ICMPv6, Internet Control Message Protocol for IPv6

Protocol suite:	TCP/IP.
Protocol type:	Transport layer control protocol.
IP Protocol:	58.
Related protocols:	MLD, Multicast Listener Discovery. MRD, Multicast Router Discovery. SEND, SEcure Neighbor Discovery.
SNMP MIBs:	iso.org.dod.internet.mgmt.mib-2.ipv6IcmpMIB (1.3.6.1.2.1.56).
Working groups:	ipv6, IP Version 6 Working Group.
Links:	IANA: ICMPv6 parameters.

RFC 2463:

IPv6 uses the Internet Control Message Protocol (ICMP) as defined for IPv4 with a number of changes. The resulting protocol is called ICMPv6.

MAC header

IPv6 header

ICMPv6 header

ICMPv6 message :::

ICMPv6 header:

00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Type								Code								Checksum
ICMPv6 message :::

Type. 8 bits.
Specifies the format of the message.

Type	Description	References
0
1	Destination unreachable.	RFC 2463, RFC 4443
2	Packet too big.	RFC 2463, RFC 4443
3	Time exceeded.	RFC 2463, RFC 4443
4	Parameter problem.	RFC 2463, RFC 4443
5 - 99
100 101	Private experimentation.	RFC 4443
102 - 126
127	reserved for expansion of ICMPv6 error messages.	RFC 4443
128	Echo request.	RFC 2463, RFC 4443
129	Echo reply.	RFC 2463, RFC 4443
130	Group Membership Query.	RFC 2710
131	Group Membership Report.	RFC 2710
132	Group Membership Reduction.	RFC 2710
133	Router Solicitation.	RFC 2461
134	Router Advertisement.	RFC 2461
135	Neighbor Solicitation.	RFC 2461
136	Neighbor Advertisement.	RFC 2461
137	Redirect.	RFC 2461
138	Router Renumbering.	RFC 2894
139	ICMP Node Information Query.	RFC 4620
140	ICMP Node Information Response.	RFC 4620
141	Inverse Neighbor Discovery Solicitation Message.	RFC 3122
142	Inverse Neighbor Discovery Advertisement Message.	RFC 3122
143	MLDv2 Multicast Listener Report.	RFC 3810
144	Home Agent Address Discovery Request Message.	RFC 3775
145	Home Agent Address Discovery Reply Message	RFC 3775
146	Mobile Prefix Solicitation.	RFC 3775
147	Mobile Prefix Advertisement	RFC 3775
148	Certification Path Solicitation.	RFC 3971
149	Certification Path Advertisement.	RFC 3971
150	Experimental mobility protocols.	RFC 4065
151	MRD, Multicast Router Advertisement.	RFC 4286
152	MRD, Multicast Router Solicitation.	RFC 4286
153	MRD, Multicast Router Termination.	RFC 4286
154	FMIPv6 messages.	RFC 5568
155 - 199
200 201	Private experimentation.	RFC 4443
202 - 254
255	reserved for expansion.	RFC 4443

Code. 8 bits.
Further qualifies the ICMPv6 message.

Checksum. 16 bits.
Checksum that covers the ICMPv6 message. This field contains the 16-bit one's complement of the one's complement sum of the entire ICMPv6 message starting with the ICMPv6 message type field, prepended with a pseudo-header of IPv6 header fields. The pseudo-header contains the following fields:

00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Source IPv6 address :::
Destination IPv6 address :::
Upper layer packet length
0																								Next header

ICMPv6 message. Variable length.
Contains the data specific to the message type indicated by the Type and Code fields.

Glossary:

RFCs:

[RFC 1933] Transition Mechanisms for IPv6 Hosts and Routers.

[RFC 2460] Internet Protocol, Version 6 (IPv6) Specification.

Obsoletes: RFC 1883.

[RFC 2461] Neighbor Discovery for IP Version 6 (IPv6).

Updated by: RFC 4311.
Obsoletes: RFC 1970.

[RFC 2473] Generic Packet Tunneling in IPv6 Specification.

[RFC 2765] Stateless IP/ICMP Translation Algorithm (SIIT).

[RFC 2780] IANA Allocation Guidelines For Values In the Internet Protocol and Related Headers.

BCP: 37.
Updated by:
RFC 4443, RFC 5237.

[RFC 2894] Router Renumbering for IPv6.

[RFC 3122] Extensions to IPv6 Neighbor Discovery for Inverse Discovery Specification.

[RFC 3775] Mobility Support in IPv6.

Defines IPv6 protocol 135 (Mobility Header).
Defines ICMPv6 messages 144, 145, 146, 147.

[RFC 3971] SEcure Neighbor Discovery (SEND).

Category: Standards Track.
Defines ICMPv6 messages 148 (Certification Path Solicitation), 149 (Certification Path Advertisement).

[RFC 4191] Default Router Preferences and More-Specific Routes.

Category: Standards Track.
Defines Neighbor Discovery option 24 (Route Information Option).

[RFC 4286] Multicast Router Discovery.

Category: Standards Track.
Defines ICMPv6 messages 151 (Multicast Router Advertisement), 152 (Multicast Router Solicitation) and 153 (Multicast Router Termination).
Defines IGMP messages 0x30 (Multicast Router Advertisement), 0x31 (Multicast Router Solicitation) and 0x32 (Multicast Router Termination).
Defines multicast addresses 224.0.0.106 (All-Snoopers) and FF02:0:0:0:0:0:0:6A (All-Snoopers).

[RFC 4301] Security Architecture for the Internet Protocol.

Category: Standards Track.
Obsoletes:
RFC 2401.

[RFC 4443] Internet Control Message Protocol (ICMPv6) for the Internet Protocol Version 6 (IPv6) Specification.

Category: Standards Track.
Obsoletes:
RFC 2463.
Updates:
RFC 2780.

[RFC 5568] Mobile IPv6 Fast Handovers.

Category: Standards Track.
Defines ICMPv6 message 154 (FMIPv6 messages).
Defines Mobility Header messages 14 (Handover Initiate), 15 (Handover Acknowledge).
Defines Mobility Header option 34 (IPv6 Address/Prefix).
Obsoletes:
RFC 5268.

Publications:

Obsolete RFCs:

[RFC 1883] Internet Protocol, Version 6 (IPv6) Specification.