RFC relevance of destination

As per Relevance of the word destination, we have this rfc below:

Network Working Group A.
Request for Comments: 2463
Obsoletes: 1885 S.
Category: Standards Track Cisco
December 1998

Internet Control Message Protocol (ICMPv6)
for the Internet Protocol Version 6 (IPv6)

Status of this

This document specifies an Internet standards track protocol for
Internet community, and requests discussion and suggestions
improvements. Please refer to the current edition of the "
Official Protocol Standards" (STD 1) for the standardization
and status of this protocol. Distribution of this memo is unlimited

Copyright

Copyright (C) The Internet Society (1998). All Rights Reserved

This document specifies a set of Internet Control Message
(ICMP) messages for use with version 6 of the Internet
(IPv6).

Table of

1. Introduction........................................2
2. ICMPv6 (ICMP for IPv6)..............................2
2.1 Message General Format.......................2
2.2 Message Source Address Determination.........3
2.3 Message Checksum Calculation.................4
2.4 Message Processing Rules.....................4
3. ICMPv6 Error Messages...............................6
3.1 Destination Unreachable Message..............6
3.2 Packet Too Big Message...................... 8
3.3 Time Exceeded Message....................... 9
3.4 Parameter Problem Message...................10
4. ICMPv6 Informational Messages......................11
4.1 Echo Request Message........................11
4.2 Echo Reply Message..........................12
5. Security Considerations............................13
6. References.........................................14
7. Acknowledgments....................................15

Conta & Deering Standards Track [Page 1]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

8. Authors' Addresses.................................16
Appendix A - Changes since RFC 1885...................17
Full Copyright Statement..............................18

1.

The Internet Protocol, version 6 (IPv6) is a new version of IP. IPv
uses the Internet Control Message Protocol (ICMP) as defined for IPv
[RFC-792], with a number of changes. The resulting protocol
called ICMPv6, and has an IPv6 Next Header value of 58.

This document describes the format of a set of control messages
in ICMPv6. It does not describe the procedures for using
messages to achieve functions like Path MTU discovery;
procedures are described in other documents (e.g., [PMTU]).
documents may also introduce additional ICMPv6 message types, such
Neighbor Discovery messages [IPv6-DISC], subject to the general
for ICMPv6 messages given in section 2 of this document

Terminology defined in the IPv6 specification [IPv6] and the IPv
Routing and Addressing specification [IPv6-ADDR] applies to
document as well

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in
document are to be interpreted as described in [RFC-2119].

2. ICMPv6 (ICMP for IPv6)

ICMPv6 is used by IPv6 nodes to report errors encountered
processing packets, and to perform other internet-layer functions
such as diagnostics (ICMPv6 "ping"). ICMPv6 is an integral part
IPv6 and MUST be fully implemented by every IPv6 node

2.1 Message General

ICMPv6 messages are grouped into two classes: error messages
informational messages. Error messages are identified as such
having a zero in the high-order bit of their message Type
values. Thus, error messages have message Types from 0 to 127;
informational messages have message Types from 128 to 255.

This document defines the message formats for the following ICMPv
messages

Conta & Deering Standards Track [Page 2]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

ICMPv6 error messages

1 Destination Unreachable (see section 3.1)
2 Packet Too Big (see section 3.2)
3 Time Exceeded (see section 3.3)
4 Parameter Problem (see section 3.4)

ICMPv6 informational messages

128 Echo Request (see section 4.1)
129 Echo Reply (see section 4.2)

Every ICMPv6 message is preceded by an IPv6 header and zero or
IPv6 extension headers. The ICMPv6 header is identified by a
Header value of 58 in the immediately preceding header. (NOTE:
is different than the value used to identify ICMP for IPv4.)

