draft-ietf-6man-ext-transmit-03.txt   draft-ietf-6man-ext-transmit-04.txt 
6man B. Carpenter 6man B. Carpenter
Internet-Draft Univ. of Auckland Internet-Draft Univ. of Auckland
Updates: 2460, 2780 (if approved) S. Jiang Updates: 2460, 2780 (if approved) S. Jiang
Intended status: Standards Track Huawei Technologies Co., Ltd Intended status: Standards Track Huawei Technologies Co., Ltd
Expires: February 23, 2014 August 22, 2013 Expires: March 30, 2014 September 26, 2013
Transmission and Processing of IPv6 Extension Headers Transmission and Processing of IPv6 Extension Headers
draft-ietf-6man-ext-transmit-03 draft-ietf-6man-ext-transmit-04
Abstract Abstract
Various IPv6 extension headers have been standardised since the IPv6 Various IPv6 extension headers have been standardised since the IPv6
standard was first published. This document updates RFC 2460 to standard was first published. This document updates RFC 2460 to
clarify how intermediate nodes should deal with such extension clarify how intermediate nodes should deal with such extension
headers and with any that are defined in future. It also specifies headers and with any that are defined in future. It also specifies
how extension headers should be registered by IANA, with a how extension headers should be registered by IANA, with a
corresponding minor update to RFC 2780. corresponding minor update to RFC 2780.
skipping to change at page 1, line 36 skipping to change at page 1, line 36
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on February 23, 2014. This Internet-Draft will expire on March 30, 2014.
Copyright Notice Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction and Problem Statement . . . . . . . . . . . . . 2 1. Introduction and Problem Statement . . . . . . . . . . . . . 2
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
2. Requirement to Transmit Extension Headers . . . . . . . . . . 4 2. Requirement to Transmit Extension Headers . . . . . . . . . . 5
2.1. All Extension Headers . . . . . . . . . . . . . . . . . . 4 2.1. All Extension Headers . . . . . . . . . . . . . . . . . . 5
2.2. Hop-by-Hop Options . . . . . . . . . . . . . . . . . . . 5 2.2. Hop-by-Hop Options . . . . . . . . . . . . . . . . . . . 6
3. Security Considerations . . . . . . . . . . . . . . . . . . . 6 3. Security Considerations . . . . . . . . . . . . . . . . . . . 6
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 7 5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 7
6. Change log [RFC Editor: Please remove] . . . . . . . . . . . 7 6. Change log [RFC Editor: Please remove] . . . . . . . . . . . 8
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 8
7.1. Normative References . . . . . . . . . . . . . . . . . . 8 7.1. Normative References . . . . . . . . . . . . . . . . . . 9
7.2. Informative References . . . . . . . . . . . . . . . . . 9 7.2. Informative References . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10
1. Introduction and Problem Statement 1. Introduction and Problem Statement
In IPv6, an extension header is any header that follows the initial In IPv6, an extension header is any header that follows the initial
40 bytes of the packet and precedes the upper layer header (which 40 bytes of the packet and precedes the upper layer header (which
might be a transport header, an ICMPv6 header, or a notional "No Next might be a transport header, an ICMPv6 header, or a notional "No Next
Header"). Header").
An initial set of IPv6 extension headers was defined by [RFC2460], An initial set of IPv6 extension headers was defined by [RFC2460],
which also described how they should be handled by intermediate which also described how they should be handled by intermediate
skipping to change at page 3, line 4 skipping to change at page 3, line 4
forwarding nodes to modify them, remove them, insert them, or use forwarding nodes to modify them, remove them, insert them, or use
them to affect forwarding behaviour. Thus, new extension headers them to affect forwarding behaviour. Thus, new extension headers
could be introduced progressively, used only by hosts that have been could be introduced progressively, used only by hosts that have been
updated to create and interpret them [RFC6564]. The extension header updated to create and interpret them [RFC6564]. The extension header
mechanism is an important part of the IPv6 architecture, and several mechanism is an important part of the IPv6 architecture, and several
new extension headers have been standardised since RFC 2460. new extension headers have been standardised since RFC 2460.
