draft-ietf-ipngwg-icmp-02.txt   rfc1885.txt 
Network Working Group A. Conta (Digital Equipment Corporation) Network Working Group A. Conta, Digital Equipment Corporation
INTERNET-DRAFT S. Deering (Xerox PARC) Request for Comments: 1885 S. Deering, Xerox PARC
June 1995 Category: Standards Track December 1995
Internet Control Message Protocol (ICMPv6) Internet Control Message Protocol (ICMPv6)
for the Internet Protocol Version 6 (IPv6) for the Internet Protocol Version 6 (IPv6)
Specification Specification
<draft-ietf-ipngwg-icmp-02.txt>
Status of this Memo Status of this Memo
This document is an Internet Draft. Internet Drafts are working This document specifies an Internet standards track protocol for the
documents of the Internet Engineering Task Force (IETF), its Areas, Internet community, and requests discussion and suggestions for
and its Working Groups. Note that other groups may also distribute improvements. Please refer to the current edition of the "Internet
working documents as Internet Drafts. Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Internet Drafts are draft documents valid for a maximum of six Abstract
months. Internet Drafts may be updated, replaced, or obsoleted by
other documents at any time. It is not appropriate to use Internet
Drafts as reference material or to cite them other than as a "working
draft" or "work in progress."
To learn the current status of any Internet-Draft, please check the This document specifies a set of Internet Control Message Protocol
``1id-abstracts.txt'' listing contained in the Internet- Drafts (ICMP) messages for use with version 6 of the Internet Protocol
Shadow Directories on ds.internic.net (US East Coast), nic.nordu.net (IPv6). The Internet Group Management Protocol (IGMP) messages
(Europe), ftp.isi.edu (US West Coast), or munnari.oz.au (Pacific specified in STD 5, RFC 1112 have been merged into ICMP, for IPv6,
Rim). and are included in this document.
Distribution of this memo is unlimited. Table of Contents
Abstract 1. Introduction........................................3
This document specifies a set of Internet Control Message Protocol 2. ICMPv6 (ICMP for IPv6)..............................3
(ICMP) messages for use with version 6 of the Internet Protocol
(IPv6). The Internet Group Management Protocol (IGMP) messages
specified in RFC-1112 have been merged into ICMP, for IPv6, and are
included in this document.
Table of Contents 2.1 Message General Format.......................3
1. Introduction........................................3
2. ICMPv6 (ICMP for IPv6)..............................3 2.2 Message Source Address Determination.........4
2.1 Message General Format.......................3
2.2 Message Source Address Determination.........5 2.3 Message Checksum Calculation.................5
2.3 Message Checksum Calculation.................5
2.4 Message Processing Rules.....................8 2.4 Message Processing Rules.....................5
3. ICMPv6 Error Messages..............................10
3.1 Destination Unreachable Message.............10 3. ICMPv6 Error Messages...............................8
3.2 Packet Too Big Message......................12
3.3 Time Exceeded Message.......................13 3.1 Destination Unreachable Message..............8
3.4 Parameter Problem Message...................14
4. ICMPv6 Informational Messages......................16 3.2 Packet Too Big Message......................10
4.1 Echo Request Message........................16
4.2 Echo Reply Message..........................17 3.3 Time Exceeded Message.......................11
4.3 Group Membership Messages...................18
5. References.........................................19 3.4 Parameter Problem Message...................12
6. Acknowledgements...................................20
7. Security Considerations............................20 4. ICMPv6 Informational Messages......................14
Authors' Addresses....................................21
1. Introduction 4.1 Echo Request Message........................14
4.2 Echo Reply Message..........................15
4.3 Group Membership Messages...................17
5. References.........................................19
6. Acknowledgements...................................19
7. Security Considerations............................19
Authors' Addresses....................................20
1. Introduction
The Internet Protocol, version 6 (IPv6) is a new version of IP. IPv6 The Internet Protocol, version 6 (IPv6) is a new version of IP. IPv6
uses the Internet Control Message Protocol (ICMP) as defined for IPv4 uses the Internet Control Message Protocol (ICMP) as defined for IPv4
[RFC-792], with a number of changes. The Internet Group Membership [RFC-792], with a number of changes. The Internet Group Membership
Protocol (IGMP) specified for IPv4 [RFC-1112] has also been revised Protocol (IGMP) specified for IPv4 [RFC-1112] has also been revised
and has been absorbed into ICMP for IPv6. The resulting protocol is and has been absorbed into ICMP for IPv6. The resulting protocol is
called ICMPv6, and has an IPv6 Next Header value 58. called ICMPv6, and has an IPv6 Next Header value of 58.
This document describes the format of a set of control messages used This document describes the format of a set of control messages used
in ICMPv6. It does not describe the procedures for using these in ICMPv6. It does not describe the procedures for using these
messages to achieve functions like Path MTU discovery or multicast messages to achieve functions like Path MTU discovery or multicast
group membership maintenance; such procedures are described in other group membership maintenance; such procedures are described in other
documents (e.g., [RFC-1112, RFC-1191]). Other documents may also documents (e.g., [RFC-1112, RFC-1191]). Other documents may also
introduce additional ICMPv6 message types, such as Neighbor Discovery introduce additional ICMPv6 message types, such as Neighbor Discovery
messages [IPv6-DISC], subject to the general rules for ICMPv6 messages [IPv6-DISC], subject to the general rules for ICMPv6
messages given in section 2 of this document. messages given in section 2 of this document.
