IPv6 Operations Working Group (v6ops) F. Gont
Internet-Draft SI6 Networks / UTN-FRH
Intended status: Informational N. Hilliard
Expires: August 7, 2016 INEX
G. Doering
SpaceNet AG
W. Liu
Huawei Technologies
W. Kumari
Google
February 4, 2016
Operational Implications of IPv6 Packets with Extension Headers
draft-gont-v6ops-ipv6-ehs-packet-drops-02
Abstract
This document summarizes the security and operational implications of
IPv6 extension headers, and attempts to analyze reasons why packets
with IPv6 extension headers may be dropped in the public Internet.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
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This Internet-Draft will expire on August 7, 2016.
Copyright Notice
Copyright (c) 2016 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
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carefully, as they describe your rights and restrictions with respect
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Previous Work on IPv6 Extension Headers . . . . . . . . . . . 3
3. Security Implications . . . . . . . . . . . . . . . . . . . . 3
4. Operational Implications . . . . . . . . . . . . . . . . . . 5
4.1. Requirement to process required layer-3/layer-4
information . . . . . . . . . . . . . . . . . . . . . . . 5
4.2. Route-Processor Protection . . . . . . . . . . . . . . . 7
4.3. Inability to Perform Fine-grained Filtering . . . . . . . 8
5. A Possible Attack Vector . . . . . . . . . . . . . . . . . . 8
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
7. Security Considerations . . . . . . . . . . . . . . . . . . . 10
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 10
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 10
9.1. Normative References . . . . . . . . . . . . . . . . . . 10
9.2. Informative References . . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
1. Introduction
IPv6 Extension Headers (EHs) allow for the extension of the IPv6
protocol, and provide support for core functionality such as IPv6
fragmentation. However, common implementation limitations suggest
that EHs present a challenge for IPv6 packet routing equipment, and
evidence exists to suggest that IPv6 packets with EHs may be
intentionally dropped on the public Internet in some network
deployments.
The authors of this document have been involved in numerous
discussions about IPv6 extension headers (both within the IETF and
outside of it), and have noticed that a number of security and
operational issues were unknown to the larger audience participating
in these discussions.
This document has the following goals:
o Raise awareness about the security and operational implications of
IPv6 Extension Headers, and presents reason why some networks
intentionally drop packets containing IPv6 Extension Headers.
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o Highlight areas where current IPv6 support by networking devices
maybe sub-optimal, such that the aforementioned support is
improved.
o Highlight operational issues associated with IPv6 extension
headers, such that those issues are considered in IETF
standardization efforts.
Section 2 of this document summarizes the previous work that has been
done in the area of IPv6 extension headers. Section 3 briefly
discusses the security implications of IPv6 Extension Headers, while
Section 4 discusses their operational implications.
2. Previous Work on IPv6 Extension Headers
Some of the implications of IPv6 Extension Headers have been
discussed in IETF circles. For example, [I-D.taylor-v6ops-fragdrop]
discusses a rationale for which operators drop IPv6 fragments.
[I-D.wkumari-long-headers] discusses possible issues arising from
"long" IPv6 header chains. [RFC7045] clarifies how intermediate
nodes should deal with IPv6 extension headers. [RFC7112] discusses
the issues arising in a specific fragmentation case where the IPv6
header chain is fragmented into two or more fragments (and formally
forbids such fragmentation case).
[I-D.kampanakis-6man-ipv6-eh-parsing] describes how inconsistencies
in the way IPv6 packets with extension headers are parsed by
different implementations may result in evasion of security controls,
and presents guidelines for parsing IPv6 extension headers with the
goal of providing a common and consistent parsing methodology for
IPv6 implementations. [RFC6980] analyzes the security implications
of employing IPv6 fragmentation with Neighbor Discovery for IPv6, and
formally recommends against such usage. Finally, [RFC7123] discusses
how some popular RA-Guard implementations are subject to evasion by
means of IPv6 extension headers.
Some preliminary measurements regarding the extent to which packet
containing IPv6 EHs are dropped in the public Internet have been
presented in [PMTUD-Blackholes], [Gont-IEPG88], [Gont-Chown-IEPG89],
and [Linkova-Gont-IEPG90]. [I-D.ietf-v6ops-ipv6-ehs-in-real-world]
presents more comprehensive results and documents the methodology for
obtaining the presented results.
