ICMP TYPE NUMBERS
(last updated 2008-02-13)
Registries included below:
- ICMP Type Numbers
- Code Fields
- ICMP Extension Objects Classes
The Internet Control Message Protocol (ICMP) has many messages that
are identified by a "type" field.
Type Name Reference
---- ------------------------- ---------
0 Echo Reply [RFC792]
1 Unassigned [JBP]
2 Unassigned [JBP]
3 Destination Unreachable [RFC792]
4 Source Quench [RFC792]
5 Redirect [RFC792]
6 Alternate Host Address [JBP]
7 Unassigned [JBP]
8 Echo [RFC792]
9 Router Advertisement [RFC1256]
10 Router Solicitation [RFC1256]
11 Time Exceeded [RFC792]
12 Parameter Problem [RFC792]
13 Timestamp [RFC792]
14 Timestamp Reply [RFC792]
15 Information Request [RFC792]
16 Information Reply [RFC792]
17 Address Mask Request [RFC950]
18 Address Mask Reply [RFC950]
19 Reserved (for Security) [Solo]
20-29 Reserved (for Robustness Experiment) [ZSu]
30 Traceroute [RFC1393]
31 Datagram Conversion Error [RFC1475]
32 Mobile Host Redirect [David Johnson]
33 IPv6 Where-Are-You [Bill Simpson]
34 IPv6 I-Am-Here [Bill Simpson]
35 Mobile Registration Request [Bill Simpson]
36 Mobile Registration Reply [Bill Simpson]
37 Domain Name Request [RFC1788]
38 Domain Name Reply [RFC1788]
39 SKIP [Markson]
40 Photuris [RFC2521]
41 ICMP messages utilized by experimental [RFC4065]
mobility protocols such as Seamoby
42-255 Reserved [JBP]
Many of these ICMP types have a "code" field. Here we list the types
again with their assigned code fields.
Type Name Reference
---- ------------------------- ---------
0 Echo Reply [RFC792]
Codes
0 No Code
1 Unassigned [JBP]
2 Unassigned [JBP]
3 Destination Unreachable [RFC792]
Codes
0 Net Unreachable [RFC792]
1 Host Unreachable [RFC792]
2 Protocol Unreachable [RFC792]
3 Port Unreachable [RFC792]
4 Fragmentation Needed and Don't [RFC792]
Fragment was Set [RFC792]
5 Source Route Failed [RFC792]
6 Destination Network Unknown [RFC1122]
7 Destination Host Unknown [RFC1122]
8 Source Host Isolated [RFC1122]
9 Communication with Destination [RFC1122]
Network is Administratively Prohibited
10 Communication with Destination Host is [RFC1122]
Administratively Prohibited
11 Destination Network Unreachable for Type [RFC1122]
of Service
12 Destination Host Unreachable for Type of [RFC1122]
Service
13 Communication Administratively Prohibited [RFC1812]
14 Host Precedence Violation [RFC1812]
15 Precedence cutoff in effect [RFC1812]
4 Source Quench [RFC792]
Codes
0 No Code
5 Redirect [RFC792]
Codes
0 Redirect Datagram for the Network (or subnet)
1 Redirect Datagram for the Host
2 Redirect Datagram for the Type of Service and Network
3 Redirect Datagram for the Type of Service and Host
6 Alternate Host Address [JBP]
Codes
0 Alternate Address for Host
7 Unassigned [JBP]
8 Echo [RFC792]
Codes
0 No Code
9 Router Advertisement [RFC1256]
Codes
0 Normal router advertisement
16 Does not route common traffic [RFC2002]
10 Router Selection [RFC1256]
Codes
0 No Code
11 Time Exceeded [RFC792]
Codes
0 Time to Live exceeded in Transit
1 Fragment Reassembly Time Exceeded
12 Parameter Problem [RFC792]
Codes
0 Pointer indicates the error
1 Missing a Required Option [RFC1108]
2 Bad Length
13 Timestamp [RFC792]
Codes
0 No Code
14 Timestamp Reply [RFC792]
Codes
0 No Code
15 Information Request [RFC792]
Codes
0 No Code
16 Information Reply [RFC792]
Codes
0 No Code
17 Address Mask Request [RFC950]
Codes
0 No Code
18 Address Mask Reply [RFC950]
Codes
0 No Code
19 Reserved (for Security) [Solo]
20-29 Reserved (for Robustness Experiment) [ZSu]
30 Traceroute [RFC1393]
31 Datagram Conversion Error [RFC1475]
32 Mobile Host Redirect [David Johnson]
33 IPv6 Where-Are-You [Bill Simpson]
34 IPv6 I-Am-Here [Bill Simpson]
35 Mobile Registration Request [Bill Simpson]
36 Mobile Registration Reply [Bill Simpson]
39 SKIP [Markson]
40 Photuris [RFC2521]
Codes
0 = Bad SPI
1 = Authentication Failed
2 = Decompression Failed
3 = Decryption Failed
4 = Need Authentication
5 = Need Authorization
41-252 Unassigned
253 RFC3692-style Experiment 1 (*) [RFC4727]
254 RFC3692-style Experiment 2 (*) [RFC4727]
(*) It is only appropriate to use these values in explicitly-
configured experiments; they MUST NOT be shipped as defaults in
implementations. See RFC 3692 for details.
