draft-ietf-6man-flow-update-04.txt   draft-ietf-6man-flow-update-05.txt 
6MAN S. Amante 6MAN S. Amante
Internet-Draft Level 3 Internet-Draft Level 3
Intended status: Informational B. Carpenter Intended status: Informational B. Carpenter
Expires: September 14, 2011 Univ. of Auckland Expires: November 3, 2011 Univ. of Auckland
S. Jiang S. Jiang
Huawei Technologies Co., Ltd Huawei Technologies Co., Ltd
March 13, 2011 May 2, 2011
Rationale for update to the IPv6 flow label specification Rationale for update to the IPv6 flow label specification
draft-ietf-6man-flow-update-04 draft-ietf-6man-flow-update-05
Abstract Abstract
Various published proposals for use of the IPv6 flow label are Various published proposals for use of the IPv6 flow label are
incompatible with its original specification in RFC 3697. incompatible with its original specification in RFC 3697.
Furthermore, very little practical use is made of the flow label, Furthermore, very little practical use is made of the flow label,
partly due to some uncertainties about the correct interpretation of partly due to some uncertainties about the correct interpretation of
the specification. This document discusses and motivates changes to the specification. This document discusses and motivates changes to
the specification in order to clarify it, and to introduce some the specification in order to clarify it, and to introduce some
additional flexibility. additional flexibility.
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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 September 14, 2011. This Internet-Draft will expire on November 3, 2011.
Copyright Notice Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the Copyright (c) 2011 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
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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 . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Impact of current specification . . . . . . . . . . . . . . . 3 2. Impact of current specification . . . . . . . . . . . . . . . 3
3. Changes to specification . . . . . . . . . . . . . . . . . . . 6 3. Changes to specification . . . . . . . . . . . . . . . . . . . 6
4. Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4. Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . 8
5. Security Considerations . . . . . . . . . . . . . . . . . . . 8 5. Security Considerations . . . . . . . . . . . . . . . . . . . 9
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 8 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 9
8. Change log . . . . . . . . . . . . . . . . . . . . . . . . . . 9 8. Change log [RFC Editor: please remove] . . . . . . . . . . . . 10
9. Informative References . . . . . . . . . . . . . . . . . . . . 9 9. Informative References . . . . . . . . . . . . . . . . . . . . 10
Appendix A. Alternative Approaches . . . . . . . . . . . . . . . 10 Appendix A. Alternative Approaches . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 11 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 12
1. Introduction 1. Introduction
The flow label field in the IPv6 header was reserved but left The flow label field in the IPv6 header was reserved but left
experimental by [RFC2460], which mandates only that "Hosts or routers experimental by [RFC2460], which mandates only that "Hosts or routers
that do not support the functions of the Flow Label field are that do not support the functions of the Flow Label field are
required to set the field to zero when originating a packet, pass the required to set the field to zero when originating a packet, pass the
field on unchanged when forwarding a packet, and ignore the field field on unchanged when forwarding a packet, and ignore the field
when receiving a packet." when receiving a packet."
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lack of them, of the flow label. The flow label field is always lack of them, of the flow label. The flow label field is always
unprotected as it travels through the network, because there is no unprotected as it travels through the network, because there is no
IPv6 header checksum, and the flow label is not included in transport IPv6 header checksum, and the flow label is not included in transport
pseudo-header checksums, nor in IPsec checksums. As a result, pseudo-header checksums, nor in IPsec checksums. As a result,
intentional and malicious changes to its value cannot be detected. intentional and malicious changes to its value cannot be detected.
Also, it could be used as a covert data channel, since apparently Also, it could be used as a covert data channel, since apparently
pseudo-random flow label values could in fact consist of covert data. pseudo-random flow label values could in fact consist of covert data.
