rfc9570.original   rfc9570.txt 
MPLS WG K. Kompella Internet Engineering Task Force (IETF) K. Kompella
Internet-Draft R. Bonica Request for Comments: 9570 R. Bonica
Updates: 8029 (if approved) Juniper Networks Updates: 8029 Juniper Networks
Intended status: Standards Track G. Mirsky, Ed. Category: Standards Track G. Mirsky, Ed.
Expires: 2 September 2024 Ericsson ISSN: 2070-1721 Ericsson
1 March 2024 May 2024
Deprecating the Use of Router Alert in LSP Ping Deprecating the Use of Router Alert in LSP Ping
draft-ietf-mpls-lspping-norao-08
Abstract Abstract
The MPLS echo request and MPLS echo response messages, defined in RFC The MPLS echo request and MPLS echo response messages, defined in RFC
8029 "Detecting Multiprotocol Label Switched (MPLS) Data-Plane 8029, "Detecting Multiprotocol Label Switched (MPLS) Data-Plane
Failures" (usually referred to as LSP ping messages), are Failures" (usually referred to as LSP ping), are encapsulated in IP
encapsulated in IP whose headers include a Router Alert Option (RAO). packets with headers that include a Router Alert Option (RAO). In
In actual deployments, the RAO was neither required nor used. actual deployments, the RAO was neither required nor used.
Furthermore, RFC 6398 identifies security vulnerabilities associated Furthermore, RFC 6398 identifies security vulnerabilities associated
with the RAO in non-controlled environments, e.g., the case of using with the RAO in non-controlled environments, e.g., the case of using
the MPLS echo request/reply as inter-area Operations, Administration, the MPLS echo request/reply as inter-area Operations, Administration,
and Maintenance (OAM), and recommends against its use outside of and Maintenance (OAM), and recommends against its use outside of
controlled environments. controlled environments.
Therefore, this document retires the RAO for MPLS OAM and updates RFC Therefore, this document retires the RAO for MPLS OAM and updates RFC
8029 to remove the RAO from LSP ping message encapsulations. 8029 to remove the RAO from LSP ping message encapsulations.
Furthermore, this document explains why RFC 7506 has been Furthermore, this document explains why RFC 7506 has been
reclassified as Historic. reclassified as Historic.
Also, the use of an IPv6 loopback address (::1/128) as the IPv6 Also, this document recommends the use of an IPv6 loopback address
destination address for an MPLS echo request message is RECOMMENDED. (::1/128) as the IPv6 destination address for an MPLS echo request
message.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This is an Internet Standards Track document.
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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Internet-Drafts are draft documents valid for a maximum of six months This document is a product of the Internet Engineering Task Force
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time. It is inappropriate to use Internet-Drafts as reference received public review and has been approved for publication by the
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Internet Standards is available in Section 2 of RFC 7841.
This Internet-Draft will expire on 2 September 2024. Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc9570.
Copyright Notice Copyright Notice
Copyright (c) 2024 IETF Trust and the persons identified as the Copyright (c) 2024 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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Table of Contents Table of Contents
1. Note for the RFC Editor . . . . . . . . . . . . . . . . . . . 2 1. Introduction
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Requirements Language
2.1. Requirements Language . . . . . . . . . . . . . . . . . . 3 2. Router Alert for LSP Ping (RFC 8029)
3. Router Alert for LSP Ping (RFC 8029) . . . . . . . . . . . . 3 2.1. MPLS Echo Request
3.1. MPLS Echo Request . . . . . . . . . . . . . . . . . . . . 4 2.2. MPLS Echo Reply
3.2. MPLS Echo Reply . . . . . . . . . . . . . . . . . . . . . 4 3. Reclassification of RFC 7506 as Historic
4. Reclassification of RFC 7506 as Historic . . . . . . . . . . 5 4. Update to RFC 8029
5. Update to RFC 8029 . . . . . . . . . . . . . . . . . . . . . 5 5. Backwards Compatibility
6. Backwards Compatibility . . . . . . . . . . . . . . . . . . . 7 6. IANA Considerations
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 7. Security Considerations
8. Security Considerations . . . . . . . . . . . . . . . . . . . 8 8. References
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 8 8.1. Normative References
10. Normative References . . . . . . . . . . . . . . . . . . . . 8 8.2. Informative References
11. Informational References . . . . . . . . . . . . . . . . . . 9 Acknowledgments
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10 Authors' Addresses
1. Note for the RFC Editor
Per IESG decision, this document MUST be processed only after the
status of RFC 7506 is changed to Historical. This note must be
removed before the publication.
