECTS {
tcpEStatsPathSampleRTT, tcpEStatsPathRTTVar,
tcpEStatsPathMaxRTT, tcpEStatsPathMinRTT,
tcpEStatsPathSumRTT, tcpEStatsPathCountRTT,
tcpEStatsPathMaxRTO, tcpEStatsPathMinRTO,
tcpEStatsPathIpTtl, tcpEStatsPathIpTosIn,
tcpEStatsPathIpTosOut,
tcpEStatsPathPreCongSumCwnd,
tcpEStatsPathPreCongSumRTT,
tcpEStatsPathPostCongSumRTT,
tcpEStatsPathPostCongCountRTT,
tcpEStatsPathECNsignals, tcpEStatsPathECERcvd,
tcpEStatsPathQuenchRcvd,
tcpEStatsPathDupAckEpisodes,
tcpEStatsPathDupAcksOut, tcpEStatsPathCERcvd,
tcpEStatsPathECNSent, tcpEStatsPathECNNonceRcvd
}
STATUS current
DESCRIPTION
"The tcpEStatsPath group includes objects that
provide additional information about the path
for each TCP connection."
::= { tcpEStatsGroups 8 }
tcpEStatsPathHCGroup OBJECT-GROUP
OBJECTS {
tcpEStatsPathHCSumRTT
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}
STATUS current
DESCRIPTION
"The tcpEStatsPathHC group includes 64 bit
counters in the tcpEStatsPathTable."
::= { tcpEStatsGroups 9 }
tcpEStatsStackGroup OBJECT-GROUP
OBJECTS {
tcpEStatsControlStack,
tcpEStatsStackState, tcpEStatsStackSACK,
tcpEStatsStackTimeStamps, tcpEStatsStackECN,
tcpEStatsStackNagle, tcpEStatsStackSndWindScale,
tcpEStatsStackRcvWindScale,
tcpEStatsStackActiveOpen, tcpEStatsStackMaxSsCwnd,
tcpEStatsStackMaxCaCwnd,
tcpEStatsStackMaxSsthresh,
tcpEStatsStackMinSsthresh,
tcpEStatsStackInRecovery, tcpEStatsStackDupAcksIn,
tcpEStatsStackSpuriousFrDetected,
tcpEStatsStackSpuriousRtoDetected
}
STATUS current
DESCRIPTION
"The tcpEStatsConnState group includes objects that
control the creation of the tcpEStatsStackTable,
and provide information about the operation of
algorithms used within TCP."
::= { tcpEStatsGroups 10 }
tcpEStatsStackOptionalGroup OBJECT-GROUP
OBJECTS {
tcpEStatsStackMSSSent, tcpEStatsStackMSSRcvd,
tcpEStatsStackWinScaleSent,
tcpEStatsStackWinScaleRcvd,
tcpEStatsStackSACKokSent,
tcpEStatsStackSACKokRcvd,
tcpEStatsStackTimeStampSent,
tcpEStatsStackTimeStampRcvd,
tcpEStatsStackSoftErrors,
tcpEStatsStackSoftErrorReason,
tcpEStatsStackSndInitial,
tcpEStatsStackRecInitial, tcpEStatsStackSlowStart,
tcpEStatsStackCongAvoid,
tcpEStatsStackOtherReductions,
tcpEStatsStackCongOverCount,
tcpEStatsStackFastRetran,
tcpEStatsStackSubsequentTimeouts,
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tcpEStatsStackCurTimeoutCount,
tcpEStatsStackAbruptTimeouts,
tcpEStatsStackSACKsRcvd,
tcpEStatsStackSACKBlocksRcvd,
tcpEStatsStackSendStall, tcpEStatsStackDSACKDups,
tcpEStatsStackMaxMSS, tcpEStatsStackMinMSS,
tcpEStatsStackCurRetxQueue,
tcpEStatsStackMaxRetxQueue,
tcpEStatsStackCurReasmQueue,
tcpEStatsStackMaxReasmQueue
}
STATUS current
DESCRIPTION
"The tcpEStatsConnState group includes objects that
provide additional information about the operation of
algorithms used within TCP."
