IPv6 Packet Truncation
draft-leddy-6man-truncate-04
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draft-leddy-6man-truncate-04
6man J. Leddy
Internet-Draft Comcast
Intended status: Standards Track R. Bonica
Expires: December 31, 2018 Juniper Networks
June 29, 2018
IPv6 Packet Truncation
draft-leddy-6man-truncate-04
Abstract
This document defines IPv6 packet truncation procedures. When an
IPv6 source node originates a packet, it can mark the packet as being
eligible for truncation and forward it towards its destination. If
an intermediate node cannot forward the packet because of an MTU
issue, it truncates the packet, marks it as being truncated, and,
again, forwards it towards its destination. When the destination
node receives the packet, it detects that it has been truncated and
sends an ICMP message to the source node. The ICMP message contains
MTU information that the source node uses to update its Path MTU
estimate.
The above-mentioned procedures enhance Path MTU Discovery (PMTUD) by
eliminating its reliance on the network's ability to deliver ICMP
messages from an intermediate node to the source node. However, the
above-mentioned procedures require the network to deliver ICMP
messages from the destination node to the source node.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on December 31, 2018.
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Copyright Notice
Copyright (c) 2018 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
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Requirements Language . . . . . . . . . . . . . . . . . . . . 4
3. Operational Considerations . . . . . . . . . . . . . . . . . 5
4. Reference Topology . . . . . . . . . . . . . . . . . . . . . 5
5. New IPv6 Destination Options . . . . . . . . . . . . . . . . 6
5.1. The IPv6 Truncation Eligible Option . . . . . . . . . . . 6
5.2. The IPv6 Truncated Packet Option . . . . . . . . . . . . 7
6. PMTU Signaling Procedures . . . . . . . . . . . . . . . . . . 8
7. Truncation Considerations . . . . . . . . . . . . . . . . . . 9
8. Destination Node Considerations . . . . . . . . . . . . . . . 10
9. Backward Compatibility . . . . . . . . . . . . . . . . . . . 10
10. Optimizations . . . . . . . . . . . . . . . . . . . . . . . . 11
11. Upper-Layer Considerations . . . . . . . . . . . . . . . . . 11
12. Encapsulating Security Payload Considerations . . . . . . . . 11
13. Extension Header Considerations . . . . . . . . . . . . . . . 12
14. Security Considerations . . . . . . . . . . . . . . . . . . . 12
15. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
16. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 13
17. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
17.1. Normative References . . . . . . . . . . . . . . . . . . 13
17.2. Informative References . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
1. Introduction
An Internet path connects a source node to a destination node. A
path can contain links and intermediate nodes (e.g., routers).
Each link is constrained by the number of bytes that it can convey in
a single IP packet. This constraint is called the link Maximum
Transmission Unit (MTU). IPv6 [RFC8200] requires every link to have
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an MTU of 1280 bytes or greater. This value is called IPv6 minimum
link MTU.
Likewise, each Internet path is constrained by the number of bytes
that it can convey in a IP single packet. This constraint is called
the Path MTU (PMTU). For any given path, the PMTU is equal to the
smallest of its link MTUs.
IPv6 allows fragmentation at the source node only. If an IPv6 source
node sends a packet whose length exceeds the PMTU, an intermediate
node will discard the packet. In order to prevent this, IPv6 nodes
can either:
o Refrain from sending packets whose length exceeds the IPv6 minimum
link MTU.
o Maintain a running estimate of the PMTU and refrain from sending
packets whose length exceeds that estimate.
IPv6 nodes can execute Path MTU Discovery (PMTUD) [RFC8201]
procedures in order to maintain a running estimate of the PMTU.
According to these procedures, the source node produces an initial
PMTU estimate. This initial estimate is equal to the MTU of the
first link along the path to the destination. It can be greater than
the actual PMTU.