Terminology defined in the IPv6 specification [IPv6] and the IPv6 Terminology defined in the IPv6 specification [IPv6] and the IPv6
Routing and Addressing specification [IPv6-ADDR] applies to this Routing and Addressing specification [IPv6-ADDR] applies to this
document as well. document as well.
2. ICMPv6 (ICMP for IPv6) 2. ICMPv6 (ICMP for IPv6)
ICMPv6 is used by IPv6 nodes to report errors encountered in ICMPv6 is used by IPv6 nodes to report errors encountered in
processing packets, and to perform other internet-layer functions, processing packets, and to perform other internet-layer functions,
such as diagnostics (ICMPv6 "ping") and multicast membership such as diagnostics (ICMPv6 "ping") and multicast membership
reporting. ICMPv6 is an integral part of IPv6 and MUST be fully reporting. ICMPv6 is an integral part of IPv6 and MUST be fully
implemented by every IPv6 node. implemented by every IPv6 node.
2.1 Message General Format 2.1 Message General Format
ICMPv6 messages are grouped into two classes: error messages and ICMPv6 messages are grouped into two classes: error messages and
informational messages. Error messages are identified as such by informational messages. Error messages are identified as such by
having a zero in the high-order bit of their message Type field having a zero in the high-order bit of their message Type field
values. Thus, error messages have message Types from 0 to 127; values. Thus, error messages have message Types from 0 to 127;
informational messages have message Types from 128 to 255. informational messages have message Types from 128 to 255.
This document defines the message formats for the following ICMPv6 This document defines the message formats for the following ICMPv6
messages: messages:
ICMPv6 error messages: ICMPv6 error messages:
1 Destination Unreachable (see section 3.1) 1 Destination Unreachable (see section 3.1)
2 Packet Too Big (see section 3.2) 2 Packet Too Big (see section 3.2)
3 Time Exceeded (see section 3.3) 3 Time Exceeded (see section 3.3)
4 Parameter Problem (see section 3.4) 4 Parameter Problem (see section 3.4)
ICMPv6 informational messages: ICMPv6 informational messages:
128 Echo Request (see section 4.1) 128 Echo Request (see section 4.1)
129 Echo Reply (see section 4.2) 129 Echo Reply (see section 4.2)
130 Group Membership Query (see section 4.3) 130 Group Membership Query (see section 4.3)
131 Group Membership Report (see section 4.3) 131 Group Membership Report (see section 4.3)
132 Group Membership Termination (see section 4.3) 132 Group Membership Reduction (see section 4.3)
Every ICMPv6 message is preceded by an IPv6 header and zero or more Every ICMPv6 message is preceded by an IPv6 header and zero or more
IPv6 extension headers. The ICMPv6 header is identified by a Next IPv6 extension headers. The ICMPv6 header is identified by a Next
Header value of 58 in the immediately preceding header. (NOTE: this Header value of 58 in the immediately preceding header. (NOTE: this
is different than the value used to identify ICMP for IPv4.) is different than the value used to identify ICMP for IPv4.)
The ICMPv6 messages have the following general format: The ICMPv6 messages have the following general format:
0 1 2 3 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 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 | | Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | |
+ Message Body + + Message Body +
| | | |
The type field indicates the type of the message. Its value The type field indicates the type of the message. Its value
determines the format of the remaining data. determines the format of the remaining data.
The code field depends on the message type. It is used to create an The code field depends on the message type. It is used to create an
additional level of message granularity. additional level of message granularity.
The checksum is the 16-bit one's complement of the one's complement The checksum field is used to detect data corruption in the ICMPv6
sum of the IPv6 Source Address, the IPv6 Destination Address the IPv6 message and parts of the IPv6 header.
Payload Length, the Next Header type that identifies ICMPv6 (value =
58), and the entire ICMPv6 message starting with the ICMPv6 message
type.
2.2 Message Source Address Determination 2.2 Message Source Address Determination
A node that sends an ICMPv6 message has to determine both the Source A node that sends an ICMPv6 message has to determine both the Source
and Destination IPv6 Addresses in the IPv6 header before calculating and Destination IPv6 Addresses in the IPv6 header before calculating
the checksum. If the node has more than one unicast address, it must the checksum. If the node has more than one unicast address, it must
choose the Source Address of the message as follows: choose the Source Address of the message as follows:
(a) If the message is a response to a message sent to one of the (a) If the message is a response to a message sent to one of the
node's unicast addresses, the Source Address of the reply must be node's unicast addresses, the Source Address of the reply must
that same address. be that same address.
(b) If the message is a response to a message sent to a multicast or
anycast group in which the node is a member, the Source Address
of the reply must be a unicast address belonging to the interface
on which the multicast packet was received.