3. Security Implications
The security implications of IPv6 Extension Headers generally fall
into one or more of these categories:
o Evasion of security controls
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o DoS due to processing requirements
o DoS due to implementation errors
o Extension Header-specific issues
Unlike IPv4 packets where the upper-layer protocols can be trivially
found by means of the "IHL" ("Internet Header Length") IPv4 header
field, the structure of IPv6 packets is more flexible and complex.
Locating upper-layer protocol information requires that all IPv6
extension headers be examined. This has presented implementation
difficulties, and packet filtering mechanisms that require upper-
layer information (even if just the upper layer protocol type) on
several security devices can be trivially evaded by inserting IPv6
Extension Headers between the main IPv6 header and the upper layer
protocol. [RFC7113] describes this issue for the RA-Guard case, but
the same techniques can be employed to circumvent other IPv6 firewall
and packet filtering mechanisms. Additionally, implementation
inconsistencies in packet forwarding engines may result in evasion of
security controls [I-D.kampanakis-6man-ipv6-eh-parsing] [Atlasis2014]
[BH-EU-2014].
Packets that use IPv6 Extension Headers may have a negative
performance impact on the handling devices. Unless appropriate
mitigations are put in place (e.g., packet dropping and/or rate-
limiting), an attacker could simply send a large amount of IPv6
traffic employing IPv6 Extension Headers with the purpose of
performing a Denial of Service (DoS) attack (see Section 4 for
further details).
NOTE:
In the most trivial case, a packet that includes a Hop-by-Hop
Options header will typically go through the slow forwarding path,
and be processed by the router's CPU. Another possible case might
be that in which a router that has been configured to enforce an
ACL based on upper-layer information (e.g., upper layer protocol
or TCP Destination Port), needs to process the entire IPv6 header
chain (in order to find the required information) and this causes
the packet to be processed in the slow path [Cisco-EH-Cons]. We
note that, for obvious reasons, the aforementioned performance
issues may also affect other devices such as firewalls, Network
Intrusion Detection Systems (NIDS), etc. [Zack-FW-Benchmark].
The extent to which these devices are affected will typically be
implementation-dependent.
IPv6 implementations, like all other software, tend to mature with
time and wide-scale deployment. While the IPv6 protocol itself has
existed for almost 20 years, serious bugs related to IPv6 Extension
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Header processing continue to be discovered. Because there is
currently little operational reliance on IPv6 Extension headers, the
corresponding code paths are rarely exercised, and there is the
potential that bugs still remain to be discovered in some
implementations.
IPv6 Fragment Headers are employed to allow fragmentation of IPv6
packets. While many of the security implications of the
fragmentation / reassembly mechanism are known from the IPv4 world,
several related issues have crept into IPv6 implementations. These
range from denial of service attacks to information leakage, for
example [I-D.ietf-6man-predictable-fragment-id], [Bonica-NANOG58] and
[Atlasis2012]).
4. Operational Implications
4.1. Requirement to process required layer-3/layer-4 information
Intermediate systems and middleboxes that need to find the layer-4
header must process the entire IPv6 extension header chain. When
such devices are unable to obtain the required information, they may
simply drop the corresponding packets. The following subsections
discuss some of reasons for which such layer-4 information may be
needed by an intermediate systems or middlebox, and why packets
containing IPv6 extension headers may represent a challenge in such
scenarios.
4.1.1. Packet Forwarding Engine Constraints
Most modern routers use dedicated hardware (e.g. ASICs or NPUs) to
determine how to forward packets across their internal fabrics (see
[IEPG94-Scudder] for details). One of the common methods of handling
next-hop lookup is to send a small portion of the ingress packet to a
lookup engine with specialised hardware (e.g. ternary CAM or RLDRAM)
to determine the packet's next-hop. Technical constraints mean that
there is a trade-off between the amount of data sent to the lookup
engine and the overall performance of the lookup engine. If more
data is sent, the lookup engine can inspect further into the packet,
but the overall performance of the system will be reduced. If less
data is sent, the overall performance of the router will be increased
but the packet lookup engine may not be able to inspect far enough
into a packet to determine how it should be handled.