Having produced an initial PMTU estimate, the source node sends
packets to the destination node. If one of these packets is larger
than the actual PMTU, an intermediate node will not be able to
forward the packet through the next link along the path. Therefore,
the intermediate node discards the packet and sends an Internet
Control Message Protocol (ICMP) [RFC4443] Packet Too Big (PTB)
message to the source node. The ICMP PTB message indicates the MTU
of the link through which the packet could not be forwarded. The
source node uses this information to refine its PMTU estimate.
PMTUD relies on the network's ability to deliver ICMP PTB messages
from the intermediate node to the source node. If the network cannot
deliver these messages, a persistent black hole can develop. In this
scenario, the source node sends a packet whose length exceeds the
PMTU. An intermediate node discards the packet and sends an ICMP PTB
message to the source. However, the network cannot deliver the ICMP
PTB message to the source. Therefore, the source node does not
update its PMTU estimate and it continues to send packets whose
length exceeds the PMTU. The intermediate node discards these
packets and sends more ICMP PTB messages to the source. These ICMP
PTB messages are lost, exactly as previous ICMP PTB messages were
lost.
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In some operational scenarios (Section 3), networks cannot deliver
ICMP PTB messages from an intermediate node to the source node.
Therefore, enhanced procedures are required.
This document defines IPv6 packet truncation procedures. When an
IPv6 source node originates a packet, it can mark the packet as being
eligible for truncation and forward it towards its destination. If
an intermediate node cannot forward the packet because of an MTU
issue, it truncates the packet, marks it as being truncated, and,
again, forwards it towards its destination. When the destination
node receives the packet, it detects that it has been truncated and
sends an ICMP message to the source node. The ICMP message contains
MTU information that the source node uses to update its Path MTU
estimate.
The above-mentioned procedures enhance PMTUD by eliminating its
reliance on the network's ability to deliver ICMP messages from an
intermediate node to the source node. However, the above-mentioned
procedures require the network to deliver ICMP messages from the
destination node to the source node.
By default, destination nodes discard truncated packets and do not
deliver them to upper-layer protocols. However, upper-layer
protocols can register for delivery of truncated packets. When an
upper-layer protocol receives a truncated packet, it can infer the
PMTU between the source node and itself from the packet's length.
Having inferred the PMTU, the upper-layer protocol can negotiate a
maximum packet size with its upper-layer peer, thus reducing its
reliance upon PMTUD and IPv6 fragmentation.
While IPv6 packet truncation may facilitate new upper-layer
procedures, upper-layer procedures are beyond the scope of this
document. In particular, this document does not address the behavior
of upper-layer protocols that register for delivery of truncated
packets.
2. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
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3. Operational Considerations
The packet truncation procedures described herein make PMTUD more
resilient when:
o The network can deliver ICMP messages from the destination node to
the source node.
o The network cannot deliver ICMP messages from an intermediate node
to the source node.
The following are operational scenarios in which packet truncation
procedures can make PMTUD more resilient:
o The destination node has a viable route to the source node, but
the intermediate node does not.
o The source node is protected by a firewall that administratively
blocks all packets except for those from specified subnetworks.
The destination node resides in one of the specified subnetworks,
but the intermediate node does not.
o The source address of the original packet (i.e., the packet that
elicited the ICMP message) was an anycast address. Therefore, the
destination address of the ICMP message is the same anycast
address. In this case, an ICMP message from the destination node
is likely to be delivered to the correct anycast instance. By
contrast, an ICMP message from an intermediate node is less likely
to be delivered to the correct anycast instance.
Packet truncation procedures do not make PMTUD more resilient when
the network cannot reliably deliver any ICMP messages to the source
node. The following are operational scenarios where the network
cannot reliably deliver any ICMP PTB messages to the source node:
o The source node is protected by a firewall that administratively
blocks all ICMP messages.
o The source node is an anycast instance served by a load-balancer
as defined in [RFC7690]. The load-balancer does not implement the
mitigations defined in [RFC7690].