(c) If the message is a response to a message sent to an address that
does not belong to the node, the Source Address should be that
unicast address belonging to the node that will be most helpful
in diagnosing the error. For example, if the message is a
response to a packet forwarding action that cannot complete
successfully, the Source Address should be a unicast address
belonging to the interface on which the packet forwarding failed.
(d) Otherwise, the node's routing table must be examined to determine
which interface will be used to transmit the message to its
destination, and a unicast address belonging to that interface
must be used as the Source Address of the message.
2.3 Message Checksum Calculation
An illustration of the IPv6 and ICMPv6 header fields fetched into a
pseudo-header for calculating the ICMPv6 checksum is:
From the IPv6 Header:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Source Address +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Destination Address +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| zero | Next Hdr = 58 | Payload Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
From the ICMPv6 Header and Message:
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 = zero |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ Message Body +
| |
An illustration of the IPv6, IPv6 Hop-by-Hop Jumbo Payload Option and
ICMPv6 headers fields fetched into a pseudo-header for calculating
the ICMPv6 checksum in case of a Jumbo Payload (IPv6 packet payload
longer than 65535 octets) is:
From the IPv6 Header:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Source Address +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Destination Address +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| zero | Next Hdr = 58 | zero |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
From the IPv6 Hop-by-Hop Jumbo Payload Option Extension Header:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Payload Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
From the ICMPv6 Header and Message: (b) If the message is a response to a message sent to a multicast or
anycast group in which the node is a member, the Source Address
of the reply must be a unicast address belonging to the
interface on which the multicast or anycast packet was received.
0 1 2 3 (c) If the message is a response to a message sent to an address
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 that does not belong to the node, the Source Address should be
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ that unicast address belonging to the node that will be most
| Type | Code | Checksum = zero | helpful in diagnosing the error. For example, if the message is
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ a response to a packet forwarding action that cannot complete
| | successfully, the Source Address should be a unicast address
+ Message Body + belonging to the interface on which the packet forwarding
| | failed.
The ICMPv6 checksum calculation rules are: (d) Otherwise, the node's routing table must be examined to
determine which interface will be used to transmit the message
to its destination, and a unicast address belonging to that
interface must be used as the Source Address of the message.
(a) If the packet contains a Routing header, the Destination Address 2.3 Message Checksum Calculation
used in the pseudo-header is that of the final destination. At
the originating system, that address will be in the last element
of the Routing header; at the recipient(s), that address will be
in the Destination Address field of the IPv6 header.
(b) The Next Header value in the pseudo-header identifies the ICMPv6 The checksum is the 16-bit one's complement of the one's complement
protocol (e.g., 58). It will differ from the Next Header value in sum of the entire ICMPv6 message starting with the ICMPv6 message
the IPv6 header if there are additional headers between the IPv6 type field, prepended with a "pseudo-header" of IPv6 header fields,
header and the ICMPv6 header. as specified in [IPv6, section 8.1]. The Next Header value used in
the pseudo-header is 58. (NOTE: the inclusion of a pseudo-header in
the ICMPv6 checksum is a change from IPv4; see [IPv6] for the
rationale for this change.)
(c) The Payload Length used in the pseudo-header is the length of the For computing the checksum, the checksum field is set to zero.
ICMPv6 message, including the ICMPv6 header. It will be less
than the Payload Length in the IPv6 header or in the IPv6 Hop-
by-Hop Jumbo Payload Option header if there are additional
headers between the IPv6 header and the ICMPv6 header,
respectively the IPv6 Hop-by-Hop Jumbo Option Header and the
ICMPv6 Header.
(d) For computing the checksum, the checksum field is set to zero. 2.4 Message Processing Rules
(NOTE: the inclusion of the IPv6 header fields in the ICMPv6 Implementations MUST observe the following rules when processing
checksum is a change from IPv4; see [IPv6] for the rationale for ICMPv6 messages (from [RFC-1122]):
this change.)
2.4 Message Processing Rules (a) If an ICMPv6 error message of unknown type is received, it MUST
be passed to the upper layer.
Implementations MUST observe the following rules when processing (b) If an ICMPv6 informational message of unknown type is received,
ICMPv6 messages (from [RFC-1122]): it MUST be silently discarded.
(a) If an ICMPv6 error message of unknown type is received, it MUST (c) Every ICMPv6 error message (type < 128) includes as much of the
be passed to the upper layer. IPv6 offending (invoking) packet (the packet that caused the
error) as will fit without making the error message packet
exceed 576 octets.
(b) If an ICMPv6 informational message of unknown type is received, (d) In those cases where the internet-layer protocol is required to
it MUST be silently discarded. pass an ICMPv6 error message to the upper-layer protocol, the
upper-layer protocol type is extracted from the original packet
(contained in the body of the ICMPv6 error message) and used to
select the appropriate upper-layer protocol entity to handle the
error.
(c) Every ICMPv6 error message (type < 128) includes as much of the If the original packet had an unusually large amount of
IPv6 offending (invoking) packet (the packet that causes the extension headers, it is possible that the upper-layer protocol
error) as will fit without making the error message packet exceed type may not be present in the ICMPv6 message, due to truncation
576 octets. of the original packet to meet the 576-octet limit. In that
case, the error message is silently dropped after any IPv6-layer
processing.