The ICMPv6 messages have the following general format

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ Message Body +
| |

The type field indicates the type of the message. Its
determines the format of the remaining data

The code field depends on the message type. It is used to create
additional level of message granularity

The checksum field is used to detect data corruption in the ICMPv
message and parts of the IPv6 header

2.2 Message Source Address

A node that sends an ICMPv6 message has to determine both the
and Destination IPv6 Addresses in the IPv6 header before
the checksum. If the node has more than one unicast address, it
choose the Source Address of the message as follows

(a) If the message is a response to a message sent to one of
node's unicast addresses, the Source Address of the reply
be that same address

Conta & Deering Standards Track [Page 3]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

(b) If the message is a response to a message sent to a multicast
anycast group in which the node is a member, the Source
of the reply must be a unicast address belonging to
interface on which the multicast or anycast packet was received

(c) If the message is a response to a message sent to an
that does not belong to the node, the Source Address should
that unicast address belonging to the node that will be
helpful in diagnosing the error. For example, if the message
a response to a packet forwarding action that cannot
successfully, the Source Address should be a unicast
belonging to the interface on which the packet
failed

(d) Otherwise, the node's routing table must be examined
determine which interface will be used to transmit the
to its destination, and a unicast address belonging to
interface must be used as the Source Address of the message

2.3 Message Checksum

The checksum is the 16-bit one's complement of the one's
sum of the entire ICMPv6 message starting with the ICMPv6
type field, prepended with a "pseudo-header" of IPv6 header fields
as specified in [IPv6, section 8.1]. The Next Header value used
the pseudo-header is 58. (NOTE: the inclusion of a pseudo-header
the ICMPv6 checksum is a change from IPv4; see [IPv6] for
rationale for this change.)

For computing the checksum, the checksum field is set to zero

2.4 Message Processing

Implementations MUST observe the following rules when
ICMPv6 messages (from [RFC-1122]):

(a) If an ICMPv6 error message of unknown type is received, it
be passed to the upper layer

(b) If an ICMPv6 informational message of unknown type is received
it MUST be silently discarded

(c) Every ICMPv6 error message (type < 128) includes as much of
IPv6 offending (invoking) packet (the packet that caused
error) as will fit without making the error message
exceed the minimum IPv6 MTU [IPv6].

Conta & Deering Standards Track [Page 4]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

(d) In those cases where the internet-layer protocol is required
pass an ICMPv6 error message to the upper-layer process,
upper-layer protocol type is extracted from the original
(contained in the body of the ICMPv6 error message) and used
select the appropriate upper-layer process to handle the error

If the original packet had an unusually large amount
extension headers, it is possible that the upper-layer
type may not be present in the ICMPv6 message, due to
of the original packet to meet the minimum IPv6 MTU [IPv6]
limit. In that case, the error message is silently
after any IPv6-layer processing

(e) An ICMPv6 error message MUST NOT be sent as a result
receiving

(e.1) an ICMPv6 error message,

(e.2) a packet destined to an IPv6 multicast address (there
two exceptions to this rule: (1) the Packet Too
Message - Section 3.2 - to allow Path MTU discovery
work for IPv6 multicast, and (2) the Parameter
Message, Code 2 - Section 3.4 - reporting an
IPv6 option that has the Option Type highest-order
bits set to 10),

(e.3) a packet sent as a link-layer multicast, (the
from e.2 applies to this case too),

(e.4) a packet sent as a link-layer broadcast, (the
from e.2 applies to this case too),

(e.5) a packet whose source address does not uniquely
a single node -- e.g., the IPv6 Unspecified Address,
IPv6 multicast address, or an address known by the
message sender to be an IPv6 anycast address

(f) Finally, in order to limit the bandwidth and forwarding
incurred sending ICMPv6 error messages, an IPv6 node MUST
the rate of ICMPv6 error messages it sends. This situation
occur when a source sending a stream of erroneous packets
to heed the resulting ICMPv6 error messages. There are
variety of ways of implementing the rate-limiting function,
example

(f.1) Timer-based - for example, limiting the rate
transmission of error messages to a given source, or
any source, to at most once every T milliseconds

Conta & Deering Standards Track [Page 5]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

(f.2) Bandwidth-based - for example, limiting the rate at
error messages are sent from a particular interface
some fraction F of the attached link's bandwidth

The limit parameters (e.g., T or F in the above examples)
be configurable for the node, with a conservative default
(e.g., T = 1 second, NOT 0 seconds, or F = 2 percent, NOT 100
percent).

