Label Switched Path (LSP) Ping/Trace over MPLS Network using Entropy Labels (EL)
draft-akiya-mpls-entropy-lsp-ping-00
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft whose latest revision state is "Replaced".
|
|
|---|---|---|---|
| Authors | Nobo Akiya , George Swallow , Carlos Pignataro | ||
| Last updated | 2013-11-01 (Latest revision 2013-10-21) | ||
| Replaced by | draft-ietf-mpls-entropy-lsp-ping, RFC 8012 | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Formats | |||
| Additional resources | Mailing list discussion | ||
| Stream | WG state | Candidate for WG Adoption | |
| Document shepherd | Loa Andersson | ||
| IESG | IESG state | I-D Exists | |
| Consensus boilerplate | Unknown | ||
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
draft-akiya-mpls-entropy-lsp-ping-00
Internet Engineering Task Force N. Akiya
Internet-Draft G. Swallow
Updates: 4379,6790 (if approved) C. Pignataro
Intended status: Standards Track Cisco Systems
Expires: April 24, 2014 October 21, 2013
Label Switched Path (LSP) Ping/Trace over MPLS Network
using Entropy Labels (EL)
draft-akiya-mpls-entropy-lsp-ping-00
Abstract
The Multiprotocol Label Switching (MPLS) Label Switched Path (LSP)
Ping and Traceroute are used to exercise specific paths of Equal Cost
Multipath (ECMP). This ability has been lost on some scenarios which
makes use of [RFC6790]: Entropy Labels (EL).
This document extends the MPLS LSP Ping and Traceroute mechanisms to
restore the ability of exercising specific paths of ECMP over LSP
which make use of Entropy Label. This document updates [RFC4379] and
[RFC6790].
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 RFC 2119 [RFC2119].
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
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
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 April 24, 2014.
Copyright Notice
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Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://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 and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Multipath Type 9 . . . . . . . . . . . . . . . . . . . . . . 5
4. Initiating LSR Procedures . . . . . . . . . . . . . . . . . . 6
5. Responder LSR Procedures . . . . . . . . . . . . . . . . . . 7
5.1. IP Based Load Balancer & Not Imposing ELI/EL . . . . . . 7
5.2. IP Based Load Balancer & Imposing ELI/EL . . . . . . . . 8
5.3. Label Based Load Balancer & Not Imposing ELI/EL . . . . . 8
5.4. Label Based Load Balancer & Imposing ELI/EL . . . . . . . 9
5.5. FAT MS-PW Stitching LSR . . . . . . . . . . . . . . . . . 9
6. Entropy Label FEC . . . . . . . . . . . . . . . . . . . . . . 10
7. DS Flags: L and E . . . . . . . . . . . . . . . . . . . . . . 10
8. New Multipath Information Type: 10 . . . . . . . . . . . . . 11
9. Unsupported Cases . . . . . . . . . . . . . . . . . . . . . . 13
10. Security Considerations . . . . . . . . . . . . . . . . . . . 13
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
11.1. DS Flags . . . . . . . . . . . . . . . . . . . . . . . . 13
11.2. Multipath Information Types . . . . . . . . . . . . . . 13
11.3. Entropy Label FEC . . . . . . . . . . . . . . . . . . . 13
12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
13. Contributing Authors . . . . . . . . . . . . . . . . . . . . 14
14. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
14.1. Normative References . . . . . . . . . . . . . . . . . . 14
14.2. Informative References . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
1. Introduction
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Section 3.3.1 of [RFC4379] specifies multipath information encoding
which can be used by LSP Ping initiator to trace and validate all
ECMP paths between ingress and egress. These encodings are
sufficient when all the LSRs along the path(s), between ingress and
egress, consider same set of "keys" as input for load balancing
algorithm: all IP based or all label based.