2. Introduction 1. Introduction
RFC 8029 - "Detecting Multiprotocol Label Switched (MPLS) Data-Plane "Detecting Multiprotocol Label Switched (MPLS) Data-Plane Failures"
Failures" (usually referred to as LSP Ping) [RFC8029] detects data- (usually referred to as LSP ping) [RFC8029] detects data plane
plane failures in MPLS Label Switched Paths (LSPs). It can operate failures in MPLS Label Switched Paths (LSPs). It can operate in
in "ping mode" or "traceroute mode". When operating in ping mode, it "ping mode" or "traceroute mode." When operating in ping mode, it
checks LSP connectivity. When operating in traceroute mode, it can checks LSP connectivity. When operating in traceroute mode, it can
trace an LSP and localize failures to a particular node along an LSP. trace an LSP and localize failures to a particular node along an LSP.
The reader is assumed be familiar with [RFC8029] and its terminology. The reader is assumed be familiar with [RFC8029] and its terminology.
LSP ping defines a probe message called the "MPLS echo request". It LSP ping defines a probe message called the "MPLS echo request." It
also defines a response message called the "MPLS echo reply". Both also defines a response message called the "MPLS echo reply." Both
messages are encapsulated in UDP and IP. The MPLS echo request messages are encapsulated in UDP and IP. The MPLS echo request
message is further encapsulated in an MPLS label stack, except when message is further encapsulated in an MPLS label stack, except when
all of the Forwarding Equivalency Classes in the stack correspond to all of the Forwarding Equivalency Classes in the stack correspond to
Implicit Null labels. Implicit Null labels.
When operating in ping mode, LSP ping sends a single MPLS echo When operating in ping mode, LSP ping sends a single MPLS echo
request message, with the MPLS TTL set to 255. This message is request message, with the MPLS TTL set to 255. This message is
intended to reach the egress Label Switching Router (LSR). When intended to reach the egress Label Switching Router (LSR). When
operating in traceroute mode, MPLS ping sends multiple MPLS echo operating in traceroute mode, MPLS ping sends multiple MPLS echo
request messages as defined in Section 4.3 of [RFC8029]. It request messages as defined in Section 4.3 of [RFC8029]. It
manipulates the MPLS TTL so that the first message expires on the manipulates the MPLS TTL so that the first message expires on the
first LSR along the path and subsequent messages expire on subsequent first LSR along the path, and subsequent messages expire on
LSRs. subsequent LSRs.
According to [RFC8029], the IP header that encapsulates an MPLS echo According to [RFC8029], the IP header that encapsulates an MPLS echo
request message must include a Router Alert Option (RAO). request message must include a Router Alert Option (RAO).
Furthermore, [RFC8029] also says that the IP header that encapsulates Furthermore, [RFC8029] also says that the IP header that encapsulates
an MPLS echo reply message must include an RAO if the value of the an MPLS echo reply message must include an RAO if the value of the
Reply Mode in the corresponding MPLS echo request message is "Reply Reply Mode in the corresponding MPLS echo request message is "Reply
via an IPv4/IPv6 UDP packet with Router Alert". This document via an IPv4/IPv6 UDP packet with Router Alert." This document
explains why RAO was not needed in both cases. Furthermore, explains why an RAO was not needed in both cases. Furthermore,
[RFC6398] identifies security vulnerabilities associated with the RAO [RFC6398] identifies security vulnerabilities associated with the RAO
in non-controlled environments, e.g., the case of using the MPLS echo in non-controlled environments, e.g., the case of using the MPLS echo
request/reply as inter-domain OAM over the public Internet, and request/reply as inter-domain OAM over the public Internet, and
recommends against its use outside of controlled environments, e.g., recommends against its use outside of controlled environments, e.g.,
outside a single administrative domain. outside a single administrative domain.
Therefore, this document updates RFC 8029 [RFC8029] to retire the RAO Therefore, this document updates RFC 8029 [RFC8029] to retire the RAO
from both LSP ping message encapsulations and explains why RFC 7506 from both LSP ping message encapsulations and explains why RFC 7506
[RFC7506] has been reclassified as Historic. [RFC7506] has been reclassified as Historic.