If the flow label were to carry quality of service semantics, then If the flow label were to carry quality of service semantics, then
like the diffserv code point [RFC2474], it would not be intrinsically like the diffserv code point [RFC2474], it would not be intrinsically
trustworthy across domain boundaries. As a result, some security trustworthy across domain boundaries. As a result, some security
specialists believe that flow labels should be cleared for safety. specialists believe that flow labels should be cleared for safety
These points must be considered when discussing the immutability of [I-D.gont-6man-flowlabel-security]. These points must be considered
the flow label across domain boundaries. when discussing the immutability of the flow label across domain
boundaries.
Rule (b) appears to forbid any usage in which the bits of the flow Rule (b) appears to forbid any usage in which the bits of the flow
label are encoded with a specific semantic meaning. However, the label are encoded with a specific semantic meaning. However, the
words "MUST NOT assume" are to be interpreted precisely - if a router words "MUST NOT assume" are to be interpreted precisely - if a router
knows by configuration or by signaling that the flow label has been knows by configuration or by signaling that the flow label has been
assigned in a certain way, it can make use of that knowledge. It is assigned in a certain way, it can make use of that knowledge. It is
not made clear by the rule that there is an implied distinction not made clear by the rule that there is an implied distinction
between stateless models (in which case no assumption may be made) between stateless models (in which case no assumption may be made)
and stateful models (in which the router has explicit knowledge). and stateful models (in which the router has explicit knowledge).
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other proposals discussed in [I-D.hu-flow-label-cases] appear to be other proposals discussed in [I-D.hu-flow-label-cases] appear to be
compatible with RFC 3697. Several are based on the originator of a compatible with RFC 3697. Several are based on the originator of a
packet choosing a pseudo-random flow label for each flow, which is packet choosing a pseudo-random flow label for each flow, which is
one option suggested in RFC 3697. Thus, we can also conclude that one option suggested in RFC 3697. Thus, we can also conclude that
there is a useful role for this approach. there is a useful role for this approach.
If our goal is for the flow label to be used in practice, the If our goal is for the flow label to be used in practice, the
conflict between the various approaches creates a dilemma. There conflict between the various approaches creates a dilemma. There
appear to be two major options: appear to be two major options:
1. Discourage locally defined and/or stateful use of the flow label. 1. Discourage locally defined and/or stateful use of the flow label.
Strengthen RFC 3697 to say that hosts SHOULD set a pseudo-random Strengthen RFC 3697 to say that hosts should set a label value,
label value, without creating state, which would clarify and without necessarily creating state, which would clarify and limit
limit its possible uses. In particular, its use for load its possible uses. In particular, its use for load distribution
distribution and balancing would be encouraged. and balancing would be encouraged.
2. Relax the rules to encourage locally defined and/or stateful use 2. Relax the rules to encourage locally defined and/or stateful use
of the flow label. This approach would make the flow label of the flow label. This approach would make the flow label
completely mutable and would exclude use cases depending on completely mutable and would exclude use cases depending on
strict end-to-end immutability. It would encourage applications strict end-to-end immutability. It would encourage applications
of a pseudo-random flow label, such as load distribution, on a of a pseudo-random flow label, such as load distribution, on a
local basis, but it would exclude end-to-end applications. local basis, but it would exclude end-to-end applications.
During 2010 there was considerable debate about these options and During 2010/2011 there was considerable debate about these options
variants of them, with a variety of proposals in previous versions of and variants of them, with a variety of proposals in previous
this document and in mailing list discussions. After these versions of this document and in mailing list discussions. After
discussions, there appears to be a view that simplicity should these discussions, there appears to be a view that simplicity should
prevail, and that complicated proposals such as defining quality of prevail, and that complicated proposals such as defining quality of
service semantics in the flow label, or sub-dividing the flow label service semantics in the flow label, or sub-dividing the flow label
field into smaller sub-fields, will not prove efficient or field into smaller sub-fields, will not prove efficient or
deployable, especially in high speed routers. There is also a deployable, especially in high speed routers. There is also a
clearly expressed view that using the flow label for various forms of clearly expressed view that using the flow label for various forms of
stateless load distribution is the best simple application for it. stateless load distribution is the best simple application for it.