Today, packets are often forwarded not only by straightforward IP Today, packets are often forwarded not only by straightforward IP
routers, but also by a variety of intermediate nodes, often referred routers, but also by a variety of intermediate nodes, often referred
to as middleboxes, such as firewalls, load balancers, or packet to as middleboxes, such as firewalls, load balancers, or packet
classifiers. However, experience has showed that as a result, the classifiers. However, experience has shown that as a result, the
network is not transparent to IPv6 extension headers. Contrary to network is not transparent to IPv6 extension headers. Contrary to
Section 4 of RFC 2460, middleboxes sometimes examine and process the Section 4 of RFC 2460, middleboxes sometimes examine and process the
entire IPv6 packet before making a decision to either forward or entire IPv6 packet before making a decision to either forward or
discard the packet. This means that they need to traverse the chain discard the packet. This means that they need to traverse the chain
of extension headers, if present, until they find the transport of extension headers, if present, until they find the transport
header (or an encrypted payload). Unfortunately, because not all header (or an encrypted payload). Unfortunately, because not all
IPv6 extension headers follow a uniform TLV format, this process is IPv6 extension headers follow a uniform TLV format, this process is
clumsy and requires knowledge of each extension header's format. A clumsy and requires knowledge of each extension header's format. A
separate problem is that the header chain may even be fragmented separate problem is that the header chain may even be fragmented
[I-D.ietf-6man-oversized-header-chain]. [I-D.ietf-6man-oversized-header-chain].
The process is potentially slow as well as clumsy, possibly The process is potentially slow as well as clumsy, possibly
precluding its use in nodes attempting to process packets at line precluding its use in nodes attempting to process packets at line
speed. The present document does not intend to solve this problem, speed. The present document does not intend to solve this problem,
which is caused by the fundamental architecture of IPv6 extension which is caused by the fundamental architecture of IPv6 extension
headers. This document focuses on clarifying how the header chain headers. This document focuses on clarifying how the header chain
should be traversed in the current IPv6 architecture. should be handled in the current IPv6 architecture.
If they encounter an unrecognised extension header type, some If they encounter an unrecognised extension header type, some
firewalls treat the packet as suspect and drop it. Unfortunately, it firewalls treat the packet as suspect and drop it. Unfortunately, it
is an established fact that several widely used firewalls do not is an established fact that several widely used firewalls do not
recognise some or all of the extension headers standardised since RFC recognise some or all of the extension headers standardised since RFC
2460. It has also been observed that certain firewalls do not even 2460. It has also been observed that certain firewalls do not even
handle all the extension headers standardised in RFC 2460, including handle all the extension headers standardised in RFC 2460, including
the fragment header [I-D.taylor-v6ops-fragdrop], causing fundamental the fragment header [I-D.taylor-v6ops-fragdrop], causing fundamental
problems of end-to-end connectivity. This applies in particular to problems of end-to-end connectivity. This applies in particular to
firewalls that attempt to inspect packets at very high speed, since firewalls that attempt to inspect packets at very high speed, since
skipping to change at page 4, line 17 skipping to change at page 4, line 17
The uniform TLV format now defined for extension headers [RFC6564] The uniform TLV format now defined for extension headers [RFC6564]
will improve the situation, but only for future extensions. Some will improve the situation, but only for future extensions. Some
tricky and potentially malicious cases will be avoided by forbidding tricky and potentially malicious cases will be avoided by forbidding
very long chains of extension headers that need to be fragmented very long chains of extension headers that need to be fragmented
[I-D.ietf-6man-oversized-header-chain]. This will alleviate concerns [I-D.ietf-6man-oversized-header-chain]. This will alleviate concerns
that stateless firewalls cannot locate a complete header chain as that stateless firewalls cannot locate a complete header chain as
required by the present document. required by the present document.
However, these changes are insufficient to correct the underlying However, these changes are insufficient to correct the underlying
problem. The present document clarifies that the above requirement problem. The present document clarifies that the above requirement
from RFC 2460 applies to all types of node that forward IPv6 packets from RFC 2460 applies to all types of nodes that forward IPv6 packets
and to all extension headers standardised now and in the future. It and to all extension headers standardised now and in the future. It
also requests IANA to create a subsidiary registry that clearly also requests IANA to create a subsidiary registry that clearly
identifies extension header types, and updates RFC 2780 accordingly. identifies extension header types, and updates RFC 2780 accordingly.
Fundamental changes to the IPv6 extension header architecture are out Fundamental changes to the IPv6 extension header architecture are out
of scope for this document. of scope for this document.
Also, Hop-by-Hop options are not handled by many high speed routers, Also, Hop-by-Hop options are not handled by many high speed routers,
or are processed only on a slow path. This document also updates the or are processed only on a slow path. This document also updates the
requirements for processing the Hop-by-Hop options header to make requirements for processing the Hop-by-Hop options header to make
them more realistic. them more realistic.
skipping to change at page 4, line 40 skipping to change at page 4, line 40
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. document are to be interpreted as described in [RFC2119].