(d) In those cases where the Internet layer is required to pass a (e) An ICMPv6 error message MUST NOT be sent as a result of
ICMPv6 error message to the transport layer, the IPv6 Transport receiving:
Protocol is extracted from the original header (contained in the
body of the ICMPv6 error message) and used to select the
appropriate transport protocol entity to handle the error.
(e) An ICMPv6 error message MUST NOT be sent as a result of (e.1) an ICMPv6 error message, or
receiving:
(e.1) an ICMPv6 error message, or (e.2) a packet destined to an IPv6 multicast address (there are
two exceptions to this rule: (1) the Packet Too Big
Message - Section 3.2 - to allow Path MTU discovery to
work for IPv6 multicast, and (2) the Parameter Problem
Message, Code 2 - Section 3.4 - reporting an unrecognized
IPv6 option that has the Option Type highest-order two
bits set to 10), or
(e.2) a packet destined to an IPv6 multicast address (an (e.3) a packet sent as a link-layer multicast, (the exception
exception to this rule is the Packet Too Big Message - from e.2 applies to this case too), or
Section 3.2 - to allow Path MTU discovery to work for IPv6
multicast), or
(e.3) a packet sent as a link-layer multicast, (the exception (e.4) a packet sent as a link-layer broadcast, (the exception
from e.2. applies to this case too), or from e.2 applies to this case too), or
(e.4) a packet sent as a link-layer broadcast, (the exception (e.5) a packet whose source address does not uniquely identify
from e.2., applies to this case too), or a single node -- e.g., the IPv6 Unspecified Address, an
IPv6 multicast address, or an address known by the ICMP
message sender to be an IPv6 anycast address.
(e.5) a packet whose source address does not uniquely identify a (f) Finally, to each sender of an erroneous data packet, an IPv6
single node -- e.g., the IPv6 Unspecified Address, or an node MUST limit the rate of ICMPv6 error messages sent, in order
IPv6 multicast address, or an IPv6 anycast address. to limit the bandwidth and forwarding costs incurred by the
error messages when a generator of erroneous packets does not
respond to those error messages by ceasing its transmissions.
(f) Finally, to each sender of an erroneous data packet, an IPv6 node There are a variety of ways of implementing the rate-limiting
MUST limit the rate of ICMPv6 error messages sent, in order to function, for example:
limit the bandwidth and forwarding costs incurred by the error
messages when a generator of erroneous packets does not respond
to those error messages by ceasing its transmissions. There are
a variety of ways of implementing the rate-limiting function, for
example:
(f.1) Timer-based - for example, limiting the rate of (f.1) Timer-based - for example, limiting the rate of
transmission of error messages to a given source, or to transmission of error messages to a given source, or to
any source, to at most once every T milliseconds. any source, to at most once every T milliseconds.
(f.2) Bandwidth-based - for example, limiting the rate at which (f.2) Bandwidth-based - for example, limiting the rate at
error messages are sent from a particular interface to which error messages are sent from a particular interface
some fraction F of the attached link's bandwidth. to some fraction F of the attached link's bandwidth.
The limit parameters (e.g., T or F in the above examples) MUST be The limit parameters (e.g., T or F in the above examples) MUST
configurable for the node, with a conservative default value be configurable for the node, with a conservative default value
(e.g., T = 1 second, NOT 0 seconds, or F = 2 percent, NOT 100 (e.g., T = 1 second, NOT 0 seconds, or F = 2 percent, NOT 100
percent). percent).
The following sections describe the message formats for the above The following sections describe the message formats for the above
ICMPv6 messages. ICMPv6 messages.
3. ICMPv6 Error Messages 3. ICMPv6 Error Messages
3.1 Destination Unreachable Message 3.1 Destination Unreachable Message
0 1 2 3 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 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 | | Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Unused | | Unused |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| As much of invoking packet | | As much of invoking packet |
+ as will fit without ICMPv6 packet + + as will fit without the ICMPv6 packet +
| exceeding 576 octets | | exceeding 576 octets |
+ +
| |
IPv6 Fields: IPv6 Fields:
Destination Address Destination Address
Copied from the Source Address field of the invoking Copied from the Source Address field of the invoking
packet. packet.
ICMPv6 Fields: ICMPv6 Fields:
Type 1 Type 1
Code 0 - no route to destination Code 0 - no route to destination
1 - communication with destination 1 - communication with destination
administratively prohibited administratively prohibited
skipping to change at page 10, line 45 skipping to change at page 8, line 41
Code 0 - no route to destination Code 0 - no route to destination
1 - communication with destination 1 - communication with destination
administratively prohibited administratively prohibited
2 - not a neighbor 2 - not a neighbor
3 - address unreachable 3 - address unreachable
4 - port unreachable 4 - port unreachable
Unused This field is unused for all code values. Unused This field is unused for all code values.
It must be initialized to zero by the sender It must be initialized to zero by the sender
and ignored by the receiver. and ignored by the receiver.