The following sections describe the message formats for the
ICMPv6 messages

3. ICMPv6 Error

3.1 Destination Unreachable

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Unused |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| As much of invoking packet |
+ as will fit without the ICMPv6 packet +
| exceeding the minimum IPv6 MTU [IPv6] |

IPv6 Fields

Destination

Copied from the Source Address field of the
packet

ICMPv6 Fields

Type 1

Code 0 - no route to
1 - communication with
administratively
2 - (not assigned
3 - address
4 - port

Unused This field is unused for all code values
It must be initialized to zero by the
and ignored by the receiver

Conta & Deering Standards Track [Page 6]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

A Destination Unreachable message SHOULD be generated by a router,
by the IPv6 layer in the originating node, in response to a
that cannot be delivered to its destination address for reasons
than congestion. (An ICMPv6 message MUST NOT be generated if
packet is dropped due to congestion.)

If the reason for the failure to deliver is lack of a matching
in the forwarding node's routing table, the Code field is set to 0
(NOTE: this error can occur only in nodes that do not hold a "
route" in their routing tables).

If the reason for the failure to deliver is
prohibition, e.g., a "firewall filter", the Code field is set to 1.

If there is any other reason for the failure to deliver, e.g.,
inability to resolve the IPv6 destination address into
corresponding link address, or a link-specific problem of some sort
then the Code field is set to 3.

A destination node SHOULD send a Destination Unreachable message
Code 4 in response to a packet for which the transport
(e.g., UDP) has no listener, if that transport protocol has
alternative means to inform the sender

Upper layer

A node receiving the ICMPv6 Destination Unreachable message
notify the upper-layer process

Conta & Deering Standards Track [Page 7]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

3.2 Packet Too Big

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MTU |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| As much of invoking packet |
+ as will fit without the ICMPv6 packet +
| exceeding the minimum IPv6 MTU [IPv6] |

IPv6 Fields

Destination

Copied from the Source Address field of the
packet

ICMPv6 Fields

Type 2

Code Set to 0 (zero) by the sender and ignored by

MTU The Maximum Transmission Unit of the next-hop link

A Packet Too Big MUST be sent by a router in response to a
that it cannot forward because the packet is larger than the MTU
the outgoing link. The information in this message is used as
of the Path MTU Discovery process [PMTU].

Sending a Packet Too Big Message makes an exception to one of
rules of when to send an ICMPv6 error message, in that unlike
messages, it is sent in response to a packet received with an IPv
multicast destination address, or a link-layer multicast or link
layer broadcast address

Upper layer

An incoming Packet Too Big message MUST be passed to the upper-
process

Conta & Deering Standards Track [Page 8]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

3.3 Time Exceeded

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Unused |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| As much of invoking packet |
+ as will fit without the ICMPv6 packet +
| exceeding the minimum IPv6 MTU [IPv6] |

IPv6 Fields

Destination
Copied from the Source Address field of the
packet

ICMPv6 Fields

Type 3

Code 0 - hop limit exceeded in

1 - fragment reassembly time

Unused This field is unused for all code values
It must be initialized to zero by the
and ignored by the receiver

If a router receives a packet with a Hop Limit of zero, or a
decrements a packet's Hop Limit to zero, it MUST discard the
and send an ICMPv6 Time Exceeded message with Code 0 to the source
the packet. This indicates either a routing loop or too small
initial Hop Limit value

The rules for selecting the Source Address of this message
defined in section 2.2.

Upper layer

An incoming Time Exceeded message MUST be passed to the upper-
process

Conta & Deering Standards Track [Page 9]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

3.4 Parameter Problem

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Pointer |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| As much of invoking packet |
+ as will fit without the ICMPv6 packet +
| exceeding the minimum IPv6 MTU [IPv6] |

IPv6 Fields

Destination

Copied from the Source Address field of the
packet

ICMPv6 Fields

Type 4

Code 0 - erroneous header field

1 - unrecognized Next Header type

2 - unrecognized IPv6 option

Pointer Identifies the octet offset within
invoking packet where the error was detected

The pointer will point beyond the end of the ICMPv
packet if the field in error is beyond what can
in the maximum size of an ICMPv6 error message

If an IPv6 node processing a packet finds a problem with a field
the IPv6 header or extension headers such that it cannot
processing the packet, it MUST discard the packet and SHOULD send
ICMPv6 Parameter Problem message to the packet's source,
the type and location of the problem

The pointer identifies the octet of the original packet's
where the error was detected. For example, an ICMPv6 message
Type field = 4, Code field = 1, and Pointer field = 40 would