In the remainder of this document, the term "forwarding node" refers In the remainder of this document, the term "forwarding node" refers
to any router, firewall, load balancer, prefix translator, or any to any router, firewall, load balancer, prefix translator, or any
other device or middlebox that forwards IPv6 packets with or without other device or middlebox that forwards IPv6 packets with or without
examining the packet in any way. examining the packet in any way.
In this document "standard" IPv6 extension headers are those
specified in detail by IETF standards actions. "Experimental"
extension headers are those defined by any Experimental RFC, and the
experimental extension header values 253 and 254 defined by [RFC3692]
and [RFC4727]. "Defined" extension headers are the "standard"
extension headers plus the "experimental" ones.
2. Requirement to Transmit Extension Headers 2. Requirement to Transmit Extension Headers
2.1. All Extension Headers 2.1. All Extension Headers
As mentioned above, forwarding nodes that discard packets containing
extension headers are known to cause connectivity failures and
deployment problems. Therefore, it is important that forwarding
nodes that inspect IPv6 headers can parse all defined extension
headers and deal with them appropriately, as specified in this
section.
Any forwarding node along an IPv6 packet's path, which forwards the Any forwarding node along an IPv6 packet's path, which forwards the
packet for any reason, SHOULD do so regardless of any extension packet for any reason, SHOULD do so regardless of any extension
headers that are present, as required by RFC 2460. Exceptionally, if headers that are present, as required by RFC 2460. Exceptionally, if
this node is designed to examine extension headers for any reason, a forwarding node is designed to examine extension headers for any
such as firewalling, it MUST recognise and deal appropriately with reason, such as firewalling, it MUST recognise and deal appropriately
all standardised IPv6 extension header types and SHOULD recognise with all standard IPv6 extension header types and SHOULD recognise
experimental IPv6 extension header types. The list of standardised and deal appropriately with experimental IPv6 extension header types.
and experimental extension header types is maintained by IANA (see The list of standard and experimental extension header types is
Section 4) and implementors are advised to check this list regularly maintained by IANA (see Section 4) and implementors are advised to
for updates. check this list regularly for updates.
RFC 2460 requires destination hosts to discard packets containing RFC 2460 requires destination hosts to discard packets containing
unrecognised extension headers. However, intermediate forwarding unrecognised extension headers. However, intermediate forwarding
nodes SHOULD NOT do this by default, since that might cause them to nodes SHOULD NOT do this, since that might cause them to
inadvertently discard traffic using a recently standardised extension inadvertently discard traffic using a recently standardised extension
header, not yet recognised by the intermediate node. The only header, not yet recognised by the intermediate node. The exceptions
exceptions to this rule are discussed below. to this rule are discussed next.
As mentioned above, forwarding nodes that discard packets containing
extension headers are known to cause connectivity failures and
deployment problems. Therefore, it is important that forwarding
nodes that inspect IPv6 extension headers can parse all standard
headers and are able to behave according to the above requirements.
If a forwarding node discards a packet containing a standard IPv6 If a forwarding node discards a packet containing a standard IPv6
extension header, it MUST be the result of a configurable policy, and extension header, it MUST be the result of a configurable policy, and
not just the result of a failure to recognise such a header. This not just the result of a failure to recognise such a header. This
means that the discard policy for each standardised type of extension means that the discard policy for each standard type of extension
header MUST be individually configurable. The default configuration header MUST be individually configurable. The default configuration
SHOULD allow all standardised extension headers. SHOULD allow all standard extension headers.
Experimental IPv6 extension headers, including types 253 and 254 Experimental IPv6 extension headers SHOULD be treated in the same way
defined by [RFC3692] and [RFC4727], SHOULD be treated in the same way as standard extension headers, including an individually configurable
as standardised extension headers, but they MAY be dropped by discard policy. However, the default configuration MAY drop
default. experimental extension headers.
Forwarding nodes MUST be configurable to allow packets containing Forwarding nodes MUST be configurable to allow packets containing
unrecognised extension headers, but such packets MAY be dropped by unrecognised extension headers, but the default configuration MAY
default. drop such packets.
The IPv6 Routing Header Types 0 and 1 have been deprecated [RFC5095]. The IPv6 Routing Header Types 0 and 1 have been deprecated [RFC5095].