::= { tcpEStatsGroups 11 }
tcpEStatsAppGroup OBJECT-GROUP
OBJECTS {
tcpEStatsControlApp,
tcpEStatsAppSndUna, tcpEStatsAppSndNxt,
tcpEStatsAppSndMax, tcpEStatsAppThruOctetsAcked,
tcpEStatsAppRcvNxt,
tcpEStatsAppThruOctetsReceived
}
STATUS current
DESCRIPTION
"The tcpEStatsConnState group includes objects that
control the creation of the tcpEStatsAppTable,
and provide information about the operation of
algorithms used within TCP."
::= { tcpEStatsGroups 12 }
tcpEStatsAppHCGroup OBJECT-GROUP
OBJECTS {
tcpEStatsAppHCThruOctetsAcked,
tcpEStatsAppHCThruOctetsReceived
}
STATUS current
DESCRIPTION
"The tcpEStatsStackHC group includes 64 bit
counters in the tcpEStatsStackTable."
::= { tcpEStatsGroups 13 }
tcpEStatsAppOptionalGroup OBJECT-GROUP
OBJECTS {
tcpEStatsAppCurAppWQueue,
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tcpEStatsAppMaxAppWQueue,
tcpEStatsAppCurAppRQueue,
tcpEStatsAppMaxAppRQueue
}
STATUS current
DESCRIPTION
"The tcpEStatsConnState group includes objects that
provide additional information about how applications
are interacting with each TCP connection."
::= { tcpEStatsGroups 14 }
tcpEStatsTuneOptionalGroup OBJECT-GROUP
OBJECTS {
tcpEStatsControlTune,
tcpEStatsTuneLimCwnd, tcpEStatsTuneLimSsthresh,
tcpEStatsTuneLimRwin
}
STATUS current
DESCRIPTION
"The tcpEStatsConnState group includes objects that
control the creation of the tcpEStatsConnectionTable,
which can be used to set tuning parameters
for each TCP connection."
::= { tcpEStatsGroups 15 }
tcpEStatsNotificationsGroup NOTIFICATION-GROUP
NOTIFICATIONS {
tcpEStatsEstablishNotification,
tcpEStatsCloseNotification
}
STATUS current
DESCRIPTION
"Notifications sent by a TCP extended statistics agent."
::= { tcpEStatsGroups 16 }
tcpEStatsNotificationsCtlGroup OBJECT-GROUP
OBJECTS {
tcpEStatsControlNotify
}
STATUS current
DESCRIPTION
"The tcpEStatsNotificationsCtl group includes the
object that controls the creation of the events
in the tcpEStatsNotificationsGroup."
::= { tcpEStatsGroups 17 }
END
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5. Normative References
[RFC2574] U. Blumenthal, B. Wijnen, "User-based Security Model (USM) for
version 3 of the Simple Network Management Protocol (SNMPv3)",
RFC2574, April 1999.
[RFC2575] Wijnen, B., Presuhn, R., and K. McCloghrie, "View-based Access
Control Model (VACM) for the Simple Network Management Protocol
(SNMP)", RFC 2575, April 1999.
[RFC2578] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J.,
Rose, M., and S. Waldbusser, "Structure of Management Information
Version 2 (SMIv2)", STD 58, RFC 2578, April 1999.
[RFC2579] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J.,
Rose, M., and S. Waldbusser, "Textual Conventions for SMIv2", STD
58, RFC 2579, April 1999.
[RFC2580] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J.,
Rose, M., and S. Waldbusser, "Conformance Statements for SMIv2",
STD 58, RFC 2580, April 1999.