Conta & Deering Standards Track [Page 10]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

that the IPv6 extension header following the IPv6 header of
original packet holds an unrecognized Next Header field value

Upper layer

A node receiving this ICMPv6 message MUST notify the upper-
process

4. ICMPv6 Informational

4.1 Echo Request

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Identifier | Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Data ...
+-+-+-+-+-

IPv6 Fields

Destination

Any legal IPv6 address

ICMPv6 Fields

Type 128

Code 0

Identifier An identifier to aid in matching Echo
to this Echo Request. May be zero

Sequence

A sequence number to aid in matching Echo
to this Echo Request. May be zero

Data Zero or more octets of arbitrary data

Conta & Deering Standards Track [Page 11]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

Every node MUST implement an ICMPv6 Echo responder function
receives Echo Requests and sends corresponding Echo Replies. A
SHOULD also implement an application-layer interface for sending
Requests and receiving Echo Replies, for diagnostic purposes

Upper layer

Echo Request messages MAY be passed to processes receiving
messages

4.2 Echo Reply

0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Identifier | Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Data ...
+-+-+-+-+-

IPv6 Fields

Destination

Copied from the Source Address field of the
Echo Request packet

ICMPv6 Fields

Type 129

Code 0

Identifier The identifier from the invoking Echo Request message

Sequence The sequence number from the invoking Echo
Number message

Data The data from the invoking Echo Request message

Conta & Deering Standards Track [Page 12]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

Every node MUST implement an ICMPv6 Echo responder function
receives Echo Requests and sends corresponding Echo Replies. A
SHOULD also implement an application-layer interface for sending
Requests and receiving Echo Replies, for diagnostic purposes

The source address of an Echo Reply sent in response to a
Echo Request message MUST be the same as the destination address
that Echo Request message

An Echo Reply SHOULD be sent in response to an Echo Request
sent to an IPv6 multicast address. The source address of the
MUST be a unicast address belonging to the interface on which
multicast Echo Request message was received

The data received in the ICMPv6 Echo Request message MUST be
entirely and unmodified in the ICMPv6 Echo Reply message

Upper layer

Echo Reply messages MUST be passed to the process that originated
Echo Request message. It may be passed to processes that did
originate the Echo Request message

5. Security

5.1 Authentication and Encryption of ICMP

ICMP protocol packet exchanges can be authenticated using the
Authentication Header [IPv6-AUTH]. A node SHOULD include
Authentication Header when sending ICMP messages if a
association for use with the IP Authentication Header exists for
destination address. The security associations may have been
through manual configuration or through the operation of some
management protocol

Received Authentication Headers in ICMP packets MUST be verified
correctness and packets with incorrect authentication MUST be
and discarded

It SHOULD be possible for the system administrator to configure
node to ignore any ICMP messages that are not authenticated
either the Authentication Header or Encapsulating Security Payload
Such a switch SHOULD default to allowing unauthenticated messages

Conta & Deering Standards Track [Page 13]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

Confidentiality issues are addressed by the IP Security
and the IP Encapsulating Security Payload documents [IPv6-SA, IPv6-
ESP].

5.2 ICMP

ICMP messages may be subject to various attacks. A
discussion can be found in the IP Security Architecture [IPv6-SA].
brief discussion of such attacks and their prevention is as follows

1. ICMP messages may be subject to actions intended to cause
receiver believe the message came from a different source than
message originator. The protection against this attack can
achieved by applying the IPv6 Authentication mechanism [IPv6-Auth
to the ICMP message

2. ICMP messages may be subject to actions intended to cause
message or the reply to it go to a destination different than
message originator's intention. The ICMP checksum
provides a protection mechanism against changes by a
interceptor in the destination and source address of the IP
carrying that message, provided the ICMP checksum field
protected against change by authentication [IPv6-Auth]
encryption [IPv6-ESP] of the ICMP message

3. ICMP messages may be subject to changes in the message fields,
payload. The authentication [IPv6-Auth] or encryption [IPv6-ESP
of the ICMP message is a protection against such actions

4. ICMP messages may be used as attempts to perform denial of
attacks by sending back to back erroneous IP packets.
implementation that correctly followed section 2.4, paragraph (f
of this specifications, would be protected by the ICMP error
limiting mechanism

6.