NOTE:
For example, current high-end routers at the time of authorship of
this document can use up to 192 bytes of header (Cisco ASR9000
Typhoon) or 384 bytes of header (Juniper MX Trio)
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If a hardware forwarding engine on a modern router cannot make a
forwarding decision about a packet because critical information is
not sent to the look-up engine, then the router will normally drop
the packet. Historically, some packet forwarding engines punted
packets of this form to the control plane for more in-depth analysis,
but this is unfeasible on most current router architectures as a
result of the vast difference between the hardware forwarding
capacity of the router and processing capacity of the control plane
and the size of the management link which connects the control plane
to the forwarding plane.
If an IPv6 header chain is sufficiently long that its header exceeds
the packet look-up capacity of the router, then it may be dropped due
to hardware inability to determine how it should be handled.
4.1.2. ECMP and Hash-based Load-Sharing
In the case of ECMP (equal cost multi path) load sharing, the router
on the sending side of the link needs to make a decision regarding
which of the links to use for a given packet. Since round-robin
usage of the links is usually avoided in order to prevent packet
reordering, forwarding engines need to use a mechanism which will
consistently forward the same data streams down the same forwarding
paths. Most forwarding engines achieve this by calculating a simple
hash using an n-tuple gleaned from a combination of layer-2 through
to layer-4 packet header information. This n-tuple will typically
use the src/dst MAC address, src/dst IP address, and if possible
further layer-4 src/dst port information. As layer-4 port
information increases the entropy of the hash, it is highly desirable
to use it where possible.
We note that in the IPv6 world, flows are expected to be identified
by means of the IPv6 Flow Label [RFC6437]. Thus, ECMP and Hash-based
Load-Sharing would be possible without the need to process the entire
IPv6 header chain to obtain upper-layer information to identify
flows. However, we note that for a long time many IPv6
implementations failed to set the Flow Label, and ECMP and Hash-based
Load-Sharing devices also did not employ the Flow Label for
performing their task.
Clearly, widespread support of [RFC6437] would relieve middle-boxes
from having to process the entire IPv6 header chain, making Flow
Label-based ECMP and Hash-based Load-Sharing [RFC6438] feasible.
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4.1.3. Enforcing infrastructure ACLs
Generally speaking, infrastructure ACLs (iACLs) drop unwanted packets
destined to parts of a provider's infrastructure, because they are
not operationally needed and can be used for attacks of different
sorts against the router's control plane. Some traffic needs to be
differentiated depending on layer-3 or layer-4 criteria to achieve a
useful balance of protection and functionality, for example:
o Permit some amount of ICMP echo (ping) traffic towards the
router's addresses for troubleshooting.
o Permit BGP sessions on the shared network of an exchange point
(potentially differentiating between the amount of packets/seconds
permitted for established sessions and connection establishment),
but do not permit other traffic from the same peer IP addresses.
4.1.4. DDoS Management and Customer Requests for Filtering
The case of customer DDoS protection and edge-to-core customer
protection filters is similar in nature to the infrastructure ACL
protection. Similar to infrastructure ACL protection, layer-4 ACLs
generally need to be applied as close to the edge of the network as
possible, even though the intent is usually to protect the customer
edge rather than the provider core. Application of layer-4 DDoS
protection to a network edge is often automated using Flowspec
[RFC5575].
For example, a web site which normally only handled traffic on TCP
ports 80 and 443 could be subject to a volumetric DDoS attack using
NTP and DNS packets with randomised source IP address, thereby
rendering useless traditional [RFC5635] source-based real-time black
hole mechanisms. In this situation, DDoS protection ACLs could be
configured to block all UDP traffic at the network edge without
impairing the web server functionality in any way. Thus, being able
to block arbitrary protocols at the network edge can avoid DDoS-
related problems both in the provider network and on the customer
edge link.
4.2. Route-Processor Protection
Most modern routers have a fast hardware-assisted forwarding plane
and a loosely coupled control plane, connected together with a link
that has much less capacity than the forwarding plane could handle.
Traffic differentiation cannot be done by the control plane side,
because this would overload the internal link connecting the
forwarding plane to the control plane.
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The Hop-by-Hop Options header is particularly challenging since, in
most (if not all) implementations, it causes the corresponding packet
to be punted to a software path. As a result, operators usually drop
IPv6 packets containing this extension header. Please see [RFC6192]
for advice regarding protection of the router control plane.