However, this does not mean that the IPv6 Routing Header can be However, this does not mean that the IPv6 Routing Header can be
unconditionally dropped by forwarding nodes. Packets containing unconditionally dropped by forwarding nodes. Packets containing
standardised and undeprecated Routing Headers SHOULD be forwarded by standardised and undeprecated Routing Headers SHOULD be forwarded by
default. At the time of writing, these include Type 2 [RFC6275], default. At the time of writing, these include Type 2 [RFC6275],
Type 3 [RFC6554], and the experimental Routing Header Types 253 and Type 3 [RFC6554], and the experimental Routing Header Types 253 and
254 [RFC4727]. Others may be defined in future. 254 [RFC4727]. Others may be defined in future.
2.2. Hop-by-Hop Options 2.2. Hop-by-Hop Options
skipping to change at page 6, line 13 skipping to change at page 6, line 26
this likely behaviour. this likely behaviour.
As a reminder, in RFC 2460, it is stated that the Hop-by-Hop Options As a reminder, in RFC 2460, it is stated that the Hop-by-Hop Options
header, if present, must be first. header, if present, must be first.
3. Security Considerations 3. Security Considerations
Forwarding nodes that operate as firewalls MUST conform to the Forwarding nodes that operate as firewalls MUST conform to the
requirements in the previous section in order to respect the IPv6 requirements in the previous section in order to respect the IPv6
extension header architecture. In particular, packets containing extension header architecture. In particular, packets containing
standard extension headers are only to be discarded as a result of a standard extension headers are only to be discarded as a result of an
configurable policy. intentionally configured policy.
These changes do not affect a firewall's ability to filter out
traffic containing unwanted or suspect extension headers, if
configured to do so. However, the changes do require firewalls to be
capable of permitting any or all extension headers, if configured to
do so. The default configurations are intended to allow normal use
of any standard extension header, avoiding the connectivity issues
described in Section 1 and Section 2.1.
When new extension headers are standardised in the future, those When new extension headers are standardised in the future, those
implementing and configuring forwarding nodes, including firewalls, implementing and configuring forwarding nodes, including firewalls,
will need to take account of them. A newly defined header will will need to take them into account. A newly defined header will
exercise new code paths in a host that does recognise it, so caution exercise new code paths in a host that does recognise it, so caution
may be required. It is therefore to be expected that the deployment may be required. Additional security issues with experimental values
process will be slow and will depend on satisfactory operational or new extension headers are to be found in [RFC4727] and [RFC6564].
experience. Until it is complete, the new extension will fail in As a result, it is to be expected that the deployment process will be
some parts of the Internet. This aspect needs to be considered when slow and will depend on satisfactory operational experience. Until
deciding to standardise a new extension. Specific security deployment is complete, the new extension will fail in some parts of
considerations for each new extension should be documented in the the Internet. This aspect needs to be considered when deciding to
document that defines it. standardise a new extension. Specific security considerations for
each new extension should be documented in the document that defines
it.
4. IANA Considerations 4. IANA Considerations
IANA is requested to clearly mark in the Assigned Internet Protocol IANA is requested to clearly mark in the Assigned Internet Protocol
Numbers registry those values which are also IPv6 Extension Header Numbers registry those values which are also IPv6 Extension Header
types defined by an IETF action, for example by adding an extra types defined by an IETF Standards Action or IESG Approval (see list
column to indicate this. This will also apply to any IPv6 Extension below), for example by adding an extra column title "IPv6 Extension
Header" to indicate this. This will also apply to any IPv6 Extension
Header types defined in the future. Header types defined in the future.
Additionally, IANA is requested to replace the existing empty IPv6 Additionally, IANA is requested to make the existing empty IPv6 Next
Next Header Types registry by an IPv6 Extension Header Types Header Types registry redirect users to a new IPv6 Extension Header
registry. It will contain only those protocol numbers which are also Types registry. It will contain only those protocol numbers which
marked as IPv6 Extension Header types in the Assigned Internet are also marked as IPv6 Extension Header types in the Assigned
Protocol Numbers registry. Experimental values will be marked as Internet Protocol Numbers registry. Experimental values will be
such. The initial list will be as follows: marked as such. The initial list will be as follows:
o 0, Hop-by-Hop Options, [RFC2460] o 0, Hop-by-Hop Options, [RFC2460]
o 43, Routing, [RFC2460], [RFC5095] o 43, Routing, [RFC2460], [RFC5095]
o 44, Fragment, [RFC2460] o 44, Fragment, [RFC2460]
o 50, Encapsulating Security Payload, [RFC4303] o 50, Encapsulating Security Payload, [RFC4303]
o 51, Authentication, [RFC4302] o 51, Authentication, [RFC4302]
skipping to change at page 7, line 20 skipping to change at page 7, line 47
o 140, shim6, [RFC5533] o 140, shim6, [RFC5533]
o 253, experimental use, [RFC3692], [RFC4727] o 253, experimental use, [RFC3692], [RFC4727]
o 254, experimental use, [RFC3692], [RFC4727] o 254, experimental use, [RFC3692], [RFC4727]
This list excludes type 59, No Next Header, [RFC2460], which is not This list excludes type 59, No Next Header, [RFC2460], which is not
an extension header as such. an extension header as such.
