Simple Two-Way Direct Loss Measurement Procedure
draft-gandhi-ippm-simple-direct-loss-02
| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Authors | Rakesh Gandhi , Clarence Filsfils , Daniel Voyer , Mach Chen , Bart Janssens , Stefano Salsano | ||
| Last updated | 2022-02-04 | ||
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draft-gandhi-ippm-simple-direct-loss-02
IPPM Working Group R. Gandhi, Ed.
Internet-Draft C. Filsfils
Intended status: Standards Track Cisco Systems, Inc.
Expires: 8 August 2022 D. Voyer
Bell Canada
M. Chen
Huawei
B. Janssens
Colt
S. Salsano
Universita di Roma "Tor Vergata"
4 February 2022
Simple Two-Way Direct Loss Measurement Procedure
draft-gandhi-ippm-simple-direct-loss-02
Abstract
This document defines Simple Two-Way Direct Loss Measurement (DLM)
procedure that can be used for Alternate-Marking Method for detecting
accurate data packet loss in a network. Specifically, DLM probe
packets are defined for both unauthenticated and authenticated modes
and they are efficient for hardware-based implementation.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
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and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 8 August 2022.
Copyright Notice
Copyright (c) 2022 IETF Trust and the persons identified as the
document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions Used in This Document . . . . . . . . . . . . . . 4
2.1. Requirements Language . . . . . . . . . . . . . . . . . . 4
2.2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 4
2.3. Reference Topology . . . . . . . . . . . . . . . . . . . 5
3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4. Session-Sender Direct Loss Measurement Probe Packet . . . . . 6
5. Session-Reflector Direct Loss Measurement Probe Packet . . . 9
6. Data Loss Calculation . . . . . . . . . . . . . . . . . . . . 12
7. Optional Extensions . . . . . . . . . . . . . . . . . . . . . 12
8. Integrity Protection and Confidentiality Protection . . . . . 12
9. Operational Considerations . . . . . . . . . . . . . . . . . 13
10. Security Considerations . . . . . . . . . . . . . . . . . . . 13
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
12.1. Normative References . . . . . . . . . . . . . . . . . . 13
12.2. Informative References . . . . . . . . . . . . . . . . . 14
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
1. Introduction
Many Service Provider Service Level Agreements (SLAs) depend on the
ability to measure performance loss metric experienced by the
Customer data traffic flow. Accurate Customer data packet loss can
be measured by using a Direct Loss Measurement (DLM) procedure.
Currently there is no efficient active measurement procedure
available for accurate data packet loss detection in IP networks.
Note that an approach for conducting packet loss measurement in IP
networks is documented in [RFC7680]. This approach requires clock
synchronization between the measurement points and lacks support for
accurate data packet loss measurement.
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[ITU-Y1731] defines procedures for performance loss monitoring for
Ethernet-based networks. Specifically, the Loss Measurement Message
(LMM) defined in Section 9.12 of [ITU-Y1731] can be used for accurate
frame loss measurement as described in Appendix II of that document.
The procedure is specific to the Ethernet-based networks and does not
apply to the IP networks.
The Simple Two-Way Active Measurement Protocol (STAMP) provides
capabilities for the measurement of various performance metrics in IP
networks [RFC8762] without the use of a control channel to pre-signal
session parameters. The STAMP can be used for (synthetic or
inferred) packet loss measurement based on the Sequence Number in the
test packets, however, this method can only provide approximate
packet loss metrics.
[RFC8972] defines optional extensions for STAMP. The STAMP test
packet with the "Direct Measurement" TLV (Type 5) [RFC8972] can be
used for combined timestamps and data packet counters collection.
This method, however, has the following limitations when used for
detecting data packet loss:
* For only direct measurement, the STAMP "Direct Measurement" TLV in
the test packet requires the hardware to support timestamps, in
addition to data packet counters. One-way delay measurement also
requires clock synchronization between the Session-Sender and
Session-Reflector nodes.
* The location of the transmit counter is not at the fixed location
in the STAMP test packet with the "Direct Measurement" TLV. Also,
the location of the transmit counter on the STAMP Session-
Reflector reply test packet is not at the same location as the
STAMP Session-Sender test packet using the "Direct Measurement"
TLV. This makes it difficult to implement in hardware, e.g., for
point-to-point links and circuits.