4.3. Inability to Perform Fine-grained Filtering
Some routers lack of fine-grained filtering of IPv6 extension
headers. For example, an operator may want to drop packets
containing Routing Header Type 0 (RHT0) but may only be able to
filter on the extension header type (Routing Header). As a result,
the operator may end up enforcing a more coarse filtering policy
(e.g. "drop all packets containing a Routing Header" vs. "only drop
packets that contain a Routing Header Type 0").
5. A Possible Attack Vector
The widespread drop of IPv6 packets employing IPv6 Extension Headers
can, in some scenarios, be exploited for malicious purposes: if
packets employing IPv6 EHs are known to be dropped on the path from
system A to system B, an attacker could cause packets sent from A to
B to be dropped by sending a forged ICMPv6 Packet Too Big (PTB)
[RFC4443] error message to A (advertising an MTU smaller than 1280),
such that subsequent packets from A to B include a fragment header
(i.e., they result in atomic fragments [RFC6946]).
Possible scenarios where this attack vector could be exploited
include (but are not limited to):
o Communication between any two systems through the public network
(e.g., client from/to server or server from/to server), where
packets with IPv6 extension headers are dropped by some
intermediate router
o Communication between two BGP peers employing IPv6 transport,
where these BGP peers implement ACLs to drop IPv6 fragments (to
avoid control-plane attacks)
The aforementioned attack vector is exacerbated by the following
factors:
o The attacker does not need to forge the IPv6 Source Address of his
attack packets. Hence, deployment of simple BCP38 filters will
not help as a counter-measure.
o Only the IPv6 addresses of the IPv6 packet embedded in the ICMPv6
payload need to be forged. While one could envision filtering
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devices enforcing BCP38-style filters on the ICMPv6 payload, the
use of extension headers (by the attacker) could make this
difficult, if not impossible.
o Many implementations fail to perform validation checks on the
received ICMPv6 error messages, as recommended in Section 5.2 of
[RFC4443] and documented in [RFC5927]. It should be noted that in
some cases, such as when an ICMPv6 error message has (supposedly)
been elicited by a connection-less transport protocol (or some
other connection-less protocol being encapsulated in IPv6), it may
be virtually impossible to perform validation checks on the
received ICMPv6 error messages. And, because of IPv6 extension
headers, the ICMPv6 payload might not even contain any useful
information on which to perform validation checks.
o Upon receipt of one of the aforementioned ICMPv6 "Packet Too Big"
error messages, the Destination Cache [RFC4861] is usually updated
to reflect that any subsequent packets to such destination should
include a Fragment Header. This means that a single ICMPv6
"Packet Too Big" error message might affect multiple communication
instances (e.g. TCP connections) with such destination.
o A router or other middlebox cannot simply drop all incoming ICMPv6
Packet Too Big error messages, as this would create a PMTUD
blackhole.
Possible mitigations for this issue include:
o Dropping incoming ICMPv6 Packet Too Big error messages that
advertise an MTU smaller than 1280 bytes.
o Artificially reducing the MTU to 1280 bytes and dropping incoming
ICMPv6 PTB error messages.
Both of these mitigations come at the expense of possibly preventing
communication through SIIT [RFC6145], that relies on IPv6 atomic
fragments (see [I-D.ietf-6man-deprecate-atomfrag-generation]), and
also implies that the filtering device has the ability to filter ICMP
PTB messages based on the contents of the MTU field.
[I-D.ietf-6man-deprecate-atomfrag-generation] documents while the
generation of IPv6 atomic fragments is considered harmful, and
documents why this functionality is being removed from the upcoming
revision of the core IPv6 protocol [I-D.ietf-6man-rfc2460bis]. Thus,
any of the above mitigations would eliminate the attack vector
without any interoperability implications.
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6. IANA Considerations
There are no IANA registries within this document. The RFC-Editor
can remove this section before publication of this document as an
RFC.
7. Security Considerations
The security implications of IPv6 extension headers are discussed in
Section 3. A specific attack vector that could leverage the
widespread dropping of packets with IPv6 EHs (along with possible
countermeasures) is discussed in Section 5. This document does not
introduce any new security issues.