The references to the IPv6 Next Header field in [RFC2780] are to be The references to the IPv6 Next Header field in [RFC2780] are to be
interpreted as also applying to the IPv6 Extension Header field. interpreted as also applying to the IPv6 Extension Header field and
the IPv6 Extension Header Types registry will be managed accordingly.
5. Acknowledgements 5. Acknowledgements
This document was triggered by mailing list discussions including This document was triggered by mailing list discussions including
John Leslie, Stefan Marksteiner and others. Valuable comments and John Leslie, Stefan Marksteiner and others. Valuable comments and
contributions were made by Dominique Barthel, Tim Chown, Lorenzo contributions were made by Dominique Barthel, Tim Chown, Lorenzo
Colitti, Fernando Gont, C. M. Heard, Bob Hinden, Ray Hunter, Suresh Colitti, Fernando Gont, C. M. Heard, Bob Hinden, Ray Hunter, Suresh
Krishnan, Marc Lampo, Michael Richardson, Dave Thaler, Joe Touch, Krishnan, Marc Lampo, Sandra Murphy, Michael Richardson, Dan
Bjoern Zeeb, and others. Romascanu, Dave Thaler, Joe Touch, Bjoern Zeeb, and others.
Brian Carpenter was a visitor at the Computer Laboratory, Cambridge Brian Carpenter was a visitor at the Computer Laboratory, Cambridge
University during part of this work. University during part of this work.
This document was produced using the xml2rfc tool [RFC2629]. This document was produced using the xml2rfc tool [RFC2629].
6. Change log [RFC Editor: Please remove] 6. Change log [RFC Editor: Please remove]
draft-ietf-6man-ext-transmit-04: updates following IETF Last Call,
normative requirements clarified, IANA considerations clarified,
security consuderations expanded, 2013-09-26.
draft-ietf-6man-ext-transmit-03: added details for experimental draft-ietf-6man-ext-transmit-03: added details for experimental
values, various clarifications and minor corrections, 2013-08-22. values, various clarifications and minor corrections, 2013-08-22.
draft-ietf-6man-ext-transmit-02: explicit mention of header types 253 draft-ietf-6man-ext-transmit-02: explicit mention of header types 253
and 254, editorial fixes, 2013-08-06. and 254, editorial fixes, 2013-08-06.
draft-ietf-6man-ext-transmit-01: tuned use of normative language, draft-ietf-6man-ext-transmit-01: tuned use of normative language,
clarified that only standardised extensions are covered (hence clarified that only standardised extensions are covered (hence
excluding HIP), 2013-05-29. excluding HIP), 2013-05-29.
skipping to change at page 8, line 32 skipping to change at page 9, line 19
[RFC2460] Deering, S. and R. Hinden, "Internet Protocol, Version 6 [RFC2460] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", RFC 2460, December 1998. (IPv6) Specification", RFC 2460, December 1998.
[RFC2780] Bradner, S. and V. Paxson, "IANA Allocation Guidelines For [RFC2780] Bradner, S. and V. Paxson, "IANA Allocation Guidelines For
Values In the Internet Protocol and Related Headers", BCP Values In the Internet Protocol and Related Headers", BCP
37, RFC 2780, March 2000. 37, RFC 2780, March 2000.
[RFC3692] Narten, T., "Assigning Experimental and Testing Numbers [RFC3692] Narten, T., "Assigning Experimental and Testing Numbers
Considered Useful", BCP 82, RFC 3692, January 2004. Considered Useful", BCP 82, RFC 3692, January 2004.
[RFC4302] Kent, S., "IP Authentication Header", RFC 4302, December
2005.
[RFC4303] Kent, S., "IP Encapsulating Security Payload (ESP)", RFC
4303, December 2005.