2.1. Requirements Language 1.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP "OPTIONAL" in this document are to be interpreted as described in
14 [RFC2119] [RFC8174] when, and only when, they appear in all BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here. capitals, as shown here.
3. Router Alert for LSP Ping (RFC 8029) 2. Router Alert for LSP Ping (RFC 8029)
3.1. MPLS Echo Request
2.1. MPLS Echo Request
While the MPLS echo request message must traverse every node in the While the MPLS echo request message must traverse every node in the
LSP under test, it must not traverse any other node. Specifically, LSP under test, it must not traverse any other nodes. Specifically,
the message must not be forwarded beyond the egress Label Switching the message must not be forwarded beyond the egress Label Switching
Router (LSR). To achieve this, a set of the mechanisms that are used Router (LSR). To achieve this, a set of the mechanisms that are used
concurrently to prevent leaking MPLS echo request messages has been concurrently to prevent leaking MPLS echo request messages has been
defined in [RFC8029]: defined in [RFC8029]:
1. When the MPLS echo request message is encapsulated in IPv4, the 1. When the MPLS echo request message is encapsulated in IPv4, the
IPv4 destination address must be chosen from the subnet 127/8. IPv4 destination address must be chosen from the subnet 127/8.
When the MPLS echo request message is encapsulated in IPv6, the When the MPLS echo request message is encapsulated in IPv6, the
IPv6 destination address must be chosen from the subnet IPv6 destination address must be chosen from the subnet
0:0:0:0:0:FFFF:7F00:0/104. 0:0:0:0:0:FFFF:7F00:0/104.
2. When the MPLS echo request message is encapsulated in IPv4, the 2. When the MPLS echo request message is encapsulated in IPv4, the
IPv4 TTL must be equal to 1. When the MPLS echo request message IPv4 TTL must be equal to 1. When the MPLS echo request message
is encapsulated in IPv6, the IPv6 Hop Limit must be equal to 1. is encapsulated in IPv6, the IPv6 Hop Limit must be equal to 1.
For further information on the encoding of the TTL/Hop Limit in For further information on the encoding of the TTL / Hop Limit in
an MPLS echo request message, see Section 4.3 of [RFC8029]. an MPLS echo request message, see Section 4.3 of [RFC8029].
3. When the MPLS echo request message is encapsulated in IPv4, the 3. When the MPLS echo request message is encapsulated in IPv4, the
IPv4 header must include an RAO with the option value set to IPv4 header must include an RAO with the option value set to
"Router shall examine packet" [RFC2113]. When the MPLS echo "Router shall examine packet" [RFC2113]. When the MPLS echo
request message is encapsulated in IPv6, the IPv6 header chain request message is encapsulated in IPv6, the IPv6 header chain
must include a Hop-by-hop extension header and the Hop-by-hop must include a hop-by-hop extension header and the hop-by-hop
extension header must include an RAO with the option value set to extension header must include an RAO with the option value set to
MPLS OAM [RFC7506]. MPLS OAM [RFC7506].
Currently, all of these are required. However, any one is sufficient Currently, all of these are required. However, any one is sufficient
to prevent forwarding the packet beyond the egress LSR. to prevent forwarding the packet beyond the egress LSR.
Therefore, this document updates RFC 8029 [RFC8029] in that Therefore, this document updates RFC 8029 [RFC8029] in that
Requirement 3 is removed. Requirement 3 is removed.
No implementation that relies on the RAO to prevent packets from No implementation that relies on the RAO to prevent packets from
being forwarded beyond the egress LSR have been reported to the MPLS being forwarded beyond the egress LSR has been reported to the MPLS
working group. Working Group.
3.2. MPLS Echo Reply 2.2. MPLS Echo Reply
An LSP ping replies to the MPLS echo request message with an MPLS An LSP ping replies to the MPLS echo request message with an MPLS
echo reply message. Four reply modes are defined in [RFC8029]: echo reply message. Four reply modes are defined in [RFC8029]:
1. Do not reply 1. Do not reply
2. Reply via an IPv4/IPv6 UDP packet 2. Reply via an IPv4/IPv6 UDP packet
3. Reply via an IPv4/IPv6 UDP packet with Router Alert 3. Reply via an IPv4/IPv6 UDP packet with Router Alert
4. Reply via application-level control channel 4. Reply via application-level control channel
The rationale for mode 3 is questionable, if not wholly misguided. The rationale for mode 3 is questionable, if not wholly misguided.