With introduction of [RFC6790], it is quite normal to see set of LSRs
performing load balancing based on EL/ELI while others still follow
the traditional way (IP based). This results in LSP Ping initiator
not be able to trace and validate all ECMP paths in following
scenarios:
o One or more transit LSRs along ELI/EL imposed LSP do not perform
ECMP load balancing based on EL (hashes based on "keys" including
IP destination address). This scenario is not only possible but
quite common due transit LSRs not implementing [RFC6790] or
transit LSRs implementing [RFC6790] but not implementing suggested
transit LSR behavior in Section 4.3 of [RFC6790].
o Two or more LSPs stitched together with at least one LSP being ELI
/EL imposing LSP. Such scenarios are described in
[I-D.ravisingh-mpls-el-for-seamless-mpls].
These scenarios will be quite common because every deployment of
[RFC6790] will invariably end up with nodes that support ELI/EL and
nodes that do not. There will typically be areas that support ELI/EL
and areas that do not.
As pointed out in [RFC6790] the procedures of [RFC4379] with respect
to multipath information type {9} are incomplete. However [RFC6790]
does not actually update [RFC4379]. Further the specific EL location
is not clearly defined, particularly in the case of FAT Pseudowires
[RFC6391]. Herein is defined a new FEC Stack sub-TLV for the Entropy
Label. Section 3 of this document updates the procedures for
multipath information type {9}.
2. Overview
[RFC4379] describes LSP traceroute as an operation performed through
initiating LSR sending LSP Ping packet (LSP echo request) with
incrementing TTL, starting with TTL of one. Initiating LSR discovers
and exercises ECMP by obtaining multipath information from each
transit LSR and using specific destination IP address or specific
entropy label.
LSP Ping initiating LSR sends LSP echo request with multipath
information. This multipath information is described in DSMAP/DDMAP
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TLV of echo request, and can contain set of IP addresses or set of
labels today. Multipath information types {2, 4, 8} carry set of IP
addresses and multipath information type {9} carries set of labels.
Responder LSR (receiver of LSP echo request) is to determine subset
of initiator specified multipath information which load balances to
each downstream (outgoing interface). Responder LSR sends LSP echo
reply with resulting multipath information per downstream (outgoing
interface) back to the initiating LSR. Initiating LSR is then able
to use specific IP destination address or specific label to exercise
specific ECMP path on the responder LSR.
Current behavior is problematic in following scenarios:
o Initiating LSR sends IP multipath information, but responder LSR
load balances on labels.
o Initiating LSR sends label multipath information, but responder
LSR load balances on IP addresses.
o Initiating LSR sends any of existing multipath information to ELI/
EL imposing LSR, but initiating LSR can only continue to discover
and exercise specific path of ECMP if ELI/EL imposing LSR responds
with both IP addresses and associated EL corresponding to each IP
address. This is because:
* ELI/EL imposing LSR that is a stitching point will load balance
based on IP address.
* Downstream LSR(s) of ELI/EL imposing LSR may load balance based
on ELs.
o Initiating LSR sends any of existing multipath information to ELI/
EL imposing LSR, but initiating LSR can only continue to discover
and exercise specific path of ECMP if ELI/EL imposing LSR responds
with both labels and associated EL corresponding to label. This
is because:
* ELI/EL imposing LSR that is a stitching point will load balance
based on EL from previous LSP and imposes new EL.
* Downstream LSR(s) of ELI/EL imposing LSR may load balance based
on new ELs.
The above scenarios point to how the existing multipath information
is insufficient when LSP traceroute is operated on an LSP with
Entropy Labels described by [RFC6790]. Therefore, this document
defines a multipath information type to be used in the DSMAP/DDMAP of
LSP echo request/reply packets in Section 8.
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In addition, responder LSR can reply with empty multipath information
if no IP address set or label set from received multipath information
matched load balancing to a downstream. Empty return is also
possible if initiating LSR sends multipath information of one type,
IP address or label, but responder LSR load balances on the other
type. To disambiguate between the two results, this document
introduces new flags in the DSMAP/DDMAP TLV to allow responder LSR to
describe the load balance technique being used.
It is required that all LSRs along the LSP understand new flags as
well as new multipath information type. It is also required that
initiating LSR can select both IP destination address and label to
use on transmitting LSP echo request packets. Two additional DS
Flags are defined for the DSMAP and DDMAP TLVs in Section 7.