[RFC4727] Fenner, B., "Experimental Values In IPv4, IPv6, ICMPv4, [RFC4727] Fenner, B., "Experimental Values In IPv4, IPv6, ICMPv4,
ICMPv6, UDP, and TCP Headers", RFC 4727, November 2006. ICMPv6, UDP, and TCP Headers", RFC 4727, November 2006.
[RFC5095] Abley, J., Savola, P., and G. Neville-Neil, "Deprecation
of Type 0 Routing Headers in IPv6", RFC 5095, December
2007.
[RFC5201] Moskowitz, R., Nikander, P., Jokela, P., and T. Henderson,
"Host Identity Protocol", RFC 5201, April 2008.
[RFC5533] Nordmark, E. and M. Bagnulo, "Shim6: Level 3 Multihoming
Shim Protocol for IPv6", RFC 5533, June 2009.
[RFC6275] Perkins, C., Johnson, D., and J. Arkko, "Mobility Support
in IPv6", RFC 6275, July 2011.
[RFC6564] Krishnan, S., Woodyatt, J., Kline, E., Hoagland, J., and [RFC6564] Krishnan, S., Woodyatt, J., Kline, E., Hoagland, J., and
M. Bhatia, "A Uniform Format for IPv6 Extension Headers", M. Bhatia, "A Uniform Format for IPv6 Extension Headers",
RFC 6564, April 2012. RFC 6564, April 2012.
7.2. Informative References 7.2. Informative References
[Heller] Heller, J., "Catch-22", Simon and Schuster , 1961. [Heller] Heller, J., "Catch-22", Simon and Schuster , 1961.
[I-D.ietf-6man-oversized-header-chain] [I-D.ietf-6man-oversized-header-chain]
Gont, F., Manral, V., and R. Bonica, "Implications of Gont, F., Manral, V., and R. Bonica, "Implications of
Oversized IPv6 Header Chains", draft-ietf-6man-oversized- Oversized IPv6 Header Chains", draft-ietf-6man-oversized-
header-chain-04 (work in progress), August 2013. header-chain-07 (work in progress), September 2013.
[I-D.taylor-v6ops-fragdrop] [I-D.taylor-v6ops-fragdrop]
Jaeggli, J., Colitti, L., Kumari, W., Vyncke, E., Kaeo, Jaeggli, J., Colitti, L., Kumari, W., Vyncke, E., Kaeo,
M., and T. Taylor, "Why Operators Filter Fragments and M., and T. Taylor, "Why Operators Filter Fragments and
What It Implies", draft-taylor-v6ops-fragdrop-01 (work in What It Implies", draft-taylor-v6ops-fragdrop-01 (work in
progress), June 2013. progress), June 2013.
[RFC2629] Rose, M., "Writing I-Ds and RFCs using XML", RFC 2629, [RFC2629] Rose, M., "Writing I-Ds and RFCs using XML", RFC 2629,
June 1999. June 1999.
[RFC4302] Kent, S., "IP Authentication Header", RFC 4302, December
2005.
[RFC4303] Kent, S., "IP Encapsulating Security Payload (ESP)", RFC
4303, December 2005.
[RFC5095] Abley, J., Savola, P., and G. Neville-Neil, "Deprecation
of Type 0 Routing Headers in IPv6", RFC 5095, December
2007.
[RFC5201] Moskowitz, R., Nikander, P., Jokela, P., and T. Henderson,
"Host Identity Protocol", RFC 5201, April 2008.
[RFC5533] Nordmark, E. and M. Bagnulo, "Shim6: Level 3 Multihoming
Shim Protocol for IPv6", RFC 5533, June 2009.
[RFC6275] Perkins, C., Johnson, D., and J. Arkko, "Mobility Support
in IPv6", RFC 6275, July 2011.
[RFC6554] Hui, J., Vasseur, JP., Culler, D., and V. Manral, "An IPv6 [RFC6554] Hui, J., Vasseur, JP., Culler, D., and V. Manral, "An IPv6
Routing Header for Source Routes with the Routing Protocol Routing Header for Source Routes with the Routing Protocol
for Low-Power and Lossy Networks (RPL)", RFC 6554, March for Low-Power and Lossy Networks (RPL)", RFC 6554, March
2012. 2012.
Authors' Addresses Authors' Addresses
Brian Carpenter Brian Carpenter
Department of Computer Science Department of Computer Science
University of Auckland University of Auckland
 End of changes. 34 change blocks. 
78 lines changed or deleted 102 lines changed or added

This html diff was produced by rfcdiff 1.41. The latest version is available from http://tools.ietf.org/tools/rfcdiff/