* Furthermore, for hardware-based implementation, the optional
"Direct Measurement" TLV adds unnecessary processing overhead on
the Session-Reflector as not all STAMP Session-Sender test packets
carry the "Direct Measurement" TLV and also there can be multiple
TLV Types present.
* The STAMP "Direct Measurement" TLV does not support 64-bit
counters.
* The STAMP "Direct Measurement" TLV does not support counters for
bytes.
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* The STAMP "Direct Measurement" TLV does not support counters per
traffic class.
* The STAMP "Direct Measurement" TLV also does not identify the
Block Number of the Direct Measurement, which is required for
Alternate-Marking Method [RFC8321] for data packet loss
measurement. The AMM also handles the case of out-of-order data
packets.
This document defines Simple Two-Way Direct Loss Measurement (DLM)
procedure that can be used for Alternate-Marking Method [RFC8321] for
detecting accurate data packet loss in a network. Specifically, DLM
probe packets are defined for both unauthenticated and authenticated
modes and they are efficient for hardware-based implementation.
2. Conventions Used in This Document
2.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119] [RFC8174]
when, and only when, they appear in all capitals, as shown here.
2.2. Abbreviations
AMM: Alternate-Marking Method.
DLM: Direct Loss Measurement.
HMAC: Hashed Message Authentication Code.
MBZ: Must be Zero.
PM: Performance Measurement.
SHA: Secure Hash Algorithm.
SSID: Sender Session Identifier.
STAMP: Simple Two-Way Active Measurement Protocol.
TTL: Time To Live.
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2.3. Reference Topology
As shown in the reference topology, the Session-Sender S1 initiates a
Direct Loss Measurement (DLM) probe packet over UDP transport. The
Session-Reflector R1 receives the Session-Sender's DLM probe packet
and acts according to the local configuration. The Session-Reflector
R1 transmits a DLM reply probe packet to the Session-Sender S1.
C1 C2
/ \
+-------+ DLM Probe Packet +-------+
| | - - - - - - - - - - - ->| |
| S1 |=========================| R1 |
| |<- - - - - - - - - - - - | |
+-------+ DLM Reply Probe Packet +-------+
\ /
C4 C3
Session-Sender Session-Reflector
Reference Topology
3. Overview
For accurate data packet loss detection, the DLM probe packets are
transmitted by the Session-Sender over UDP transport, and are used to
collect the transmit and receive counters for the data traffic flow
under measurement. The DLM reply probe packets are transmitted by
the Session-Reflector to collect the transmit and receive counters
for the data traffic flow under measurement in the reverse direction.
The DLM probe packets carry user-configured destination UDP port.
The destination UDP port 862 is not used for the DLM probe packets.
The user-configured destination UDP port follows the guidelines
described in Section 4.1 of [RFC8762]. Different destination UDP
port is used for DLM probe packets than the STAMP test packets
defined in [RFC8762]. Hence, the Session-Sender and the Session-
Reflector do not require backwards compatibility and support for
STAMP.
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A DLM session is identified by the 4-tuple (source and destination IP
addresses, source and destination UDP port numbers). A DLM Session-
Sender MAY generate a locally unique Sender Session Identifier
(SSID). The SSID is a two-octet, non-zero unsigned integer. The
SSID generation policy is implementation specific. An implementation
MUST NOT assign the same identifier to different DLM sessions. A
Session-Sender MAY use the SSID to identify a DLM session. If the
SSID is used, it MUST be present in each probe packet of the given
DLM session.
The DLM Session-Reflector operates in the Stateless mode. The DLM
Session-Reflector does not maintain session state and will use the
value in the Sequence Number field in the received probe packet as
the value for the Sequence Number field in the reply probe packet.
As a result, values in the Sequence Number and Session-Sender
Sequence Number fields are the same in this mode.
In this document, the examples of DLM probe packets are shown with
UDP header, however, the packets can be encapsulated with a different
header based on the the transport protocol used in the network.
4. Session-Sender Direct Loss Measurement Probe Packet
In this document, base Session-Sender DLM probe packet formats are
defined as shown in Figure 1 and Figure 2 for unauthenticated and
authenticated modes, respectively. They are stand-alone DLM probe
packet formats to carry the counters for the data traffic flow under
measurement. The DLM probe packet formats are similar to the base
STAMP test packet formats (for example the locations of the Counters
and Timestamps).