At the same time, it is necessary to recognize that the strict At the same time, it is necessary to recognize that the strict
immutability rule has drawbacks as noted above. immutability rule has drawbacks as noted above.
Even under the rules of RFC 3697, the flow label is intrinsically Even under the rules of RFC 3697, the flow label is intrinsically
untrustworthy, because modifications en route cannot be detected. untrustworthy, because modifications en route cannot be detected.
For this reason, even with the current strict immutability rule, For this reason, even with the current strict immutability rule,
downstream nodes cannot rely on the value being unchanged. In this downstream nodes cannot rely mathematically on the value being
sense, any use of the flow label must be viewed as an optimisation on unchanged. In this sense, any use of the flow label must be viewed
a best effort basis; a packet with a changed (or zero) flow label as an optimisation on a best effort basis; a packet with a changed
value should never cause a hard failure. (or zero) flow label value should never cause a hard failure.
The remainder of this document discusses specific modifications to The remainder of this document discusses specific modifications to
the standard, which are defined normatively in a companion document the standard, which are defined normatively in a companion document
[I-D.ietf-6man-flow-3697bis]. [I-D.ietf-6man-flow-3697bis].
3. Changes to specification 3. Changes to specification
Although RFC 3697 requires the flow label to be delivered unchanged, Although RFC 3697 requires the flow label to be delivered unchanged,
as noted above, it is not included in any transport layer pseudo- as noted above, it is not included in any transport layer pseudo-
header checksums nor in IPsec authentication [RFC4302]. Both RFC header checksums nor in IPsec authentication [RFC4302]. Both RFC
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there is no reason to expect operational difficulties if a careful there is no reason to expect operational difficulties if a careful
change is made to the rules of RFC 3697. change is made to the rules of RFC 3697.
In particular, the facts that the label is not checksummed and rarely In particular, the facts that the label is not checksummed and rarely
used mean that the current strict immutability of the label can be used mean that the current strict immutability of the label can be
moderated without serious operational consequences. moderated without serious operational consequences.
The purposes of the proposed changes are to remove the uncertainties The purposes of the proposed changes are to remove the uncertainties
left by RFC 3697, in order to encourage setting of the flow label by left by RFC 3697, in order to encourage setting of the flow label by
default, and to enable its generic use. The proposed generic use is default, and to enable its generic use. The proposed generic use is
to encourage pseudo-random flow labels that can be used to assist to encourage uniformly distributed flow labels that can be used to
load distribution balancing. There should be no impact on existing assist load distribution balancing. There should be no impact on
IETF specifications other than RFC 3697 and no impact on currently existing IETF specifications other than RFC 3697 and no impact on
operational software and hardware. currently operational software and hardware.
A secondary purpose is to modify the immutability of the flow label A secondary purpose is to modify the immutability of the flow label
in a limited way, to allow hosts that do not set the flow label to in a limited way, to allow hosts that do not set the flow label to
benefit from it nevertheless. The fact that the flow label may in benefit from it nevertheless. The fact that the flow label may in
practice be changed en route is also reflected in the reformulation practice be changed en route is also reflected in the reformulation
of the rules. of the rules.
A general description of the changes follows. The normative text is A general description of the changes follows. The normative text is
to be found in [I-D.ietf-6man-flow-3697bis]. to be found in [I-D.ietf-6man-flow-3697bis].
The definition of a flow is subtly changed from RFC 3697 to allow any The definition of a flow is subtly changed from RFC 3697 to allow any
node, not just the source node, to set the flow label value. node, not just the source node, to set the flow label value.
However, it is recommended that sources should set a uniformly
However, it is recommended that sources should set a pseudo-random distributed flow label value in all flows, replacing the less precise
flow label value in all flows, replacing the less precise
recommendation made in Section 3 of RFC 3697. Both stateful and recommendation made in Section 3 of RFC 3697. Both stateful and
stateless methods of assigning a pseudo-random value could be used. stateless methods of assigning a uniformly distributed value could be
used.