[RFC4022] Raghunarayan, R., "Management Information Base for the Trans-
mission Control Protocol (TCP)", RFC 4022, March 2005.
6. Informative References
[Mat97] M. Mathis, J. Semke, J. Mahdavi, T. Ott, "The Macroscopic Behav-
ior of the TCP Congestion Avoidance Algorithm", Computer Communica-
tion Review, volume 27, number3, July 1997.
[Bra94] Brakmo, L., O'Malley, S., "TCP Vegas, New Techniques for Conges-
tion Detection and Avoidance," SIGCOMM'94, London, pp 24-35, Octo-
ber 1994.
[POSIX] Portable Operating System Interface, IEEE Std 1003.1
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[Pad98] Padhye, J., Firoiu, V., Towsley, D., Kurose, J., "Modeling TCP
Throughput: A Simple Model and its Empirical Validation", SIG-
COMM'98
[Web100] Mathis, M., J. Heffner, R. Reddy, "Web100: Extended TCP Instru-
mentation for Research, Education and Diagnosis", ACM Computer Com-
munications Review, Vol 33, Num 3, July 2003.
[RFC793] J. Postel Ed., "Transmission Control Protocol", Sep 1981.
[RFC896] J. Nagle, "Congestion control in IP/TCP internetworks",
Jan-06-1984.
[RFC1122] R. Braden, Ed, "Requirements for Internet Hosts - Communica-
tion Layers", October 1989.
[RFC1191] J.C. Mogul, S.E. Deering, "Path MTU discovery", Nov-01-1990.
[RFC1323] V. Jacobson, R. Braden, D. Borman, "TCP Extensions for High
Performance", May 1992.
[RFC2018] M. Mathis, J. Mahdavi, S. Floyd, A. Romanow, "TCP Selective
Acknowledgment Options", October 1996.
[RFC2021] S. Waldbusser, "Remote Network Monitoring Management Informa-
tion Base Version 2 using SMIv2", January 1997.
[RFC2474] K. Nichols, S. Blake, F. Baker, D. Black, "Definition of the
Differentiated Services Field (DS Field) in the IPv4 and IPv6 Head-
ers", December 1998.
[RFC2856] A. Bierman, K. McCloghrie, R. Presuhn, "Textual Conventions
for Additional High Capacity Data Types", June 2000.
[RFC2861] M. Handley, J. Padhye, S. Floyd, "TCP Congestion Window Vali-
dation", June 2000.
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[RFC2883] S. Floyd, J. Mahdavi, M. Mathis, M. Podolsky, "An Extension to
the Selective Acknowledgment (SACK) Option for TCP", July 2000.
[RFC3168] K. Ramakrishnan, S. Floyd, D. Black, "The Addition of Explicit
Congestion Notification (ECN) to IP", September 2001.
[RFC3260] D. Grossman, "New Terminology and Clarifications for Diff-
serv", April 2002.
[RFC3410] Case, J., Mundy, R., Partain, D. and B. Stewart, "Introduction
and Applicability Statements for Internet-Standard Management
Framework", RFC 3410, December 2002.
[RFC3522] R. Ludwig, M. Meyer, "The Eifel Detection Algorithm for TCP",
April 2003.
[RFC2581] M. Allman, V. Paxson, W. Stevens, "TCP Congestion Control",
April 1999.
[RFC2988] V. Paxson, M. Allman, "Computing TCP's Retransmission Timer",
November 2000.
[RFC3291] M. Daniele, B. Haberman, S. Routhier, J. Schoenwaelder, "Tex-
tual Conventions for Internet Network Addresses", May 2002.
[RFC4001] Daniele, M., Haberman, B., Routhier, S., and J. Schoenwaelder,
"Textual Conventions for Internet Network Addresses", RFC 3291, May
2002.