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Transmit Counter (C1) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|X|B|T| DSCP | Block Number| SSID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| |
| MBZ (28 octets) |
| |
| |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: Session-Sender Direct Loss Measurement Probe Packet -
Unauthenticated Mode
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (12 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Transmit Counter (C1) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|X|B|T| DSCP | Block Number| SSID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| MBZ (68 octets) |
. .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| HMAC (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: Session-Sender Direct Loss Measurement Probe Packet -
Authenticated Mode
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Fields are defined as the following:
Sequence Number (32-bit): For each new DLM session, its value starts
at zero and is incremented by one with each transmitted DLM probe
packet. The Sequence Number helps to check the DLM session state as
active or not active, as well as detect probe packet drops.
Transmit Counter (64-bit): The number of packets or octets
transmitted by the Session-Sender in the DLM probe packet. The
counter is always written at the well-known fixed location in the DLM
probe packet. This is an important property for hardware-based
implementation, e.g., for point-to-point links and circuits. Counter
is for the data traffic flow under measurement.
XBT Flags (3-bit): The meanings of the Flag bits are:
X: Extended counter format indicator. Indicates the use of
extended (64-bit) counter values. Initialized to 1 upon creation
(and prior to transmission) of a DLM probe packet. Set to 0 when
the DLM probe packet is transmitted or received over an interface
that writes 32-bit counter values.
B: Octet (byte) count. When set to 1, indicates that the Counter
fields represent octet counts. The octet count applies to all
packets within the DLM scope, and the octet count of a packet
transmitted or received includes the total length of that packet
(but excludes headers, labels, or framing of the channel itself).
When set to 0, indicates that the Counter fields represent packet
counts.
T: Traffic-class-specific measurement indicator. Set to 1 when
the DLM session is scoped to data packets of a particular traffic
class (DSCP value), and 0 otherwise. When set to 1, the DSCP
field of the DLM probe packet indicates the measured traffic
class.
DSCP (6-bit): DSCP of the data traffic flow being measured when T
flag is set.
Block Number (7-bit): The Direct Loss Measurement using Alternate-
Marking Method [RFC8321] requires to collect Block Number of the
counters for the data traffic flow under measurement. To be able to
correlate the transmit and receive counters of the matching Block
Number, the Block Number of the counters carried in the DLM probe
packets.
SSID (16-bit): DLM Sender Session Identifier.
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HMAC: The use of the HMAC field is described in Section 4.4 of
[RFC8762]. HMAC uses its own key and the mechanism to distribute the
HMAC key is outside the scope of this document.
MBZ: Must be Zero. It MUST be all zeroed on the transmission and
MUST be ignored on receipt.
5. Session-Reflector Direct Loss Measurement Probe Packet
The Session-Reflector receives the DLM Session-Sender probe packet
and verifies it. If the DLM probe packet is validated, the Session-
Reflector that supports this specification prepares and transmits the
DLM reply probe packet. In this document, Session-Reflector DLM
reply probe packet formats are defined as shown in Figure 3 and
Figure 4, for unauthenticated and authenticated modes, respectively.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Transmit Counter (C3) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|X|B|T| DSCP | Block Number| SSID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Receive Counter (C2) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Session-Sender Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Session-Sender Counter (C1) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|FLAGS| Ses-DSCP |Ses-Block Num| MBZ (2 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Ses-Sender TTL | MBZ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: Session-Reflector Direct Loss Measurement Probe Packet -
Unauthenticated Mode
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (12 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Transmit Counter (C3) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|X|B|T| DSCP | Block Number| SSID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (4 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Receive Counter (C2) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (8 octets) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Session-Sender Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (12 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Session-Sender Counter (C1) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|FLAGS| Ses-DSCP |Ses-Block Num| MBZ (2 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MBZ (4 octets) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Ses-Sender TTL | |
+-+-+-+-+-+-+-+-+ +
| MBZ (15 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| HMAC (16 octets) |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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Figure 4: Session-Reflector Direct Loss Measurement Probe Packet -
Authenticated Mode
Fields are defined as the following:
Sequence Number (32-bit): This is the exact copy of the Sequence
Number from the received Session-Sender DLM probe packet that allows
Stateless mode of Session-Reflector.