Flow label values should be chosen such that their bits exhibit a
high degree of variability, making them suitable for use as part of
the input to a hash function used in a load distribution scheme. At
the same time, third parties should be unlikely to be able to guess
the next value that a source of flow labels will choose.
In statistics, a discrete uniform distribution is defined as a
probability distribution in which each value in a given range of
equally spaced values (such as a sequence of integers) is equally
likely to be chosen as the next value. The values in such a
distribution exhibit both variability and unguessability. Thus, an
approximation to a discrete uniform distribution is preferable as the
source of flow label values. In contrast, an implementation in which
flow labels are assigned sequentially is definitely not recommended.
In practice it is expected that a uniform distribution of flow label
values will be approximated by use of a hash function or a pseudo-
random number generator. Either approach will produce values which
will appear pseudo-random to an external observer.
Section 3 of RFC 3697 also allows nodes to participate in an Section 3 of RFC 3697 also allows nodes to participate in an
unspecified method of flow state establishment. The changes do not unspecified stateful method of flow state establishment. The changes
remove that option, but it is made clear that stateless models are do not remove that option, but it is made clear that stateless models
also possible and are the recommended default. The specific text are also possible and are the recommended default. The specific text
about requirements for stateful models has been reduced to a bare about requirements for stateful models has been reduced to a bare
minimum requirement that they do not interfere with the stateless minimum requirement that they do not interfere with the stateless
model. model. To enable stateless load distribution at any point in the
Internet, a network domain using a stateful model should never export
packets originating within the domain whose flow label values do not
conform to a uniform distribution.
The main novelty is that a forwarding node (typically a first-hop or The main novelty is that a forwarding node (typically a first-hop or
ingress router) may set the flow label value if the source has not ingress router) may set the flow label value if the source has not
done so, according to the same recommendations that apply to the done so, according to the same recommendations that apply to the
source. This might place a considerable processing load on ingress source. This might place a considerable processing load on ingress
routers, even if they adopted a stateless method of flow routers, even if they adopted a stateless method of flow
identification and label assignment. identification and label assignment.
The immutability of the flow label, once it has been set, is not The immutability of the flow label, once it has been set, is not
changed. However, some qualifications are placed on this property, changed. However, some qualifications are placed on this property,
to allow for the fact that the flow label is an unprotected field and to allow for the fact that the flow label is an unprotected field and
might be changed undetectably. No Internet-wide mechanism can depend might be changed undetectably. No Internet-wide mechanism can depend
mathematically on immutable flow labels. The new rules require that mathematically on immutable flow labels. The new rules require that
flow labels exported to the Internet should always be either zero or flow labels exported to the Internet should always be either zero or
pseudo-random, but even this cannot be relied on mathematically. Use uniformly distributed, but even this cannot be relied on
cases need to be robust against non-conforming flow label values. mathematically. Use cases need to be robust against non-conforming
This will also enhance compatibility with any legacy hosts that set flow label values. This will also enhance compatibility with any
the flow label according to RFC 2460 or RFC 3697. legacy hosts that set the flow label according to RFC 2460 or RFC
3697.
A complication that led to much discussion is the possibility that
hosts inside a particular domain might use a stateful method of
setting the flow label, and that packets bearing stateful labels
might then erroneously escape the domain and be received by nodes
performing stateless processing such as load balancing. This might
result in undesirable operational implications (e.g., congestion,
reordering) for not only the inappropriately flow-labelled packets,
but also well-behaved flow-labelled packets, during forwarding at
various intermediate devices. It was proposed to suggest that border
routers might "correct" this problem by overwriting such labels in
packets leaving the domain. However, neither domain border egress
routers nor intermediate routers/devices (using a flow label, for
example, as a part of an input key for a load-distribution hash) can
determine by inspection that a value is not part of a uniform
distribution. Therefore, there is no way that such values can be
detected and "corrected".