4. Reference Topology
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----------- ----------- ----------- -----------
| Upper | | | | | | Upper |
| Layer | | | | | | Layer |
| | | | | | | |
| IP |<-------->| IP |<-------->| IP |<-------->| IP |
| Layer | MTU | Layer | MTU | Layer | MTU | Layer |
----------- 9000 ----------- 4000 ----------- 1500 -----------
Source Router 1 Router 2 Destination
Node Node
Figure 1: Reference Topology
Figure 1 depicts a network that contains a Source Node, intermediate
nodes (i.e., Router 1, Router 2), and a Destination Node. The link
that connects the Source Node to Router 1 has an MTU of 9000 bytes.
The link that connects Router 1 to Router 2 has an MTU of 4000 bytes,
and the link that connects Router 2 to the Destination Node has an
MTU of 1500 bytes. The PMTU between the Source Node and the
Destination Node is 1500 bytes.
This topology will be used in examples throughout the document.
5. New IPv6 Destination Options
This document defines the IPv6 Truncation Eligible option and the
IPv6 Truncated Packet option.
5.1. The IPv6 Truncation Eligible Option
The IPv6 Truncation Eligible Option indicates that the packet is
eligible for truncation but has not been truncated. It contains the
following fields:
o Option Type - Truncation Eligible option. Value TBD by IANA. See
Notes below.
o Opt Data Len - Length of Option Data, measured in bytes. MUST be
equal to 0.
The IPv6 Destination Options header:
o MAY include a single instance of the Truncation Eligible option.
o SHOULD NOT include multiple instances of the Truncation Eligible
option.
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o SHOULD NOT include both the Truncation Eligible option and the
Truncated Packet option.
The IPv6 Hop-by-hop Options header SHOULD NOT include the Truncation
Eligible option.
Source nodes MUST NOT emit packets that contain both the Fragment
Header and Truncation Eligible option.
NOTE 1: According to [RFC8200], the highest-order two bits of the
Option Type (i.e., the "act" bits) specify the action taken by a
destination node that does not recognize Option Type. The required
action is skip over this option and continue processing the header.
Therefore, IANA is requested to assign this Option Type with "act"
bits "00".
NOTE 2: According to [RFC8200], the third-highest-order bit (i.e.,
the "chg" bit) of the Option Type specifies whether or not the Option
Data of that option can change en route to the packet's final
destination. Because this option contains no Option Data, IANA can
assign this Option Type without regard to the "chg" bit.
5.2. The IPv6 Truncated Packet Option
The IPv6 Truncated Packet Option indicates that the packet has been
truncated and is eligible for further truncation. It contains the
following fields:
o Option Type - Truncated Packet option. Value TBD by IANA. See
Notes below.
o Opt Data Len - Length of Option Data, measured in bytes. MUST be
equal to 0.
The IPv6 Destination Options:
o MAY include a single instance of the Truncated Packet option.
o SHOULD NOT include multiple instances of the Truncated Packet
option.
o SHOULD NOT include both the Truncated Packet option and the
Truncation Eligible option.
The IPv6 Hop-by-hop Options header SHOULD NOT include the Truncated
Packet option.
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Source nodes MUST NOT emit packets that contain both the Fragment
Header and Truncated Packet option.
NOTE 1: According to [RFC8200], the highest-order two bits of the
Option Type (i.e., the "act" bits) specify the action taken by a
destination node that does not recognize Option Type. The required
action is to discard the packet and, regardless of whether or not the
packet's Destination Address was a multicast address, send an ICMP
Parameter Problem, Code 2, message to the packet's Source Address,
pointing to the unrecognized Option Type. Therefore, IANA is
requested to assign this Option Type with "act" bits "10".
NOTE 2: According to [RFC8200], the third-highest-order bit (i.e.,
the "chg" bit) of the Option Type specifies whether or not the Option
Data of that option can change en route to the packet's final
destination. Because this option contains no Option Data, IANA can
assign this Option Type without regard to the "chg" bit.