3. Multipath Type 9
[RFC4379] defined multipath type {9} for tracing of LSPs where label
based load-balancing is used. However, as pointed out in [RFC6790],
the procedures for using this type are incomplete. First, the
specific location of the label was not defined. What was assumed,
but not spelled out, was that the presence of multipath type {9}
meant the responder should act as if the payload of the received
packet were non-IP and that the bottom-of-stack label should be
replaced by the values indicated by multipath type {9} to determine
their respective out-going interfaces.
Further, with the introduction of [RFC6790], entropy labels may now
appear anywhere in a label stack.
This section defines to which labels multipath type {9} can apply.
Additionally it defines procedures for tracing pseudowires and flow-
aware pseudowires. These procedures pertain to the use of multipath
information type {9} as well as type {10}.
Section 6 defines a new FEC-Stack sub-TLV to indicate and entropy
label. Multipath type {9} applies exclusively to this sub-TLV. Any
LSP Ping message containing a DD-MAP or DS-MAP with multipath type
{9} MUST include an EL_FEC at the bottom of the FEC-Stack.
When an MPLS echo request message is received containing a FEC-Stack
with an EL-FEC at the bottom of the FEC stack and is not preceded by
an entropy label, the responder must behave (for load balancing
purposes) as if the first word of the message were a Pseudowire
Control Word.
In order to trace a non-FAT pseudowire, instead of including the
appropriate PW-FEC in the FEC-Stack, an EL-FEC is included. Tracing
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in this way will cause compliant routers to return the proper
outgoing interface. Note that this procedure only traces to the end
of the MPLS transport LSP (e.g. LDP and/or RSVP). To actually verify
the PW-FEC or in the case of a MS-PW, to determine the next
pseudowire label value, the initiator MUST repeat that step of the
trace, (i.e., repeating the TTL value used) but with the FEC-Stack
modified to contain the appropriate PW-FEC.
In order to trace a FAT pseudowire, the initiator includes an EL-FEC
at the bottom of the FEC-Stack and pushes the appropriate PW-FEC onto
the FEC-Stack.
4. Initiating LSR Procedures
In order to facilitate the flow of the following text we speak in
terms of a boolean called EL_LSP maintained by the initiating LSR.
This value controls the multipath information type to be used in
transmitted echo request packets. When the initiating LSR is
transmitting an echo request packet with DSMAP/DDMAP with a non-zero
multipath information type, then EL_LSP boolean MUST be consulted to
determine the multipath information type to use.
In addition to procedures described in [RFC4379] as updated by
Section 3 and [RFC6424], initiating LSR MUST operate with following
procedures.
o When initiating LSR is IP based load balancer (not imposing ELI/
EL), initialize EL_LSP=False.
o When initiating LSR imposes ELI/EL, initialize EL_LSP=True.
o When initiating LSR is transmitting non-zero multipath information
type:
If (EL_LSP) initiating LSR MUST use multipath information type
{10}.
Else initiating LSR MUST use multipath information type {2, 4,
8, 9}.
o When initiating LSR is transmitting multipath information type
{10}, both "IP Multipath Information" and "Label Multipath
Information" MUST be included, and "IP Associated Label Multipath
Information" MUST be omitted (NULL).
o When initiating LSR receives echo reply with {L=0, E=1} in DS
flags with valid contents, set EL_LSP=True.
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In following conditions, initiating LSR may have lost the ability to
exercise specific ECMP paths. Initiating LSR MAY continue with "best
effort".
o Received echo reply contains empty multipath information.
o Received echo reply contains {L=0, E=<any>} DS flags, but does not
contain IP multipath information.
o Received echo reply contains {L=1, E=<any>} DS flags, but does not
contain label multipath information.
o Received echo reply contains {L=<any>, E=1} DS flags, but does not
contain associated label multipath information.
o IP multipath information types {2, 4, 8} sent, and received echo
reply with {L=1, E=0} in DS flags.
o Multipath information type {10} sent, and received echo reply with
multipath information type other than {10}.