Description Description
A Destination Unreachable message SHOULD be generated by a router, or A Destination Unreachable message SHOULD be generated by a router, or
by the IPv6 layer in the originating node, in response to a packet by the IPv6 layer in the originating node, in response to a packet
that cannot be delivered to its destination address for reasons other that cannot be delivered to its destination address for reasons other
than congestion. (An ICMPv6 message MUST NOT be generated if a than congestion. (An ICMPv6 message MUST NOT be generated if a
packet is dropped due to congestion.) packet is dropped due to congestion.)
If the reason for the failure to deliver is lack of a matching entry If the reason for the failure to deliver is lack of a matching entry
in the forwarding node's routing table, the Code field is set to 0 in the forwarding node's routing table, the Code field is set to 0
(NOTE: this error can occur only in routers that do not hold a (NOTE: this error can occur only in nodes that do not hold a "default
"default route" in their routing tables). route" in their routing tables).
If the reason for the failure to deliver is administrative If the reason for the failure to deliver is administrative
prohibition, e.g., a "firewall filter", the Code field is set to 1. prohibition, e.g., a "firewall filter", the Code field is set to 1.
If the reason for the failure to deliver is that the next destination If the reason for the failure to deliver is that the next destination
address in the Routing header is not a neighbor of the processing address in the Routing header is not a neighbor of the processing
node but the "strict" bit is set for that address, then the Code node but the "strict" bit is set for that address, then the Code
field is set to 2. field is set to 2.
If there is any other reason for the failure to deliver, e.g., If there is any other reason for the failure to deliver, e.g.,
inability to resolve the IPv6 destination address into a inability to resolve the IPv6 destination address into a
corresponding link address, or a link-specific problem of some sort, corresponding link address, or a link-specific problem of some sort,
then the Code field is set to 3. then the Code field is set to 3.
A destination node SHOULD send a Destination Unreachable message with A destination node SHOULD send a Destination Unreachable message with
Code 4 in response to a packet for which the transport protocol Code 4 in response to a packet for which the transport protocol
(e.g., UDP) has no listener, if that transport protocol has no (e.g., UDP) has no listener, if that transport protocol has no
alternative means to inform the sender. alternative means to inform the sender.
Upper layer notification Upper layer notification
A node receiving the ICMPv6 Destination Unreachable message MUST A node receiving the ICMPv6 Destination Unreachable message MUST
notify the upper layer. notify the upper-layer protocol.
3.2 Packet Too Big Message 3.2 Packet Too Big Message
0 1 2 3 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 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 | | Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MTU | | MTU |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| As much of invoking packet | | As much of invoking packet |
+ as will fit without ICMPv6 packet + + as will fit without the ICMPv6 packet +
| exceeding 576 octets | | exceeding 576 octets |
+ +
| |
IPv6 Fields: IPv6 Fields:
Destination Address Destination Address
Copied from the Source Address field of the invoking Copied from the Source Address field of the invoking
packet. packet.
ICMPv6 Fields: ICMPv6 Fields:
Type 2 Type 2
Code 0 Code 0
MTU The Maximum Transmission Unit of the next-hop link. MTU The Maximum Transmission Unit of the next-hop link.
skipping to change at page 12, line 36 skipping to change at page 10, line 35
ICMPv6 Fields: ICMPv6 Fields:
Type 2 Type 2
Code 0 Code 0
MTU The Maximum Transmission Unit of the next-hop link. MTU The Maximum Transmission Unit of the next-hop link.
Description Description
A Packet Too Big MUST be sent by a router in response to a packet A Packet Too Big MUST be sent by a router in response to a packet
that it cannot forward because the packet is larger than the MTU of that it cannot forward because the packet is larger than the MTU of
the outgoing link. The information in this message is used as part the outgoing link. The information in this message is used as part
of the Path MTU Discovery process [RFC-1191]. of the Path MTU Discovery process [RFC-1191].
Sending a Packet Too Big Message makes an exception to one of the Sending a Packet Too Big Message makes an exception to one of the
rules of when to send an ICMPv6 error message, in that unlike other rules of when to send an ICMPv6 error message, in that unlike other
messages, it is sent in response to a packet received with an IPv6 messages, it is sent in response to a packet received with an IPv6
multicast destination address, or a link-layer multicast or link- multicast destination address, or a link-layer multicast or link-
layer broadcast address. layer broadcast address.
Upper layer notification Upper layer notification
An incoming Packet Too Big message MUST be passed to the upper layer. An incoming Packet Too Big message MUST be passed to the upper-layer
protocol.
3.3 Time Exceeded Message 3.3 Time Exceeded Message
0 1 2 3 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 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 | | Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Unused | | Unused |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| As much of invoking packet | | As much of invoking packet |
+ as will fit without ICMPv6 packet + + as will fit without the ICMPv6 packet +
| exceeding 576 octets | | exceeding 576 octets |
+ +
| |
IPv6 Fields: IPv6 Fields:
Destination Address Destination Address
Copied from the Source Address field of the invoking Copied from the Source Address field of the invoking
packet. packet.