6. PMTU Signaling Procedures
In the Reference Topology (Figure 1), an upper-layer protocol that
resides on the Source Node causes the IP layer to emit a packet. The
packet contains a Destination Options header and the Destination
Options header contains a Truncation Eligible option. The total
packet length, including all headers and the payload, is 1000 bytes.
Because the total packet length is less than the PMTU, the packet can
be delivered to the Destination Node without encountering any MTU
issues.
The IP layer on the Source Node forwards the packet to the Router 1,
Router 1 forwards the packet to Router 2, and the Router 2 forwards
the packet to the Destination Node. The IP layer on the Destination
Node examines the Destination Options header and finds the Truncation
Eligible option. The Truncation Eligible option requires no action
by the Destination Node. Therefore, the Destination Node processes
the next header and delivers the packet to an upper-layer protocol.
Subsequently, the upper-layer protocol that resides on the Source
Node causes the IP layer to emit another packet. This packet is
identical to the first, except that the total packet length is 2000
bytes. Because the packet length is greater than the PMTU, this
packet cannot be delivered without encountering an MTU issue.
The IP layer on the source node forwards the packet to Router 1.
Router 1 forwards the packet to Router 2, but the Router 2 cannot
forward the packet because its length exceeds the MTU of the next
link in the path. Because an MTU issue has been encountered, Router
2 examines the Destination Options header, searching for either a
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Truncation Eligible option or a Truncated Packet option. (Normally,
the Router 2 would ignore the Destination Options header).
Because Router 2 finds one of the above-mentioned options, it:
o Truncates the packet, so that its total length equals the MTU of
the next link in the path.
o Updates the Payload Length field in the IPv6 header.
o Overwrites all instances of the Truncation Eligible option with a
Truncated Packet option.
o Forwards the packet to the Destination Node.
The IP layer on the Destination Node receives the packet and examines
the Destination Options header. Because it finds the Truncated
Packet option, it sends an ICMP PTB message to the Source Node. The
MTU field in the ICMP PTB message is set to the packet's length.
By default, the IP layer on the Destination Node discards the
truncated packet, without delivering it to any upper-layer protocol.
However, the upper-layer protocol can register for the delivery of
truncated packets.
When the Source Node receives the ICMP PTB message, it updates its
PMTU estimate, as per [RFC8201].
7. Truncation Considerations
A packet can be truncated multiple times. In the Reference Topology
(Figure 1), assume that the Source Node sends a 5000 byte packet to
the Destination Node. Using the procedures described in Section 6,
Router 1 truncates this packet to 4000 bytes and Router 2 truncates
it again, to 1500 bytes.
A truncated packet MUST contain the basic IPv6 header, all extension
headers and the first upper-layer header. When an intermediate node
cannot forward a packet due to MTU issues, and the total length of
the basic IPv6 header, all extension headers, and first upper-layer
header exceeds the MTU of the next link in the path, the intermediate
node MUST discard the packet and send and ICMP PTB message to the
source node. It MUST NOT truncate the packet.
A truncated packet MUST NOT include the Fragment header. When an
intermediate node cannot forward a packet due to MTU issues, and the
packet contains a Fragment header, the intermediate node MUST discard
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the packet and send and ICMP PTB message to the source node. It MUST
NOT truncate the packet.
A truncated packet must have a total length that is greater than or
equal to the IPv6 minimum link MTU.
8. Destination Node Considerations
The following packet types are invalid::
o Packets that contain the Packet Truncated option and the Fragment
Header.
o Packets that contain the Packet Truncated option and have a total
length less than the IPv6 minimum link MTU.
When the destination node receives an invalid packet, it MUST:
o Discard the packet, without delivering it to any upper-layer
protocol, regardless of whether the upper-layer protocol has
registered for delivery of truncated packets.
o Send an ICMP Parameter Problem, Code 2, message to the packet's
Source Address, pointing to the Truncated Packet option.