According to RFC 8029 [RFC8029], "If the normal IP return path is According to RFC 8029 [RFC8029], "If the normal IP return path is
deemed unreliable, one may use 3 (Reply via an IPv4/IPv6 UDP packet deemed unreliable, one may use 3 (Reply via an IPv4/IPv6 UDP packet
with Router Alert)." with Router Alert)."
However, it is not clear that the use of the RAO increases the However, it is not clear that the use of the RAO increases the
reliability of the return path. In fact, one can argue it decreases reliability of the return path. In fact, one can argue it decreases
the reliability in many instances, due to the additional burden of the reliability in many instances, due to the additional burden of
processing the RAO. This document updates RFC 8029 [RFC8029] in that processing the RAO. This document updates RFC 8029 [RFC8029] in that
mode 3 is removed. mode 3 is removed.
No implementations of mode 3 have been reported to the MPLS working No implementations of mode 3 have been reported to the MPLS Working
group. Group.
4. Reclassification of RFC 7506 as Historic 3. Reclassification of RFC 7506 as Historic
RFC 7506 [RFC7506] defines the IPv6 Router Alert Option for MPLS RFC 7506 [RFC7506] defines the IPv6 Router Alert Option for MPLS
Operations, Administration, and Management. This document explains Operations, Administration, and Maintenance. This document explains
why RFC 7506 [RFC7506] has been reclassified as Historic. why RFC 7506 [RFC7506] has been reclassified as Historic.
5. Update to RFC 8029 4. Update to RFC 8029
[RFC8029] requires that the IPv6 Destination Address used in IP/UDP [RFC8029] requires that the IPv6 Destination Address used in IP/UDP
encapsulation of an MPLS echo request packet is selected from the encapsulation of an MPLS echo request packet be selected from the
IPv4 loopback address range mapped to IPv6. Such packets do not have IPv4 loopback address range mapped to IPv6. Such packets do not have
the same behavior as prescribed in [RFC1122] for an IPv4 loopback the same behavior as prescribed in [RFC1122] for an IPv4 loopback
addressed packet. addressed packet.
[RFC4291] defines ::1/128 as the single IPv6 loopback address. [RFC4291] defines ::1/128 as the single IPv6 loopback address.
Considering that, this specification updates Section 2.1 of [RFC8029] Considering that, this specification updates Section 2.1 of [RFC8029]
regarding the selection of an IPv6 destination address for an MPLS regarding the selection of an IPv6 destination address for an MPLS
echo request message as follows: echo request message as follows:
OLD OLD:
The 127/8 range for IPv4 and that same range embedded in an
IPv4-mapped IPv6 address for IPv6 was chosen for a number of reasons.
RFC 1122 allocates the 127/8 as the "Internal host loopback address"
and states: "Addresses of this form MUST NOT appear outside a host."
Thus, the default behavior of hosts is to discard such packets. This
helps to ensure that if a diagnostic packet is misdirected to a host,
it will be silently discarded.
RFC 1812 [RFC1812] states:
* A router SHOULD NOT forward, except over a loopback interface, any
packet that has a destination address on network 127. A router
MAY have a switch that allows the network manager to disable these
checks. If such a switch is provided, it MUST default to
performing the checks.
This helps to ensure that diagnostic packets are never IP forwarded.
The 127/8 address range provides 16M addresses allowing wide
flexibility in varying addresses to exercise ECMP paths. Finally, as
an implementation optimization, the 127/8 range provides an easy
means of identifying possible LSP packets.
NEW
The 127/8 range for IPv4 was chosen for a number of reasons.
RFC 1122 [RFC1122] allocates the 127/8 as the "Internal host loopback
address" and states: "Addresses of this form MUST NOT appear outside
a host." Thus, the default behavior of hosts is to discard such
packets. This helps to ensure that if a diagnostic packet is
misdirected to a host, it will be silently discarded.
RFC 1812 [RFC1812] states:
* A router SHOULD NOT forward, except over a loopback interface, any
packet that has a destination address on network 127. A router
MAY have a switch that allows the network manager to disable these
checks. If such a switch is provided, it MUST default to
performing the checks.
This helps to ensure that diagnostic packets are never IP forwarded.