5. Responder LSR Procedures
Common Procedures: Responder LSR receiving LSP echo request packet
with multipath information type {10} MUST validate following
contents. Any deviation MUST result in responder LSR to consider the
packet as malformed and return code 1 (Malformed echo request
received) in LSP echo reply packet.
o IP multipath information MUST be included.
o Label multipath information MUST be included.
o IP associated label multipath information MUST be omitted (NULL).
Following subsections describe expected responder LSR procedures when
echo reply is to include DSMAP/DDMAP TLVs, based on local load
balance technique being employed. In case responder LSR performs
deviating load balance techniques per downstream basis, appropriate
procedures matching to each downstream load balance technique MUST be
operated.
5.1. IP Based Load Balancer & Not Imposing ELI/EL
o Responder MUST set {L=0, E=0} in DS flags.
o If multipath information type {2, 4, 8} is received, responder
MUST comply with [RFC4379]/[RFC6424].
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o If multipath information type {9} is received, responder MUST
reply with multipath type {0}.
o If multipath information type {10} is received, responder MUST
reply with multipath information type {10}. "Label Multipath
Information" and "Associated Label Multipath Information" sections
MUST be omitted (NULL). If no matching IP address is found, then
"IPMultipathType" field MUST be set to multipath information type
{0} and "IP Multipath Information" section MUST also be omitted
(NULL). If at least one matching IP address is found, then
"IPMultipathType" field MUST be set to appropriate multipath
information type {2, 4, 8} and "IP Multipath Information" section
MUST be included.
5.2. IP Based Load Balancer & Imposing ELI/EL
o Responder MUST set {L=0, E=1} in DS flags.
o If multipath information type {9} is received, responder MUST
reply with multipath type {0}.
o If multipath type {2, 4, 8, 10} is received, responder MUST
respond with multipath type {10}. "Label Multipath Information"
section MUST be omitted (NULL). IP address set specified in
received IP multipath information MUST be used to determine the
returning IP/Label pairs. If received multipath information type
was {10}, received "Label Multipath Information" sections MUST NOT
be used to determine the associated label portion of returning IP/
Label pairs. If no matching IP address is found, then
"IPMultipathType" field MUST be set to multipath information type
{0} and "IP Multipath Information" section MUST be omitted (NULL).
In addition, "Assoc Label Multipath Length" MUST be set to 0, and
"Associated Label Multipath Information" section MUST also be
omitted (NULL). If at least one matching IP address is found,
then "IPMultipathType" field MUST be set to appropriate multipath
information type {2, 4, 8} and "IP Multipath Information" section
MUST be included. In addition, "Associated Label Multipath
Information" section MUST be populated with list of labels
corresponding to each IP address specified in "IP Multipath
Information" section. "Assoc Label Multipath Length" MUST be set
to appropriate value.
5.3. Label Based Load Balancer & Not Imposing ELI/EL
o Responder MUST set {L=1, E=0} in DS flags.
o If multipath information type {2, 4, 8} is received, responder
MUST reply with multipath type {0}.
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o If multipath information type {9} is received, responder MUST
comply with [RFC4379] /[RFC6424] as updated by Section 3.
o If multipath information type {10} is received, responder MUST
reply with multipath information type {10}. "IP Multipath
Information" and "Associated Label Multipath Information" sections
MUST be omitted (NULL). If no matching label is found, then
"LbMultipathType" field MUST be set to multipath information type
{0} and "Label Multipath Information" section MUST also be omitted
(NULL). If at least one matching label is found, then
"LbMultipathType" field MUST be set to appropriate multipath
information type {9} and "Label Multipath Information" section
MUST be included.