9. Backward Compatibility
The procedures described in Section 6 assume that all nodes recognize
the Truncation Eligible option and Truncated Packet option. This
section explores backwards compatibility scenarios, where one or more
nodes do not recognize the above-mentioned options.
Assume that an intermediate node does not recognize the Truncation
Eligible option or the Truncated Packet option. When that node
receives a packet that it cannot forward because of an MTU issue, its
behavior is as described in [RFC8200]. The intermediate node
discards the packet and sends and ICMP PTB message to the source
node. It does not examine the Destination Options header, searching
for the above-mentioned options and it does not truncate the packet.
Now assume that a destination node does not recognize the Truncation
Eligible option. When that node receives a packet that contains the
Truncation Eligible option, its behavior is determined by the
highest-order two bits of the Option Type (i.e., the "act" bits).
Because the "act" bits are equal to "00", the destination node skips
over the option and continues to process the packet. This is exactly
what the destination node would have done if it had recognized the
Truncation Eligible option.
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Finally, assume that a destination node does not recognize the
Truncated Packet option. When that node receives a packet that
contains the Truncated Packet option, its behavior is determined by
the highest-order two bits of the Option Type (i.e., the "act" bits).
Because the "act" bits are equal to "10", the destination node
discards the packet and, regardless of whether or not the packet's
Destination Address was a multicast address, send an ICMP Parameter
Problem, Code 2, message to the packet's Source Address, pointing to
the Truncated Packet option. The destination node does not emit an
ICMP PTB message and it does not deliver the packet to an upper-layer
protocol.
The source node takes appropriate action when it receives the ICMP
Parameter Problem message.
10. Optimizations
The procedures described in Section 6 of this document can be
optimized by omitting the Truncation Eligible option on packets whose
length is known to be less than the PMTU (e.g., packets whose length
is less than the IPv6 minimum link MTU).
11. Upper-Layer Considerations
The procedures described herein rely upon the networks ability:
o To convey packets that contain destination options from the source
node to the destination node.
o To convey ICMP Parameter Problem messages in the reverse
direction.
Operational experience [RFC7872] reveals that a significant number of
networks drop packets that contain IPv6 destination options.
Likewise, many networks drop ICMP Parameter Problem messages.
[I-D.bonica-6man-unrecognized-opt] describes procedures that upper-
layer protocols can execute to verify that the above-mentioned
requirements are satisfied. Upper-layer protocols can execute these
procedures before emitting packets that contain the Truncation
Eligible option.
12. Encapsulating Security Payload Considerations
An IPv6 packet can contain both:
o An Encapsulating Security Payload (ESP) [RFC4303] header.
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o The Truncation Eligible Option.
In this case, the packet MUST contain a Destination Options header
that precedes the ESP. That Destination Options header contains the
Truncation Eligible Option and is not protected by the ESP. The
packet MAY also contain another Destination Options header the
follows the ESP. That Destination Options header is protected by the
ESP and MUST NOT contain the Truncation Eligible Option.
As per RFC 4303, a packet can contain two Destination Options headers
one preceding the ESP and one following the ESP.
13. Extension Header Considerations
According to [RFC8200], the following IPv6 extension headers can
contain options:
o The Hop-by-hop Options header.
o The Destination Options header.
The Hop-by-hop option can be examined by each node along the path to
a packet's destination. Destination options are examined by the
destination node only. However, [RFC2473] provides a precedent for
intermediate nodes examining the Destination options on an exception
basis. (See the Tunnel Encapsulation Limit.)
The Truncation Eligible option and the Truncated Packet option are
examined by:
o Intermediate nodes, on an exception basis (i.e, when the packet
cannot be forwarded due to MTU issues).
o The Destination node.
Therefore, the above-mentioned options can be processed most
efficiently when they are contained by the Destination Option header.