The 127/8 address range provides 16M addresses allowing wide
flexibility in varying addresses to exercise ECMP paths. Finally, as
an implementation optimization, the 127/8 range provides an easy
means of identifying possible LSP packets.
The IPv6 destination address for an MPLS echo request message is
selected as follows:
* The IPv6 loopback address ::1/128 SHOULD be used.
* The sender of an MPLS echo request MAY select the IPv6 destination | The 127/8 range for IPv4 and that same range embedded in an
address from the 0:0:0:0:0:FFFF:7F00/104 range. | IPv4-mapped IPv6 address for IPv6 was chosen for a number of
| reasons.
|
| RFC 1122 allocates the 127/8 as the "Internal host loopback
| address" and states: "Addresses of this form MUST NOT appear
| outside a host." Thus, the default behavior of hosts is to
| discard such packets. This helps to ensure that if a diagnostic
| packet is misdirected to a host, it will be silently discarded.
|
| RFC 1812 [RFC1812] states:
|
| A router SHOULD NOT forward, except over a loopback interface,
| any packet that has a destination address on network 127. A
| router MAY have a switch that allows the network manager to
| disable these checks. If such a switch is provided, it MUST
| default to performing the checks.
|
| This helps to ensure that diagnostic packets are never IP
| forwarded.
|
| The 127/8 address range provides 16M addresses allowing wide
| flexibility in varying addresses to exercise ECMP paths. Finally,
| as an implementation optimization, the 127/8 range provides an
| easy means of identifying possible LSP packets.
* To exercise all paths in an ECMP environment, the source of NEW:
entropy other than the IP destination address SHOULD be used. For
example, MPLS Entropy Label [RFC6790] or IPv6 Flow Label [RFC6438]
can be used as the source of entropy.
END | The 127/8 range for IPv4 was chosen for a number of reasons.
|
| RFC 1122 [RFC1122] allocates the 127/8 as the "Internal host
| loopback address" and states: "Addresses of this form MUST NOT
| appear outside a host." Thus, the default behavior of hosts is to
| discard such packets. This helps to ensure that if a diagnostic
| packet is misdirected to a host, it will be silently discarded.
|
| RFC 1812 [RFC1812] states:
|
| A router SHOULD NOT forward, except over a loopback interface,
| any packet that has a destination address on network 127. A
| router MAY have a switch that allows the network manager to
| disable these checks. If such a switch is provided, it MUST
| default to performing the checks.
|
| This helps to ensure that diagnostic packets are never IP
| forwarded.
|
| The 127/8 address range provides 16M addresses allowing wide
| flexibility in varying addresses to exercise ECMP paths. Finally,
| as an implementation optimization, the 127/8 range provides an
| easy means of identifying possible LSP packets.
|
| The IPv6 destination address for an MPLS echo request message is
| selected as follows:
|
| * The IPv6 loopback address ::1/128 SHOULD be used.
|
| * The sender of an MPLS echo request MAY select the IPv6
| destination address from the 0:0:0:0:0:FFFF:7F00/104 range.
|
| * To exercise all paths in an ECMP environment, the source of
| entropy other than the IP destination address SHOULD be used.
| For example, the MPLS Entropy Label [RFC6790] or IPv6 Flow
| Label [RFC6438] can be used as the source of entropy.
Additionally, this specification updates Section 2.2 of [RFC8029] to Additionally, this specification updates Section 2.2 of [RFC8029] to
replace the whole of the section with the following text: replace the whole of the section with the following text:
LSP Ping implementations SHOULD ignore RAO options when they | LSP Ping implementations SHOULD ignore RAO options when they
arrive on incoming MPLS echo request and MPLS echo reply messages. | arrive on incoming MPLS echo request and MPLS echo reply messages.
Resulting from the removal of the Reply mode 3 "Reply via an IPv4/ Resulting from the removal of the Reply mode 3 "Reply via an IPv4/
IPv6 UDP packet with Router Alert" (see Section 3.2), this IPv6 UDP packet with Router Alert" (see Section 2.2), this
specification updates Section 4.5 of [RFC8029] by removing the specification updates Section 4.5 of [RFC8029] by removing the
following text: following text:
If the Reply Mode in the echo request is "Reply via an IPv4 UDP | If the Reply Mode in the echo request is "Reply via an IPv4 UDP
packet with Router Alert", then the IP header MUST contain the | packet with Router Alert", then the IP header MUST contain the
Router Alert IP Option of value 0x0 [RFC2113] for IPv4 or 69 | Router Alert IP Option of value 0x0 [RFC2113] for IPv4 or 69
[RFC7506] for IPv6. If the reply is sent over an LSP, the topmost | [RFC7506] for IPv6. If the reply is sent over an LSP, the topmost
label MUST in this case be the Router Alert label (1) (see | label MUST in this case be the Router Alert label (1) (see
[RFC3032]). | [RFC3032]).