[IPv6] Deering, S. and R. Hinden, "Internet Protocol,
6, (IPv6) Specification", RFC 2460, December 1998.

[IPv6-ADDR] Hinden, R. and S. Deering, "IP Version 6
Architecture", RFC 2373, July 1998.

[IPv6-DISC] Narten, T., Nordmark, E. and W. Simpson, "
Discovery for IP Version 6 (IPv6)", RFC 2461,
1998.

Conta & Deering Standards Track [Page 14]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

[RFC-792] Postel, J., "Internet Control Message Protocol", STD 5,
RFC 792, September 1981.

[RFC-1122] Braden, R., "Requirements for Internet Hosts -
Communication Layers", STD 5, RFC 1122, August 1989.

[PMTU] McCann, J., Deering, S. and J. Mogul, "Path
Discovery for IP version 6", RFC 1981, August 1996.

[RFC-2119] Bradner, S., "Key words for use in RFCs to
Requirement Levels", BCP 14, RFC 2119, March 1997.

[IPv6-SA] Kent, S. and R. Atkinson, "Security Architecture for
Internet Protocol", RFC 2401, November 1998.

[IPv6-Auth] Kent, S. and R. Atkinson, "IP Authentication Header",
RFC 2402, November 1998.

[IPv6-ESP] Kent, S. and R. Atkinson, "IP Encapsulating
Protocol (ESP)", RFC 2406, November 1998.

7.

The document is derived from previous ICMP drafts of the SIPP
IPng working group

The IPng working group and particularly Robert Elz, Jim Bound,
Simpson, Thomas Narten, Charlie Lynn, Bill Fink, Scott Bradner
Dimitri Haskin, and Bob Hinden (in chronological order)
extensive review information and feedback

Conta & Deering Standards Track [Page 15]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

8. Authors'

Alex
Lucent Technologies Inc
300 Baker Ave, Suite 100
Concord, MA 01742

Phone: +1 978 287-2842
EMail: aconta@lucent.

Stephen
Cisco Systems, Inc
170 West Tasman
San Jose, CA 95134-1706

Phone: +1 408 527-8213
EMail: deering@cisco.

Conta & Deering Standards Track [Page 16]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

Appendix A - Changes from RFC 1885

Version 2-02

- Excluded mentioning informational replies from paragraph (f.2)
section 2.4.
- In "Upper layer notification" sections changed "upper-
protocol" and "User Interface" to "process".
- Changed section 5.2, item 2 and 3 to also refer to
authentication
- Removed item 5. from section 5.2 on denial of service attacks
- Updated phone numbers and Email addresses in the "Authors
Addresses" section

Version 2-01

- Replaced all references to "576 octets" as the maximum for an
message size with "minimum IPv6 MTU" as defined by the base IPv
specification
- Removed rate control from informational messages
- Added requirement that receivers ignore Code value in Packet
Big message
- Removed "Not a Neighbor" (code 2) from destination
message
- Fixed typos and update references

Version 2-00

- Applied rate control to informational
- Removed section 2.4 on Group Management ICMP
- Removed references to IGMP in Abstract and Section 1.
- Updated references to other IPv6
- Removed references to RFC-1112 in Abstract, and Section 1, and
RFC-1191 in section 1, and section 3.2
- Added security
- Added Appendix A -

Conta & Deering Standards Track [Page 17]

RFC 2463 ICMPv6 (ICMP for IPv6) December 1998

Full Copyright

Copyright (C) The Internet Society (1998). All Rights Reserved

This document and translations of it may be copied and furnished
others, and derivative works that comment on or otherwise explain
or assist in its implementation may be prepared, copied,
and distributed, in whole or in part, without restriction of
kind, provided that the above copyright notice and this paragraph
included on all such copies and derivative works. However,
document itself may not be modified in any way, such as by
the copyright notice or references to the Internet Society or
Internet organizations, except as needed for the purpose
developing Internet standards in which case the procedures
copyrights defined in the Internet Standards process must
followed, or as required to translate it into languages other
English

The limited permissions granted above are perpetual and will not
revoked by the Internet Society or its successors or assigns

This document and the information contained herein is provided on
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED,
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE

Conta & Deering Standards Track [Page 18]

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