7. Security Considerations
There are a number of management objects defined in this MIB that
have a MAX-ACCESS clause of read-write and/or read-create. Such
objects may be considered sensitive or vulnerable in some network
environments. The support for SET operations in a non-secure
environment without proper protection can have a negative effect on
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network operations.
There are a number of managed objects in this MIB that may contain
sensitive information. These are:
tcpEStatsConnectRemAddress tcpEStatsAppSndUna tcpEStatsAppSndNxt
tcpEStatsAppSndMax tcpEStatsStackSndInitial tcpEStatsAppRcvNxt
tcpEStatsStackRecInitial
It is thus important to control even GET access to these objects and
possibly to even encrypt the values of these objects when sending
them over the network via SNMP. Not all versions of SNMP provide
features for such a secure environment. SNMPv1 by itself is not a
secure environment. Even if the network itself is secure (for
example by using IPSec) there is no control as to who on the secure
network is allowed to access and GET/SET (read/change/create/delete)
the objects in this MIB.
It is recommended that implementers consider using the security
features as provided by the SNMPv3 framework. Specifically, the use
of the User-based Security Model RFC 2574 [RFC2574] and the View-
based Access Control Model RFC 2575 [RFC2575] is recommended.
It is then a customer/user responsibility to ensure that the SNMP
entity giving access to an instance of this MIB, is properly
configured to only give access to the objects to those principals
(users) that have legitimate rights to indeed GET or SET
(change/create/delete) them.
8. Contributors
The following people contributed text that was incorporated into this
document:
Jon Saperia <saperia@jdscons.com> converted Web100 internal
documentation into a true MIB. Jon can be reached at JDS Consulting,
Inc, 617-744-1079.
Some of the objects in this document were moved from an early draft
of the TCP-MIB, by Bill Fenner et al.
Some of the object descriptions are based on an earlier unpublished
document by Jeff Semke.
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9. Acknowledgments
This document is a product of the Web100 project (www.web100.org), a
joint effort of the Pittsburgh Supercomputing Center (www.psc.edu),
National Center for Atmospheric Research (www.ncar.ucar.edu) and
National Center for Supercomputer Applications (www.ncsa.edu).
It would not have been possible without all of the hard work by the
the entire Web100 team, especially Peter O'Neal who read and reread
the entire document several times; Janet Brown and Marla Meehl, who
patiently managed the unmanageable. The Web100 project would not
have been successful without all of the early adopters who suffered
our bugs to provide many good suggestions and insights into their
needs for TCP instrumentation.
Web100 was supported by the National Science Foundation under Grant
No. 0083285 and a research grant from Cisco Systems.
We would also like to thank all of the people who built experimental
implementations of this MIB from early versions of the Internet Draft
and provided us with constructive feedback: Glenn Turner at AARnet,
Kristine Adamson at IBM and Xinyan Zan at Microsoft.
10. Authors' Addresses
Matt Mathis
John Heffner
Pittsburgh Supercomputing Center
4400 Fifth Ave
Pittsburgh, PA 15216
Phone: 412-268-4960
Email: mathis@web100.org, rreddy@psc.edu, jheffner@psc.edu
Rajiv Raghunarayan
Cisco Systems Inc.
San Jose, CA 95134
Phone: 408 853 9612
Email: raraghun@cisco.com
11. Intellectual Property
The IETF takes no position regarding the validity or scope of any
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to pertain to the implementation or use of the technology
described in this document or the extent to which any license
under such rights might or might not be available; nor does it
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represent that it has made any independent effort to identify any
such rights. Information on the procedures with respect to rights
in RFC documents can be found in BCP 78 and BCP 79.
Copies of IPR disclosures made to the IETF Secretariat and any
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The IETF invites any interested party to bring to its attention
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12. Disclaimer of Validity
This document and the information contained herein are provided
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13. Copyright Statement
Copyright (C) The Internet Society (2005).
This document is subject to the rights, licenses and restrictions
contained in BCP 78, and except as set forth therein, the authors
retain all their rights.
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