Transmit Counter (64-bit): The number of packets or octets
transmitted by the Session-Reflector in the DLM reply probe packet.
Counter is for the reverse direction data traffic flow under
measurement. The Session-Reflector writes the Transmit Counter at
the same location in the DLM reply probe packet as the Session-Sender
DLM probe packet. This is an important property for hardware-based
implementation.
XBT Flags (3-bit): The XBT Flags for the reverse direction data
traffic flow under measurement set using the same procedure defined
for the Session-Sender DLM probe packet.
DSCP (6-bit): Set for the reverse direction data traffic flow under
measurement using the same procedure defined for the Session-Sender
DLM probe packet.
Block Number (7-bit): Set for the reverse direction data traffic flow
under measurement using the same procedure defined for the Session-
Sender DLM probe packet.
SSID: SSID is the exact copy of the SSID in the received Session-
Sender DLM probe packet.
Receive Counter (64-bit): The number of packets or octets received at
the Session-Reflector. It is written by the Session-Reflector in the
DLM reply probe packet. Counter is for the data traffic flow under
measurement.
Session-Sender Counter (64-bit): This is the exact copy of the
Transmit Counter from the received Session-Sender DLM probe packet.
Session-Sender Sequence Number (32-bit): This is the exact copy of
the Sequence Number from the received Session-Sender DLM probe
packet.
Session-Sender Block Number: This is the exact copy of the Block
Number from the received Session-Sender DLM probe packet.
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Session-Sender FLAGS: This is the exact copy of the XBT Flags from
the received Session-Sender DLM probe packet.
Session-Sender DSCP: This is the exact copy of the DSCP from the
received Session-Sender DLM probe packet.
Session-Sender TTL: The Session-Sender TTL field is one octet long,
and its value is the copy of the TTL field in IPv4 (or Hop Limit in
IPv6) from the received Session-Sender DLM probe packet.
6. Data Loss Calculation
Using the Counters C1, C2, C3 and C4 as per reference topology, from
the nth and (n-1)th DLM probe packets, packet loss and byte loss for
the data traffic flow can be calculated as follows:
Transmit Loss TxL[ n-1, n] = (C1[ n] - C1[ n-1]) - (C2[ n] - C2[
n-1])
Receive Loss RxL[ n-1, n] = (C3[ n] - C3[ n-1]) - (C4[ n] - C4[ n-1])
The Total Transmit and Receive Loss are calculated as follows:
Total Transmit Loss = TxL[ 1, 2] + TxL[ 2, 3] + ...
Total Receive Loss = RxL[ 1, 2] + RxL[ 2, 3] + ...
These values are updated each time a DLM reply probe packet is
received and processed at the Session-Sender, and they represent the
Total Transmit and Total Receive Loss since the DLM session was
initiated. When computing the values TxL[n-1,n] and RxL[n-1,n], the
possibility of counter wrap must be taken into account.
When using Alternate-Marking Method, all Counters used for loss
calculation belongs to the same Block Number, as described in
Section 3.1 of [RFC8321].
7. Optional Extensions
There are currently no optional (TLV) extensions defined for the DLM
probe packets.
8. Integrity Protection and Confidentiality Protection
The integrity protection and confidentiality protection specified in
[RFC8762] also apply to the procedures defined in this document.
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9. Operational Considerations
The operational considerations specified in [RFC8762] also apply to
the procedures defined in this document.
10. Security Considerations
The DLM protocol is intended for deployment in limited domains
[RFC8799]. As such, it assumes that a node involved in DLM protocol
operation has previously verified the integrity of the path and the
identity of the far-end Session-Reflector.
If desired, attacks can be mitigated by performing basic validation
and sanity checks, at the Session-Sender, of the counter fields in
received reply probe packets. The minimal state associated with
these protocols also limits the extent of measurement disruption that
can be caused by a corrupt or invalid probe packet to a single probe
cycle.
The security considerations specified in [RFC8762] and [RFC8972] also
apply to the protocol defined in this document. Specifically, the
message integrity protection using HMAC, as defined in [RFC8762]
Section 4.4, also apply to the procedure described in this document.
11. IANA Considerations
This document has no IANA actions.