5.4. Label Based Load Balancer & Imposing ELI/EL
o Responder MUST set {L=1, E=1} in DS flags.
o If multipath information type {2, 4, 8} is received, responder
MUST reply with multipath type {0}.
o If multipath type {9, 10} is received, responder MUST respond with
multipath type {10}. "IP Multipath Information" section MUST be
omitted (NULL). Label set specified in received label multipath
information MUST be used to determine the returning Label/Label
pairs. If received multipath information type was {10}, received
"Label Multipath Information" sections MUST NOT be used to
determine the associated label portion of returning Label/Label
pairs. If no matching label is found, then "LbMultipathType"
field MUST be set to multipath information type {0} and "Label
Multipath Information" section MUST be omitted (NULL). In
addition, "Assoc Label Multipath Length" MUST be set to 0, and
"Associated Label Multipath Information" section MUST also be
omitted (NULL). If at least one matching label is found, then
"LbMultipathType" field MUST be set to appropriate multipath
information type {9} and "Label Multipath Information" section
MUST be included. In addition, "Associated Label Multipath
Information" section MUST be populated with list of labels
corresponding to each label specified in "Label Multipath
Information" section. "Assoc Label Multipath Length" MUST be set
to appropriate value.
5.5. FAT MS-PW Stitching LSR
MS-PW stitching LSR that xconnects flow-aware pseudowires behaves in
one of two ways:
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o Load balances on previous flow label, and carries over same flow
label. For this case, stitching LSR is to behave as procedures
described in Section 5.3.
o Load balances on previous flow label, and replaces flow label with
newly computed. For this case, stitching LSR is to behave as
procedures described in Section 5.4.
6. Entropy Label FEC
Entropy Label Indicator (ELI) is a reserved label that has no
explicit FEC associated, and has label value 7 assigned from the
reserved range. Use Nil FEC as Target FEC Stack sub-TLV to account
for ELI in a Target FEC Stack TLV.
Entropy Label (EL) is a special purpose label with label value being
discretionary (i.e. label value may not be from the reserved range).
For LSP verification mechanics to perform its purpose, it is
necessary for a Target FEC Stack sub-TLV to clearly describe EL,
particularly in the scenario where label stack does not carry ELI
(ex: FAT-PW [RFC6391]). Therefore, this document defines a EL FEC to
allow a Target FEC Stack sub-TLV to be added to the Target FEC Stack
to account for EL.
The Length is 4. Labels are 20-bit values treated as numbers.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label | MBZ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Label is the actual label value inserted in the label stack; the MBZ
fields MUST be zero when sent and ignored on receipt.
7. DS Flags: L and E
Two flags, L and E, are added in DS Flags field of the DSMAP/DDMAP
TLVs. Both flags MUST NOT be set in echo request packets when
sending, and ignored when received. Zero, one or both new flags MUST
be set in echo reply packets.
DS Flags
--------
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
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| MBZ |L|E|I|N|
+-+-+-+-+-+-+-+-+
Flag Name and Meaning
---- ----------------
L Label based load balance indicator
This flag MUST be set to zero in the echo request. LSR
which performs load balancing on a label MUST set this
flag in the echo reply. LSR which performs load
balancing on IP MUST NOT set this flag in the echo
reply.
E ELI/EL imposer indicator
This flag MUST be set to zero in the echo request. LSR
which imposes ELI/EL MUST set this flag in the echo
reply. LSR which does not impose ELI/EL MUST NOT set
this flag in the echo reply.
Two flags result in four load balancing techniques which echo reply
generating LSR can indicate:
o {L=0, E=0} LSR load balances based on IP and does not impose ELI/
EL.
o {L=0, E=1} LSR load balances based on IP and imposes ELI/EL.
o {L=1, E=0} LSR load balances based on label and does not impose
ELI/EL.
o {L=1, E=1} LSR load balances based on label and imposes ELI/EL.
8. New Multipath Information Type: 10
One new multipath information type is added to be used in DSMAP/DDMAP
TLVs. New multipath type has value of 10.
Key Type Multipath Information
--- ---------------- ---------------------
10 IP and label set IP addresses and label prefixes
Multipath type 10 is comprised of three sections. One section to
describe IP address set. One section to describe label set. One
section to describe another label set which associates to either IP
address set or label set specified in the other section.
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Multipath information type 10 has following format:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|IPMultipathType| Reserved(MBZ) | IP Multipath Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ ~
| (IP Multipath Information) |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|LbMultipathType| Reserved(MBZ) | Label Multipath Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ ~
| (Label Multipath Information) |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved(MBZ) | Assoc Label Multipath Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ ~
| (Associated Label Multipath Information) |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o IP Multipath Information
This section reuses IP multipath information from [RFC4379].