Furthermore, this specification updates Section 4.3 of [RFC8029] as Furthermore, this specification updates Section 4.3 of [RFC8029] as
follows: follows:
OLD: OLD:
The Router Alert IP Option of value 0x0 [RFC2113] for IPv4 or value | The Router Alert IP Option of value 0x0 [RFC2113] for IPv4 or
69 [RFC7506] for IPv6 MUST be set in the IP header. | value 69 [RFC7506] for IPv6 MUST be set in the IP header.
NEW: NEW:
The Router Alert IP Option of value 0x0 [RFC2113] for IPv4 or value | The Router Alert IP Option of value 0x0 [RFC2113] for IPv4 or
69 [RFC7506] for IPv6 MUST NOT be set in the IP header. | value 69 [RFC7506] for IPv6 MUST NOT be set in the IP header.
END
6. Backwards Compatibility 5. Backwards Compatibility
LSP Ping implementations that conform to this specification SHOULD LSP Ping implementations that conform to this specification SHOULD
ignore RAO options when they arrive on incoming MPLS echo request and ignore RAO options when they arrive on incoming MPLS echo request and
MPLS echo reply messages. However, this will not harm backwards MPLS echo reply messages. However, this will not harm backwards
compatibility because other mechanisms will also be in use by all compatibility because other mechanisms will also be in use by all
legacy implementations in the messages they send and receive. legacy implementations in the messages they send and receive.
Section 7 of this document deprecates the IPv6 RAO value for MPLS OAM Section 6 of this document deprecates the IPv6 RAO value for MPLS OAM
(69) in [IANA-IPV6-RAO] and the Reply Mode 3 ("Reply via an IPv4/IPv6 (69) in [IANA-IPV6-RAO] and the Reply Mode 3 ("Reply via an IPv4/IPv6
UDP packet with Router Alert") in [IANA-LSP-PING]. UDP packet with Router Alert") in [IANA-LSP-PING].
[RFC8126] offers a formal description of the word "Deprecated". In [RFC8126] offers a formal description of the word "Deprecated". In
this context, "Deprecated" means that the deprecated values SHOULD this context, "Deprecated" means that the deprecated values SHOULD
NOT be used in new implementations, and that deployed implementations NOT be used in new implementations, and that deployed implementations
that already use these values continue to work seamlessly. that already use these values continue to work seamlessly.
7. IANA Considerations 6. IANA Considerations
IANA is requested to mark the IPv6 RAO value of MPLS OAM (69) in IANA has marked the IPv6 RAO value of MPLS OAM (69) in
[IANA-IPV6-RAO] as "Deprecated". [IANA-IPV6-RAO] as "DEPRECATED".
IANA is also requested to mark Reply Mode 3 ("Reply via an IPv4/IPv6 IANA has marked Reply Mode 3 ("Reply via an IPv4/IPv6 UDP packet with
UDP packet with Router Alert") in "Multiprotocol Label Switching Router Alert") in "Multiprotocol Label Switching (MPLS) Label
(MPLS) Label Switched Paths (LSPs) Ping Parameters"[IANA-LSP-PING] as Switched Paths (LSPs) Ping Parameters" [IANA-LSP-PING] as
"Deprecated". "DEPRECATED".
8. Security Considerations 7. Security Considerations
The recommendations this document makes do not compromise security. The recommendations this document makes do not compromise security.
In case of using IPv6 loopback address ::1/128 strengthens security Using the IPv6 loopback address ::1/128 strengthens security for LSP
for LSP Ping by using the standardized loopback address with well- ping because it is standardized and has well-defined behavior.
defined behavior.
9. Acknowledgments
The authors express their appreciation to Adrian Farrel and Gyan 8. References
Mishra for their suggestions that improved the readability of the
document.