8. Acknowledgements
The authors would like to thank (in alphabetical order) Mikael
Abrahamsson, Brian Carpenter, Sander Steffann, Eric Vyncke, and
Andrew Yourtchenko, for providing valuable comments on earlier
versions of this document. Additionally, the authors would like to
thank participants of the v6ops working group for their valuable
input on the topics that led to the publication of this document.
Fernando Gont would like to thank Sander Steffann, who took the time
to meet to discuss this document, even while higher priority events
were in place.
Fernando Gont would like to thank Jan Zorz / Go6 Lab
, and Jared Mauch / NTT America, for providing
access to systems and networks that were employed to perform
experiments and measurements involving packets with IPv6 Extension
Headers. Additionally, he would like to thank SixXS
for providing IPv6 connectivity.
9. References
9.1. Normative References
[RFC2460] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", RFC 2460, DOI 10.17487/RFC2460,
December 1998, .
[RFC4443] Conta, A., Deering, S., and M. Gupta, Ed., "Internet
Control Message Protocol (ICMPv6) for the Internet
Protocol Version 6 (IPv6) Specification", RFC 4443,
DOI 10.17487/RFC4443, March 2006,
.
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[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
"Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
DOI 10.17487/RFC4861, September 2007,
.
[RFC6145] Li, X., Bao, C., and F. Baker, "IP/ICMP Translation
Algorithm", RFC 6145, DOI 10.17487/RFC6145, April 2011,
.
[RFC6946] Gont, F., "Processing of IPv6 "Atomic" Fragments",
RFC 6946, DOI 10.17487/RFC6946, May 2013,
.
9.2. Informative References
[Atlasis2012]
Atlasis, A., "Attacking IPv6 Implementation Using
Fragmentation", BlackHat Europe 2012. Amsterdam,
Netherlands. March 14-16, 2012,
.
[Atlasis2014]
Atlasis, A., "A Novel Way of Abusing IPv6 Extension
Headers to Evade IPv6 Security Devices", May 2014,
.
[BH-EU-2014]
Atlasis, A., Rey, E., and R. Schaefer, "Evasion of High-
End IDPS Devices at the IPv6 Era", BlackHat Europe 2014,
2014, .
[Bonica-NANOG58]
Bonica, R., "IPv6 Extension Headers in the Real World
v2.0", NANOG 58. New Orleans, Louisiana, USA. June 3-5,
2013, .
[Cisco-EH-Cons]
Cisco, , "IPv6 Extension Headers Review and
Considerations", October 2006,
.
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[Gont-Chown-IEPG89]
Gont, F. and T. Chown, "A Small Update on the Use of IPv6
Extension Headers", IEPG 89. London, UK. March 2, 2014,
.
[Gont-IEPG88]
Gont, F., "Fragmentation and Extension header Support in
the IPv6 Internet", IEPG 88. Vancouver, BC, Canada.
November 13, 2013, .
[I-D.ietf-6man-deprecate-atomfrag-generation]
Gont, F., LIU, S., and T. Anderson, "Generation of IPv6
Atomic Fragments Considered Harmful", draft-ietf-6man-
deprecate-atomfrag-generation-05 (work in progress),
January 2016.
[I-D.ietf-6man-predictable-fragment-id]
Gont, F., "Security Implications of Predictable Fragment
Identification Values", draft-ietf-6man-predictable-
fragment-id-10 (work in progress), October 2015.
[I-D.ietf-6man-rfc2460bis]
Deering, S. and B. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", draft-ietf-6man-rfc2460bis-03 (work
in progress), January 2016.
[I-D.ietf-v6ops-ipv6-ehs-in-real-world]
Gont, F., Linkova, J., Chown, T., and S. LIU,
"Observations on the Dropping of Packets with IPv6
Extension Headers in the Real World", draft-ietf-v6ops-
ipv6-ehs-in-real-world-02 (work in progress), December
2015.
[I-D.kampanakis-6man-ipv6-eh-parsing]
Kampanakis, P., "Implementation Guidelines for parsing
IPv6 Extension Headers", draft-kampanakis-6man-ipv6-eh-
parsing-01 (work in progress), August 2014.
[I-D.taylor-v6ops-fragdrop]
Jaeggli, J., Colitti, L., Kumari, W., Vyncke, E., Kaeo,
M., and T. Taylor, "Why Operators Filter Fragments and
What It Implies", draft-taylor-v6ops-fragdrop-02 (work in
progress), December 2013.