12. References
12.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8321] Fioccola, G., Ed., Capello, A., Cociglio, M., Castaldelli,
L., Chen, M., Zheng, L., Mirsky, G., and T. Mizrahi,
"Alternate-Marking Method for Passive and Hybrid
Performance Monitoring", RFC 8321, DOI 10.17487/RFC8321,
January 2018, <https://www.rfc-editor.org/info/rfc8321>.
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[RFC8762] Mirsky, G., Jun, G., Nydell, H., and R. Foote, "Simple
Two-Way Active Measurement Protocol", RFC 8762,
DOI 10.17487/RFC8762, March 2020,
<https://www.rfc-editor.org/info/rfc8762>.
12.2. Informative References
[RFC7680] Almes, G., Kalidindi, S., Zekauskas, M., and A. Morton,
Ed., "A One-Way Loss Metric for IP Performance Metrics
(IPPM)", STD 82, RFC 7680, DOI 10.17487/RFC7680, January
2016, <https://www.rfc-editor.org/info/rfc7680>.
[RFC8799] Carpenter, B. and B. Liu, "Limited Domains and Internet
Protocols", RFC 8799, DOI 10.17487/RFC8799, July 2020,
<https://www.rfc-editor.org/info/rfc8799>.
[RFC8972] Mirsky, G., Min, X., Nydell, H., Foote, R., Masputra, A.,
and E. Ruffini, "Simple Two-Way Active Measurement
Protocol Optional Extensions", RFC 8972,
DOI 10.17487/RFC8972, January 2021,
<https://www.rfc-editor.org/info/rfc8972>.
[ITU-Y1731]
Recommendation ITU-TG.8013/Y.1731:
https://www.itu.int/rec/T-REC-G.8013-201508-I/en, "G.8013/
Y.1731 : Operations, administration and maintenance (OAM)
functions and mechanisms for Ethernet-based networks",
August 2015.
[SRV6-PM-TNSM]
Loreti, P., Mayer, A., Lungaroni, P., Lombardo, F.,
Scarpitta, C., Sidoretti, G., Bracciale, L., Ferrari, M.,
Salsano, S., Abdelsalam, A., Gandhi, R., and C. Filsfils,
IEEE Transactions on Network and Service Management,
"SRv6-PM: Performance Monitoring of SRv6 Networks with a
Cloud-Native Architecture:
https://arxiv.org/pdf/2007.08633.pdf", February 2021.
[SRV6-PM-IEEE]
Loreti, P., Mayer, A., Lungaroni, P., Salsano, S., Gandhi,
R., and C. Filsfils, IEEE International Conference on High
Performance Switching and Routing, "Implementation of
Accurate Per-Flow Packet Loss Monitoring in Segment
Routing over IPv6 Networks:
https://arxiv.org/pdf/2004.11414.pdf", May 2020.
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Internet-Draft Simple Direct Loss Measurement Procedure February 2022
Acknowledgments
The authors would like to thank Greg Mirsky, Tianran Zhou, Gyan
Mishra, Zhenqiang Li, Reshad Rahman, Cheng Li, and Yali Wang for the
comments on Direct Loss Measurement. The authors would like to thank
Pierpaolo Loreti and the team for the Open Source implementation of
SRv6-PM Loss Monitoring and its publications in [SRV6-PM-TNSM] and
[SRV6-PM-IEEE]. The authors would like to acknowledge the earlier
work on the loss measurement using TWAMP described in draft-xiao-
ippm-twamp-ext-direct-loss.
Authors' Addresses
Rakesh Gandhi (editor)
Cisco Systems, Inc.
Canada
Email: rgandhi@cisco.com
Clarence Filsfils
Cisco Systems, Inc.
Email: cfilsfil@cisco.com
Daniel Voyer
Bell Canada
Email: daniel.voyer@bell.ca
Mach(Guoyi) Chen
Huawei
Email: mach.chen@huawei.com
Bart Janssens
Colt
Email: Bart.Janssens@colt.net
Stefano Salsano
Universita di Roma "Tor Vergata"
Italy
Gandhi, et al. Expires 8 August 2022 [Page 15]
Internet-Draft Simple Direct Loss Measurement Procedure February 2022
Email: stefano.salsano@uniroma2.it
Gandhi, et al. Expires 8 August 2022 [Page 16]