ICMP Extension Objects Classes and Class Sub-types - per [RFC4884]
Registration Procedures:
0-246 First Come First Serve
247-255 Private Use
Object
Class
Value Class Name Reference
------ -------------------------- ---------
1 MPLS Label Stack Class [RFC4950]
Sub-types [RFC4950]
C-Type
0 Reserved [RFC4950]
1 Incoming MPLS Label Stack [RFC4950]
0x02-0xF6 Available for assignment [RFC4950]
0xF7-0xFF Reserved for private use [RFC4950]
Allocation Policy: C-Type values for Class-num 1 are
assignable on a first-come-first-serve (FCFS) basis
[RFC2434].
REFERENCES
----------
[RFC792] Postel, J., "Internet Control Message Protocol", STD 5,
RFC 792, USC/Information Sciences Institute, September 1981.
[RFC950] Mogul, J., and J. Postel, "Internet Standard Subnetting
Procedure", STD 5, RFC 950, Stanford, USC/Information
Sciences Institute, August 1985.
[RFC1108] Kent, S., "U.S. Department of Defense Security Options for
the Internet Protocol", RFC 1108, November 1991.
[RFC1122] R. Braden, Ed., "Requirements for Internet Hosts --
Communication Layers", RFC 1122, October 1989.
[RFC1256] Deering, S., Editor, "ICMP Router Discovery Messages",
RFC 1256, Xerox PARC, September 1991.
[RFC1393] Malkin, G., "Traceroute Using an IP Option", RFC 1393,
Xylogics, Inc., January 1993.
[RFC1475] Ullmann, R., "TP/IX: The Next Internet", RFC 1475, Process
Software Corporation, June 1993.
[RFC1788] W. Simpson, "ICMP Domain Name Messages", RFC 1788, April 1995.
[RFC1812] Baker, F., "Requirements for IP Version 4 Routers", RFC 1812,
Cisco Systems, June 1995.
[RFC2002] C. Perkins, Editor, "IP Mobility Support", RFC 2002,
October 1996.
[RFC2434] T. Narten and H. Alvestrand, "Guidelines for Writing
an IANA Considerations Section in RFCs", RFC 2434, October 1998.
[RFC2521] P. Karn and W. Simpson, "ICMP Security Failures Messages",
RFC 2521, March 1999.
[RFC4065] J. Kempf, "Instructions for Seamoby and Experimental
Mobility Protocol IANA", RFC 4065, July 2005.
[RFC4727] B. Fenner, "Experimental values In IPv4, IPv6, ICMPv4, ICMPv6,
UDP and TCP Headers", RFC 4727, November 2006.
[RFC4884] R. Bonica, D. Gan, P. Nikander, D. Tappan and C. Pignataro,
"Extended ICMP to Support Multi-part Messages", RFC 4884,
April 2007.
[RFC4950] R. Bonica, D. Gan, D. Tappan and C. Pignataro, "ICMP Extensions for
MultiProtocol Label Switching", RFC 4950, August 2007.
PEOPLE
------
[JBP] Jon Postel, , September 1995.
[David Johnson]
[Markson] Tom Markson, , September 1995.
[Simpson] Bill Simpson, , October 1995.
[Solo]
[ZSu] Zaw-Sing Su
[]