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[I-D.wkumari-long-headers]
Kumari, W., Jaeggli, J., Bonica, R., and J. Linkova,
"Operational Issues Associated With Long IPv6 Header
Chains", draft-wkumari-long-headers-03 (work in progress),
June 2015.
[IEPG94-Scudder]
Petersen, B. and J. Scudder, "Modern Router Architecture
for Protocol Designers", IEPG 94. Yokohama, Japan.
November 1, 2015, .
[Linkova-Gont-IEPG90]
Linkova, J. and F. Gont, "IPv6 Extension Headers in the
Real World v2.0", IEPG 90. Toronto, ON, Canada. July 20,
2014, .
[PMTUD-Blackholes]
De Boer, M. and J. Bosma, "Discovering Path MTU black
holes on the Internet using RIPE Atlas", July 2012,
.
[RFC5575] Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J.,
and D. McPherson, "Dissemination of Flow Specification
Rules", RFC 5575, DOI 10.17487/RFC5575, August 2009,
.
[RFC5635] Kumari, W. and D. McPherson, "Remote Triggered Black Hole
Filtering with Unicast Reverse Path Forwarding (uRPF)",
RFC 5635, DOI 10.17487/RFC5635, August 2009,
.
[RFC5927] Gont, F., "ICMP Attacks against TCP", RFC 5927,
DOI 10.17487/RFC5927, July 2010,
.
[RFC6192] Dugal, D., Pignataro, C., and R. Dunn, "Protecting the
Router Control Plane", RFC 6192, DOI 10.17487/RFC6192,
March 2011, .
[RFC6437] Amante, S., Carpenter, B., Jiang, S., and J. Rajahalme,
"IPv6 Flow Label Specification", RFC 6437,
DOI 10.17487/RFC6437, November 2011,
.
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[RFC6438] Carpenter, B. and S. Amante, "Using the IPv6 Flow Label
for Equal Cost Multipath Routing and Link Aggregation in
Tunnels", RFC 6438, DOI 10.17487/RFC6438, November 2011,
.
[RFC6980] Gont, F., "Security Implications of IPv6 Fragmentation
with IPv6 Neighbor Discovery", RFC 6980,
DOI 10.17487/RFC6980, August 2013,
.
[RFC7045] Carpenter, B. and S. Jiang, "Transmission and Processing
of IPv6 Extension Headers", RFC 7045,
DOI 10.17487/RFC7045, December 2013,
.
[RFC7112] Gont, F., Manral, V., and R. Bonica, "Implications of
Oversized IPv6 Header Chains", RFC 7112,
DOI 10.17487/RFC7112, January 2014,
.
[RFC7113] Gont, F., "Implementation Advice for IPv6 Router
Advertisement Guard (RA-Guard)", RFC 7113,
DOI 10.17487/RFC7113, February 2014,
.
[RFC7123] Gont, F. and W. Liu, "Security Implications of IPv6 on
IPv4 Networks", RFC 7123, DOI 10.17487/RFC7123, February
2014, .
[RIPE-Atlas]
RIPE, , "RIPE Atlas", .
[Zack-FW-Benchmark]
Zack, E., "Firewall Security Assessment and Benchmarking
IPv6 Firewall Load Tests", IPv6 Hackers Meeting #1,
Berlin, Germany. June 30, 2013,
.
Authors' Addresses
Gont, et al. Expires August 7, 2016 [Page 14]
Internet-Draft IPv6 Extension Headers February 2016
Fernando Gont
SI6 Networks / UTN-FRH
Evaristo Carriego 2644
Haedo, Provincia de Buenos Aires 1706
Argentina
Phone: +54 11 4650 8472
Email: fgont@si6networks.com
URI: http://www.si6networks.com
Nick Hilliard
INEX
4027 Kingswood Road
Dublin 24
IE
Email: nick@inex.ie
Gert Doering
SpaceNet AG
Joseph-Dollinger-Bogen 14
Muenchen D-80807
Germany
Email: gert@space.net
Will (Shucheng) Liu
Huawei Technologies
Bantian, Longgang District
Shenzhen 518129
P.R. China
Email: liushucheng@huawei.com
Warren Kumari
Google
1600 Amphitheatre Parkway
Mountain View, CA 94043
US
Email: warren@kumari.net
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