ICMPv6 Fields: ICMPv6 Fields:
Type 3 Type 3
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Code 0 - hop limit exceeded in transit Code 0 - hop limit exceeded in transit
1 - fragment reassembly time exceeded 1 - fragment reassembly time exceeded
Unused This field is unused for all code values. Unused This field is unused for all code values.
It must be initialized to zero by the sender It must be initialized to zero by the sender
and ignored by the receiver. and ignored by the receiver.
Description Description
If a router receives a packet with a Hop Limit of zero, or a router If a router receives a packet with a Hop Limit of zero, or a router
decrements a packet's Hop Limit to zero, it MUST discard the packet decrements a packet's Hop Limit to zero, it MUST discard the packet
and send an ICMPv6 Time Exceeded message with Code 0 to the source of and send an ICMPv6 Time Exceeded message with Code 0 to the source of
the packet. This indicates either a routing loop or too small an the packet. This indicates either a routing loop or too small an
initial Hop Limit value. initial Hop Limit value.
The router sending an ICMPv6 Time Exceeded message with Code 0 SHOULD The router sending an ICMPv6 Time Exceeded message with Code 0 SHOULD
consider the receiving interface of the packet as the interface on consider the receiving interface of the packet as the interface on
which the packet forwarding failed in following rule (d) for which the packet forwarding failed in following rule (d) for
selecting the Source Address of the message. selecting the Source Address of the message.
IPv6 systems are expected to avoid fragmentation by implementing Path
MTU discovery. However, IPv6 defines an end-to-end fragmentation
function for backwards compatibility with existing higher-layer
protocols. All IPv6 implementations are required to support
reassembly of IPv6 fragments. There MUST be a reassembly timeout.
The reassembly timeout SHOULD be a fixed value. It is recommended
that this value lie between 60 and 120 seconds. If the timeout
expires, the partially-reassembled packet MUST be discarded. If the
fragment with offset zero was received during the reassembly time,
the destination host SHOULD also send an ICMPv6 Time Exceeded message
with Code 1 to the source of the fragment.
Upper layer notification Upper layer notification
An incoming Time Exceeded message MUST be passed to the upper layer. An incoming Time Exceeded message MUST be passed to the upper-layer
protocol.
3.4 Parameter Problem Message 3.4 Parameter Problem Message
0 1 2 3 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 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 | | Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Pointer | | Pointer |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| As much of invoking packet | | As much of invoking packet |
+ as will fit without ICMPv6 packet + + as will fit without the ICMPv6 packet +
| exceeding 576 octets | | exceeding 576 octets |
+ +
| |
IPv6 Fields: IPv6 Fields:
Destination Address Destination Address
Copied from the Source Address field of the invoking Copied from the Source Address field of the invoking
packet. packet.
ICMPv6 Fields: ICMPv6 Fields:
Type 4 Type 4
Code 0 - erroneous header field encountered Code 0 - erroneous header field encountered
1 - unrecognized Next Header type encountered 1 - unrecognized Next Header type encountered
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ICMPv6 Fields: ICMPv6 Fields:
Type 4 Type 4
Code 0 - erroneous header field encountered Code 0 - erroneous header field encountered
1 - unrecognized Next Header type encountered 1 - unrecognized Next Header type encountered
2 - unrecognized IPv6 option encountered 2 - unrecognized IPv6 option encountered
Pointer identifies the octet offset within the Pointer Identifies the octet offset within the
invoking packet where the error was detected. invoking packet where the error was detected.
The pointer will point beyond the end of the ICMPv6 The pointer will point beyond the end of the ICMPv6
packet if the field in error is beyond what can fit packet if the field in error is beyond what can fit
in the 576-byte limit of an ICMPv6 error message. in the 576-byte limit of an ICMPv6 error message.
Description Description
If an IPv6 node processing a packet finds a problem with a field in If an IPv6 node processing a packet finds a problem with a field in
the IPv6 header or extension headers such that it cannot complete the IPv6 header or extension headers such that it cannot complete
processing the packet, it MUST discard the packet and SHOULD send an processing the packet, it MUST discard the packet and SHOULD send an
ICMPv6 Parameter Problem message to the packet's source, indicating ICMPv6 Parameter Problem message to the packet's source, indicating
the type and location of the problem. the type and location of the problem.
The pointer identifies the octet of the original datagram's header The pointer identifies the octet of the original packet's header
where the error was detected. For example, an ICMPv6 message with where the error was detected. For example, an ICMPv6 message with
Type field = 4, Code field = 1, and Pointer field = 48 would indicate Type field = 4, Code field = 1, and Pointer field = 40 would indicate
that the IPv6 extension header following the IPv6 header of the that the IPv6 extension header following the IPv6 header of the
original datagram is holds an unrecognized Next Header field value. original packet holds an unrecognized Next Header field value.
Upper layer notification Upper layer notification
A node receiving this ICMPv6 message MUST notify the upper layer. A node receiving this ICMPv6 message MUST notify the upper-layer
protocol.
4. ICMPv6 Informational Messages 4. ICMPv6 Informational Messages
4.1 Echo Request Message 4.1 Echo Request Message
0 1 2 3 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 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 | | Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Identifier | Sequence Number | | Identifier | Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Data ... | Data ...