When contained by the Destination Options header, the above-mentioned
options are examined by intermediate nodes on an exception basis,
only when they are relevant. If contained by the Hop-by-hop Options
header, they are always examined by intermediate nodes, even when
they are irrelevant.
14. Security Considerations
PMTUD is vulnerable to ICMP PTB forgery attacks. The procedures
described herein do nothing to mitigate that vulnerability.
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The procedures described herein are susceptible to a new variation on
that attack, in which an attacker forges a truncated packet. In this
case, the attackers cause the Destination Node to produce an ICMP PTB
message on their behalf. To some degree, this vulnerability is
mitigated, because the Destination Node will not emit an ICMP PTB
message in response to a truncated packet whose length is less than
the IPv6 minimum link MTU.
15. IANA Considerations
IANA is requested to allocate the following codepoints from the
Destination Options and Hop-by-hop Options registry
(https://www.iana.org/assignments/ipv6-parameters/
ipv6-parameters.xhtml#ipv6-parameters-2).
o Truncation Eligible ("act-bits" are "00. "chg-bit" can be either 0
or 1.)
o Truncated Packet ("act-bits" are "10". "chg-but can be either 0 or
1.)
16. Acknowledgements
Special thanks to Mike Heard, Geoff Huston, Joel Jaeggli, Tom Jones,
Andy Smith, and Jinmei Tatuya who reviewed and commented on this
document.
17. References
17.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC4303] Kent, S., "IP Encapsulating Security Payload (ESP)",
RFC 4303, DOI 10.17487/RFC4303, December 2005,
<https://www.rfc-editor.org/info/rfc4303>.
[RFC4443] Conta, A., Deering, S., and M. Gupta, Ed., "Internet
Control Message Protocol (ICMPv6) for the Internet
Protocol Version 6 (IPv6) Specification", STD 89,
RFC 4443, DOI 10.17487/RFC4443, March 2006,
<https://www.rfc-editor.org/info/rfc4443>.
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[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.
[RFC8201] McCann, J., Deering, S., Mogul, J., and R. Hinden, Ed.,
"Path MTU Discovery for IP version 6", STD 87, RFC 8201,
DOI 10.17487/RFC8201, July 2017,
<https://www.rfc-editor.org/info/rfc8201>.
17.2. Informative References
[I-D.bonica-6man-unrecognized-opt]
Bonica, R. and J. Leddy, "The IPv6 Unrecognized Option",
draft-bonica-6man-unrecognized-opt-01 (work in progress),
June 2018.
[RFC2473] Conta, A. and S. Deering, "Generic Packet Tunneling in
IPv6 Specification", RFC 2473, DOI 10.17487/RFC2473,
December 1998, <https://www.rfc-editor.org/info/rfc2473>.
[RFC7690] Byerly, M., Hite, M., and J. Jaeggli, "Close Encounters of
the ICMP Type 2 Kind (Near Misses with ICMPv6 Packet Too
Big (PTB))", RFC 7690, DOI 10.17487/RFC7690, January 2016,
<https://www.rfc-editor.org/info/rfc7690>.
[RFC7872] Gont, F., Linkova, J., Chown, T., and W. Liu,
"Observations on the Dropping of Packets with IPv6
Extension Headers in the Real World", RFC 7872,
DOI 10.17487/RFC7872, June 2016,
<https://www.rfc-editor.org/info/rfc7872>.
Authors' Addresses
John Leddy
Comcast
1717 John F Kennedy Blvd.
Philadelphia, PA 19103
USA
Email: john_leddy@comcast.com
Leddy & Bonica Expires December 31, 2018 [Page 14]
Internet-Draft IPv6 Packet Truncation June 2018
Ron Bonica
Juniper Networks
2251 Corporate Park Drive
Herndon, Virginia 20171
USA
Email: rbonica@juniper.net
Leddy & Bonica Expires December 31, 2018 [Page 15]