4. Discussion 4. Discussion
The following are some practical consequences of the above changes: The following are some practical consequences of the above changes:
o Sending hosts that are not updated will in practice continue to o Sending hosts that are not updated will in practice continue to
send all-zero labels. If there is no label-setting router along send all-zero labels. If there is no label-setting router along
the path taken by a packet, the label will be delivered as zero. the path taken by a packet, the label will be delivered as zero.
o Sending hosts conforming to the new specification will by default o Sending hosts conforming to the new specification will by default
choose pseudo-random labels between 1 and 0xFFFFF. choose uniformly distributed labels between 1 and 0xFFFFF.
o Sending hosts may continue to send all-zero labels, in which case o Sending hosts may continue to send all-zero labels, in which case
an ingress router may set pseudo-random labels between 1 and an ingress router may set uniformly distributed labels between 1
0xFFFFF. and 0xFFFFF.
o The flow label is no longer unrealistically asserted to be o The flow label is no longer unrealistically asserted to be
strictly immutable; it is recognised that it may, incorrectly, be strictly immutable; it is recognised that it may, incorrectly, be
changed en route. In some circumstances this will break end-to- changed en route. In some circumstances this will break end-to-
end usage, e.g. potential detection of third-party spoofing end usage, e.g. potential detection of third-party spoofing
attacks [I-D.gont-6man-flowlabel-security]. attacks [I-D.gont-6man-flowlabel-security].
o The expected default usage of the flow label is some form of o The expected default usage of the flow label is some form of
stateless load distribution, such as the ECMP/LAG usage defined in stateless load distribution, such as the ECMP/LAG usage defined in
[I-D.carpenter-flow-ecmp]. [I-D.carpenter-flow-ecmp].
o If the new rules are followed, all IPv6 traffic flows on the o If the new rules are followed, all IPv6 traffic flows on the
Internet should have zero or pseudo-random flow label values. Internet should have zero or uniformly distributed flow label
values.
From an operational viewpoint, existing IPv6 hosts that set a default From an operational viewpoint, existing IPv6 hosts that set a default
(zero) flow label value and ignore the flow label on receipt will be (zero) flow label value and ignore the flow label on receipt will be
unaffected by implementations of the new specification. In general, unaffected by implementations of the new specification. In general,
it is assumed that hosts will ignore the value of the flow label on it is assumed that hosts will ignore the value of the flow label on
receipt; it cannot be relied on as an end-to-end signal. However, receipt; it cannot be relied on as an end-to-end signal. However,
this doesn't apply if a cryptographically generated label is being this doesn't apply if a cryptographically generated label is being
used to detect attackers [I-D.gont-6man-flowlabel-security]. used to detect attackers [I-D.gont-6man-flowlabel-security].
Similarly, routers that ignore the flow label will be unaffected by Similarly, routers that ignore the flow label will be unaffected by
implementations of the specification. implementations of the specification.
Hosts that set a default (zero) flow label but are in a domain where Hosts that set a default (zero) flow label but are in a domain where
routers set a pseudo-random label as recommended in Section 3 will routers set a label as recommended in Section 3 will benefit from
benefit from whatever flow label handling is used on the path. whatever flow label handling is used on the path.
Hosts and routers that adopt the recommended pseudo-random mechanism Hosts and routers that adopt the recommended mechanism will enhance
will enhance the performance of any load balancing devices that the performance of any load balancing devices that include the flow
include the flow label in the hash used to select a particular path label in the hash used to select a particular path or server, even
or server, even when packets leave the local domain. when packets leave the local domain.
5. Security Considerations 5. Security Considerations
See [I-D.ietf-6man-flow-3697bis] and See [I-D.ietf-6man-flow-3697bis] and
[I-D.gont-6man-flowlabel-security] for full discussion. [I-D.gont-6man-flowlabel-security] for full discussion.
6. IANA Considerations 6. IANA Considerations
This document requests no action by IANA. This document requests no action by IANA.
skipping to change at page 9, line 7 skipping to change at page 10, line 5
The authors are grateful to Qinwen Hu for general discussion about The authors are grateful to Qinwen Hu for general discussion about
the flow label and for his work in searching the literature. the flow label and for his work in searching the literature.