+-+-+-+-+- +-+-+-+-+-
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| Type | Code | Checksum | | Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Identifier | Sequence Number | | Identifier | Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Data ... | Data ...
+-+-+-+-+- +-+-+-+-+-
IPv6 Fields: IPv6 Fields:
Destination Address Destination Address
Any legal IPv6 address. Any legal IPv6 address.
ICMPv6 Fields: ICMPv6 Fields:
Type 128 Type 128
Code 0 Code 0
Identifier If code = 0, an identifier to aid in matching Identifier An identifier to aid in matching Echo Replies
Echo Replies to this Echo Request. May be zero. to this Echo Request. May be zero.
Sequence Number Sequence Number
If code = 0, a sequence number to aid in matching
Echo Replies to this Echo Request. May be zero.
Data If code = 0, zero or more octets of arbitrary data. A sequence number to aid in matching Echo Replies
to this Echo Request. May be zero.
Data Zero or more octets of arbitrary data.
Description Description
Every node MUST implement an ICMPv6 Echo responder function that Every node MUST implement an ICMPv6 Echo responder function that
receives Echo Requests and sends corresponding Echo Replies. A node receives Echo Requests and sends corresponding Echo Replies. A node
SHOULD also implement an application-layer interface for sending Echo SHOULD also implement an application-layer interface for sending Echo
Requests and receiving Echo Replies, for diagnostic purposes. Requests and receiving Echo Replies, for diagnostic purposes.
Upper layer notification Upper layer notification
A node receiving this ICMPv6 message MAY notify the upper layer. A node receiving this ICMPv6 message MAY notify the upper-layer
protocol.
4.2 Echo Reply Message 4.2 Echo Reply Message
0 1 2 3 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 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 | | Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Identifier | Sequence Number | | Identifier | Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Data ... | Data ...
+-+-+-+-+- +-+-+-+-+-
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| Type | Code | Checksum | | Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Identifier | Sequence Number | | Identifier | Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Data ... | Data ...
+-+-+-+-+- +-+-+-+-+-
IPv6 Fields: IPv6 Fields:
Destination Address Destination Address
Copied from the Source Address field of the invoking Copied from the Source Address field of the invoking
Echo Request packet. Echo Request packet.
ICMPv6 Fields: ICMPv6 Fields:
Type 129 Type 129
Code 0 Code 0
Identifier If code = 0, the identifier from the invoking Identifier The identifier from the invoking Echo Request message.
Echo Request message.
Sequence If code = 0, the sequence number from the invoking Sequence The sequence number from the invoking Echo Request
Number Echo Request message. Number message.
Data If code = 0, the data from the invoking Data The data from the invoking Echo Request message.
Echo Request message
Description Description
Every node MUST implement an ICMPv6 Echo responder function that Every node MUST implement an ICMPv6 Echo responder function that
receives Echo Requests and sends corresponding Echo Replies. A node receives Echo Requests and sends corresponding Echo Replies. A node
SHOULD also implement an application-layer interface for sending Echo SHOULD also implement an application-layer interface for sending Echo
Requests and receiving Echo Replies, for diagnostic purposes. Requests and receiving Echo Replies, for diagnostic purposes.
The source address of an Echo Reply sent in response to a unicast The source address of an Echo Reply sent in response to a unicast
Echo Request message MUST be the same as the destination address of Echo Request message MUST be the same as the destination address of
that Echo Request message. that Echo Request message.
An Echo Reply SHOULD be sent in response to an Echo Request message An Echo Reply SHOULD be sent in response to an Echo Request message
sent to an IPv6 multicast address. The source address of the reply sent to an IPv6 multicast address. The source address of the reply
MUST be a unicast address belonging to the interface on which the MUST be a unicast address belonging to the interface on which the
multicast Echo Request message was received. multicast Echo Request message was received.
The data received in the ICMPv6 Echo Request message MUST be returned The data received in the ICMPv6 Echo Request message MUST be returned
entirely and unmodified in the ICMPv6 Echo Reply message, unless the entirely and unmodified in the ICMPv6 Echo Reply message, unless the
Echo Reply would exceed the MTU of the path back to the Echo Echo Reply would exceed the MTU of the path back to the Echo
requester, in which case the data is truncated to fit that path MTU. requester, in which case the data is truncated to fit that path MTU.
Upper layer notification Upper layer notification
Echo Reply messages MUST be passed to the ICMPv6 user interface, Echo Reply messages MUST be passed to the ICMPv6 user interface,
unless the corresponding Echo Request originated in the IP layer. unless the corresponding Echo Request originated in the IP layer.
4.3 Group Membership Messages 4.3 Group Membership Messages
The ICMPv6 Group Membership Messages have the following format: The ICMPv6 Group Membership Messages have the following format:
0 1 2 3 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 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 | | Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Maximum Response Delay | Unused | | Maximum Response Delay | Unused |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
skipping to change at page 18, line 45 skipping to change at page 17, line 28
| Multicast | | Multicast |
+ + + +
| Address | | Address |
+ + + +
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
IPv6 Fields: IPv6 Fields:
Destination Address Destination Address
In a Group Membership Query message, the multicast In a Group Membership Query message, the multicast
address of the group being queried, or the Link-Local address of the group being queried, or the Link-Local
All-Nodes multicast address. All-Nodes multicast address.