10. Normative References 8.1. Normative References
[RFC1122] Braden, R., Ed., "Requirements for Internet Hosts - [RFC1122] Braden, R., Ed., "Requirements for Internet Hosts -
Communication Layers", STD 3, RFC 1122, Communication Layers", STD 3, RFC 1122,
DOI 10.17487/RFC1122, October 1989, DOI 10.17487/RFC1122, October 1989,
<https://www.rfc-editor.org/info/rfc1122>. <https://www.rfc-editor.org/info/rfc1122>.
[RFC1812] Baker, F., Ed., "Requirements for IP Version 4 Routers", [RFC1812] Baker, F., Ed., "Requirements for IP Version 4 Routers",
RFC 1812, DOI 10.17487/RFC1812, June 1995, RFC 1812, DOI 10.17487/RFC1812, June 1995,
<https://www.rfc-editor.org/info/rfc1812>. <https://www.rfc-editor.org/info/rfc1812>.
skipping to change at page 9, line 38 skipping to change at line 400
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26, Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017, RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>. <https://www.rfc-editor.org/info/rfc8126>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>. May 2017, <https://www.rfc-editor.org/info/rfc8174>.
11. Informational References 8.2. Informative References
[IANA-IPV6-RAO] [IANA-IPV6-RAO]
IANA, "IPv6 Router Alert Option Values", n.d., IANA, "IPv6 Router Alert Option Values",
<https://www.iana.org/assignments/ipv6-routeralert- <https://www.iana.org/assignments/ipv6-routeralert-
values>. values>.
[IANA-LSP-PING] [IANA-LSP-PING]
IANA, "Multiprotocol Label Switching (MPLS) Label Switched IANA, "Multiprotocol Label Switching (MPLS) Label Switched
Paths (LSPs) Ping Parameters", n.d., Paths (LSPs) Ping Parameters",
<https://www.iana.org/assignments/mpls-lsp-ping- <https://www.iana.org/assignments/mpls-lsp-ping-
parameters/mpls-lsp-ping-parameters.xml>. parameters>.
[RFC3032] Rosen, E., Tappan, D., Fedorkow, G., Rekhter, Y.,
Farinacci, D., Li, T., and A. Conta, "MPLS Label Stack
Encoding", RFC 3032, DOI 10.17487/RFC3032, January 2001,
<https://www.rfc-editor.org/info/rfc3032>.
[RFC6438] Carpenter, B. and S. Amante, "Using the IPv6 Flow Label [RFC6438] Carpenter, B. and S. Amante, "Using the IPv6 Flow Label
for Equal Cost Multipath Routing and Link Aggregation in for Equal Cost Multipath Routing and Link Aggregation in
Tunnels", RFC 6438, DOI 10.17487/RFC6438, November 2011, Tunnels", RFC 6438, DOI 10.17487/RFC6438, November 2011,
<https://www.rfc-editor.org/info/rfc6438>. <https://www.rfc-editor.org/info/rfc6438>.
[RFC6790] Kompella, K., Drake, J., Amante, S., Henderickx, W., and [RFC6790] Kompella, K., Drake, J., Amante, S., Henderickx, W., and
L. Yong, "The Use of Entropy Labels in MPLS Forwarding", L. Yong, "The Use of Entropy Labels in MPLS Forwarding",
RFC 6790, DOI 10.17487/RFC6790, November 2012, RFC 6790, DOI 10.17487/RFC6790, November 2012,
<https://www.rfc-editor.org/info/rfc6790>. <https://www.rfc-editor.org/info/rfc6790>.
Acknowledgments
The authors express their appreciation to Adrian Farrel and Gyan
Mishra for their suggestions that improved the readability of the
document.
Authors' Addresses Authors' Addresses
Kireeti Kompella Kireeti Kompella
Juniper Networks Juniper Networks
1133 Innovation Way 1133 Innovation Way
Sunnyvale, CA 94089 Sunnyvale, CA 94089
United States United States of America
Email: kireeti.ietf@gmail.com Email: kireeti.ietf@gmail.com
Ron Bonica Ron Bonica
Juniper Networks Juniper Networks
1133 Innovation Way 1133 Innovation Way
Sunnyvale, CA 94089 Sunnyvale, CA 94089
United States United States of America
Email: rbonica@juniper.net Email: rbonica@juniper.net
Greg Mirsky (editor) Greg Mirsky (editor)
Ericsson Ericsson
Email: gregimirsky@gmail.com Email: gregimirsky@gmail.com
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