Specifically, values {0, 2, 4, 8} can be used.
o Label Multipath Information
This section reuses label multipath information from [RFC4379].
Specifically, values {0, 9} can be used.
o Associated Label Multipath Information
"Assoc Label Multipath Length" is a 16 bit field of multipath
information which indicates length in octets of the associated
label multipath information.
"Associated Label Multipath Information" is a list of labels
with each label described in 24 bits. This section MUST be
omitted (NULL) in an MPLS Echo Request message. A midpoint
which imposes ELI/EL labels SHOULD include "Assoc Label
Multipath Information" in its MPLS Echo Reply message, along
with either "IP Multipath Information" or "Label Multipath
Information". Each specified associated label described in
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this section maps to specific IP address OR label described in
the "IP Multipath Information" section or "Label Multipath
Information" section. For example, if 3 IP addresses are
specified in the "IP Multipath Information" section, then there
MUST be 3 labels described in this section. First label maps
to the lowest IP address specified, second label maps to the
second lowest IP address specified and third label maps to the
third lowest IP address specified.
9. Unsupported Cases
There are couple of scenarios where LSP path tracing mechanics are
not supported in this draft revision.
o When one or more LSP transit node(s) performs label based load
balancing on a label that is not bottom-of-stack label when
Entropy Label Indicator is not included.
o When one or more LSP transit node(s) performs label based load
balancing on a label other than Entropy Label when Entropy Label
Indicator and Entropy Label pair is included.
10. Security Considerations
Beyond those specified in [RFC4379], [RFC6424] and [RFC6790], there
are no further security measured required.
11. IANA Considerations
11.1. DS Flags
DS flags ... not maintained by IANA. Should it be?
11.2. Multipath Information Types
Multipath information types ... not maintained by IANA. Should it
be?
11.3. Entropy Label FEC
IANA is requested to assign a new sub-TLV from the "Sub-TLVs for TLV
Types 1 and 16" section from "TLVs" sub-registry within the "Multi-
Protocol Label Switching (MPLS) Label Switched Paths (LSPs) Ping
Parameters" registry.
Following value appears to be next available sub-TLV value.
Requesting IANA to allow specified value as early allocation.
Akiya, et al. Expires April 24, 2014 [Page 13]
Internet-Draft LSP Ping over Entropy October 2013
Value Meaning Reference
----- ------- ---------
26 Entropy Label FEC this document
12. Acknowledgements
TBD
13. Contributing Authors
Nagendra Kumar
Cisco Systems
Email: naikumar@cisco.com
14. References
14.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC4379] Kompella, K. and G. Swallow, "Detecting Multi-Protocol
Label Switched (MPLS) Data Plane Failures", RFC 4379,
February 2006.
[RFC6790] Kompella, K., Drake, J., Amante, S., Henderickx, W., and
L. Yong, "The Use of Entropy Labels in MPLS Forwarding",
RFC 6790, November 2012.
14.2. Informative References
[I-D.ravisingh-mpls-el-for-seamless-mpls]
Singh, R., Shen, Y., and J. Drake, "Entropy label for
seamless MPLS", draft-ravisingh-mpls-el-for-seamless-
mpls-00 (work in progress), February 2013.
[RFC6391] Bryant, S., Filsfils, C., Drafz, U., Kompella, V., Regan,
J., and S. Amante, "Flow-Aware Transport of Pseudowires
over an MPLS Packet Switched Network", RFC 6391, November
2011.
[RFC6424] Bahadur, N., Kompella, K., and G. Swallow, "Mechanism for
Performing Label Switched Path Ping (LSP Ping) over MPLS
Tunnels", RFC 6424, November 2011.
Authors' Addresses
Akiya, et al. Expires April 24, 2014 [Page 14]
Internet-Draft LSP Ping over Entropy October 2013
Nobo Akiya
Cisco Systems
Email: nobo@cisco.com
George Swallow
Cisco Systems
Email: swallow@cisco.com
Carlos Pignataro
Cisco Systems
Email: cpignata@cisco.com
Akiya, et al. Expires April 24, 2014 [Page 15]