In a Group Membership Report or a Group Membership In a Group Membership Report or a Group Membership
Termination message, the multicast address of the Reduction message, the multicast address of the
group being reported or terminated. group being reported or terminated.
Hop Limit 1 Hop Limit 1
ICMPv6 Fields: ICMPv6 Fields:
Type 130 - Group Membership Query Type 130 - Group Membership Query
131 - Group Membership Report 131 - Group Membership Report
132 - Group Membership Termination 132 - Group Membership Reduction
Code 0 Code 0
Maximum Response Delay Maximum Response Delay
In Query messages, the maximum time that responding In Query messages, the maximum time that responding
Report messages may be delayed, in milliseconds. Report messages may be delayed, in milliseconds.
In Report and Termination messages, this field is In Report and Reduction messages, this field is
is initialized to zero by the sender and ignored by is initialized to zero by the sender and ignored by
receivers. receivers.
Unused Initialized to zero by the sender; ignored by receivers. Unused Initialized to zero by the sender; ignored by receivers.
Multicast Address Multicast Address
The address of the multicast group about which the The address of the multicast group about which the
message is being sent. In Query messages, the Multicast message is being sent. In Query messages, the Multicast
Address field may be zero, implying a query for all Address field may be zero, implying a query for all
groups. groups.
Description Description
The ICMPv6 Group Membership messages are used to convey information The ICMPv6 Group Membership messages are used to convey information
about multicast group membership from nodes to their neighboring about multicast group membership from nodes to their neighboring
routers. The details of their usage is given in [RFC-1112]. routers. The details of their usage is given in [RFC-1112].
5. References 5. References
[IPv6]S. Deering, R. Hinden, "Internet Protocol, Version 6, [IPv6] Deering, S., and R. Hinden, "Internet Protocol, Version
Specification", April 1995 6, Specification", RFC 1883, Xerox PARC, Ipsilon
Networks, December 1995.
[IPv6-ADDR] [IPv6-ADDR] Hinden, R., and S. Deering, Editors, "IP Version 6
R. Hinden, "IP Version 6 Addressing Architecture", April 1995 Addressing Architecture", RFC 1884, Ipsilon Networks,
Xerox PARC, December 1995.
[IPv6-DISC] [IPv6-DISC] Narten, T., Nordmark, E., and W. Simpson, "Neighbor
W. A. Simpson, "IPv6 Neighbor Discovery", April 1995 Discovery for IP Version 6 (IPv6)", Work in Progress.
[RFC-792] [RFC-792] Postel, J., "Internet Control Message Protocol", STD 5,
J. Postel, "Internet Control Message Protocol", RFC 792. RFC 792, USC/Information Sciences Institute, September
1981.
[RFC-1112] [RFC-1112] Deering, S., "Host Extensions for IP Multicasting", STD
S. Deering, "Host Extensions for IP Multicasting", RFC 1112. 5, RFC 1112, Stanford University, August 1989.
[RFC-1122] [RFC-1122] Braden, R., "Requirements for Internet Hosts -
R. Braden, "Requirements for Internet Hosts - Communication Communication Layers", STD 3, RFC 1122, USC/Information
Layers", RFC 1122. Sciences Institute, October 1989.
[RFC-1191] [RFC-1191] Mogul, J., and S. Deering, "Path MTU Discovery", RFC
J. Mogul and S. Deering, "Path MTU Discovery", RFC 1191. 1191, DECWRL, Stanford University, November 1990.
6. Acknowledgements 6. Acknowledgements
The document is derived from previous ICMP drafts of the SIPP and The document is derived from previous ICMP drafts of the SIPP and
IPng working group. IPng working group.
The IPng working group and particularly Robert Elz, Jim Bound, Bill The IPng working group and particularly Robert Elz, Jim Bound, Bill
Simpson, Thomas Narten, Charlie Lynn, Bill Fink, and Scott Bradner Simpson, Thomas Narten, Charlie Lynn, Bill Fink, and Scott Bradner
(in chronological order) provided extensive review information and (in chronological order) provided extensive review information and
feedback. feedback.
7. Security Considerations 7. Security Considerations
Security considerations are not discussed in this memo. Security issues are not discussed in this memo.
Authors' Addresses: Authors' Addresses:
Alex Conta Stephen Deering Alex Conta Stephen Deering
Digital Equipment Corporation Xerox Palo Alto Research Center Digital Equipment Corporation Xerox Palo Alto Research Center
110 Spitbrook Rd 3333 Coyote Hill Road 110 Spitbrook Rd 3333 Coyote Hill Road
Nashua, NH 03062 Palo Alto, CA 94304 Nashua, NH 03062 Palo Alto, CA 94304
+1-603-881-0744 +1-415-812-4839
email: conta@zk3.dec.com email: deering@parc.xerox.com Phone: +1-603-881-0744 Phone: +1-415-812-4839
EMail: conta@zk3.dec.com EMail: deering@parc.xerox.com
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