Valuable comments and contributions were made by Fred Baker, Steve Valuable comments and contributions were made by Fred Baker, Steve
Blake, Remi Despres, Alan Ford, Fernando Gont, Brian Haberman, Tony Blake, Remi Despres, Alan Ford, Fernando Gont, Brian Haberman, Tony
Hain, Joel Halpern, Chris Morrow, Thomas Narten, Pekka Savola, Mark Hain, Joel Halpern, Chris Morrow, Thomas Narten, Pekka Savola, Mark
Smith, Pascal Thubert, Iljitsch van Beijnum, and other participants Smith, Pascal Thubert, Iljitsch van Beijnum, and other participants
in the 6man working group. in the 6man working group.
This document was produced using the xml2rfc tool [RFC2629]. This document was produced using the xml2rfc tool [RFC2629].
8. Change log 8. Change log [RFC Editor: please remove]
draft-ietf-6man-flow-update-04: updated again to be in styep with RFC draft-ietf-6man-flow-update-05: updated again to be in step with RFC
3697bis, 2011-05-02
draft-ietf-6man-flow-update-04: updated again to be in step with RFC
3697bis, 2011-03-13 3697bis, 2011-03-13
draft-ietf-6man-flow-update-03: updated to be in styep with RFC draft-ietf-6man-flow-update-03: updated to be in step with RFC
3697bis, 2011-02-26 3697bis, 2011-02-26
draft-ietf-6man-flow-update-02: repurposed as rationale for update of draft-ietf-6man-flow-update-02: repurposed as rationale for update of
RFC 3697, 2011-01-31 RFC 3697, 2011-01-31
draft-ietf-6man-flow-update-01: clarified that this is not a formal draft-ietf-6man-flow-update-01: clarified that this is not a formal
update of RFC 3697, clarified text about domains exporting update of RFC 3697, clarified text about domains exporting
inappropriate labels, 2011-01-10 inappropriate labels, 2011-01-10
draft-ietf-6man-flow-update-00: adopted as WG document at IETF 79, draft-ietf-6man-flow-update-00: adopted as WG document at IETF 79,
skipping to change at page 10, line 13 skipping to change at page 11, line 13
November 2010. November 2010.
[I-D.hu-flow-label-cases] [I-D.hu-flow-label-cases]
Hu, Q. and B. Carpenter, "Survey of proposed use cases for Hu, Q. and B. Carpenter, "Survey of proposed use cases for
the IPv6 flow label", draft-hu-flow-label-cases-03 (work the IPv6 flow label", draft-hu-flow-label-cases-03 (work
in progress), February 2011. in progress), February 2011.
[I-D.ietf-6man-flow-3697bis] [I-D.ietf-6man-flow-3697bis]
Amante, S., Carpenter, B., Jiang, S., and J. Rajahalme, Amante, S., Carpenter, B., Jiang, S., and J. Rajahalme,
"IPv6 Flow Label Specification", "IPv6 Flow Label Specification",
draft-ietf-6man-flow-3697bis-01 (work in progress), draft-ietf-6man-flow-3697bis-02 (work in progress),
February 2011. March 2011.
[I-D.martinbeckman-ietf-ipv6-fls-ipv6flowswitching] [I-D.martinbeckman-ietf-ipv6-fls-ipv6flowswitching]
Beckman, M., "IPv6 Dynamic Flow Label Switching (FLS)", Beckman, M., "IPv6 Dynamic Flow Label Switching (FLS)",
draft-martinbeckman-ietf-ipv6-fls-ipv6flowswitching-03 draft-martinbeckman-ietf-ipv6-fls-ipv6flowswitching-03
(work in progress), March 2007. (work in progress), March 2007.
[McGann05] [McGann05]
McGann, O. and D. Malone, "Flow Label Filtering McGann, O. and D. Malone, "Flow Label Filtering
Feasibility", European Conference on Computer Network Feasibility", European Conference on Computer Network
Defence , 2005. Defence , 2005.
 End of changes. 26 change blocks. 
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