Internet Assigned Numbers Authority

Internet Control Message Protocol (ICMP) Parameters

Last Updated
2024-12-06
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Registries included below

ICMP Type Numbers

Registration Procedure(s)
IESG Approval or Standards Action
Reference
[RFC2780]
Note
The Internet Control Message Protocol (ICMP) has many messages that
are identified by a "type" field.
Available Formats

CSV
Type Name Reference
0 Echo Reply [RFC792]
1 Unassigned
2 Unassigned
3 Destination Unreachable [RFC792]
4 Source Quench (Deprecated) [RFC792][RFC6633]
5 Redirect [RFC792]
6 Alternate Host Address (Deprecated) [RFC6918]
7 Unassigned
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 (Deprecated) [RFC792][RFC6918]
16 Information Reply (Deprecated) [RFC792][RFC6918]
17 Address Mask Request (Deprecated) [RFC950][RFC6918]
18 Address Mask Reply (Deprecated) [RFC950][RFC6918]
19 Reserved (for Security) [Solo]
20-29 Reserved (for Robustness Experiment) [ZSu]
30 Traceroute (Deprecated) [RFC1393][RFC6918]
31 Datagram Conversion Error (Deprecated) [RFC1475][RFC6918]
32 Mobile Host Redirect (Deprecated) [David_Johnson][RFC6918]
33 IPv6 Where-Are-You (Deprecated) [Simpson][RFC6918]
34 IPv6 I-Am-Here (Deprecated) [Simpson][RFC6918]
35 Mobile Registration Request (Deprecated) [Simpson][RFC6918]
36 Mobile Registration Reply (Deprecated) [Simpson][RFC6918]
37 Domain Name Request (Deprecated) [RFC1788][RFC6918]
38 Domain Name Reply (Deprecated) [RFC1788][RFC6918]
39 SKIP (Deprecated) [Markson][RFC6918]
40 Photuris [RFC2521]
41 ICMP messages utilized by experimental mobility protocols such as Seamoby [RFC4065]
42 Extended Echo Request [RFC8335]
43 Extended Echo Reply [RFC8335]
44-252 Unassigned
253 RFC3692-style Experiment 1 [RFC4727]
254 RFC3692-style Experiment 2 [RFC4727]
255 Reserved [JBP]

Code Fields

Reference
[RFC2780]
Note
Many of these ICMP types have a "code" field.  Here we list the types
again with their assigned code fields.
    

Type 0 — Echo Reply

Registration Procedure(s)
IESG Approval or Standards Action
Reference
[RFC792][RFC2780]
Available Formats

CSV
Codes Description Reference
0 No Code

Type 1 — Unassigned

Codes Description Reference
No registrations at this time.

Type 2 — Unassigned

Codes Description Reference
No registrations at this time.

Type 3 — Destination Unreachable

Registration Procedure(s)
IESG Approval or Standards Action
Reference
[RFC792][RFC2780]
Available Formats

CSV
Codes Description Reference
0 Net Unreachable [RFC792]
1 Host Unreachable [RFC792]
2 Protocol Unreachable [RFC792]
3 Port Unreachable [RFC792]
4 Fragmentation Needed and Don't 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 Network is Administratively Prohibited [RFC1122]
10 Communication with Destination Host is Administratively Prohibited [RFC1122]
11 Destination Network Unreachable for Type of Service [RFC1122]
12 Destination Host Unreachable for Type of Service [RFC1122]
13 Communication Administratively Prohibited [RFC1812]
14 Host Precedence Violation [RFC1812]
15 Precedence cutoff in effect [RFC1812]

Type 4 — Source Quench (Deprecated)

Reference
[RFC792][RFC6633]
Available Formats

CSV
Codes Description Reference
0 No Code

Type 5 — Redirect

Registration Procedure(s)
IESG Approval or Standards Action
Reference
[RFC792][RFC2780]
Available Formats

CSV
Codes Description Reference
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

Type 6 — Alternate Host Address (Deprecated)

Reference
[JBP][RFC6918]
Available Formats

CSV
Codes Description Reference
0 Alternate Address for Host

Type 7 — Unassigned

Codes Description Reference
No registrations at this time.

Type 8 — Echo

Registration Procedure(s)
IESG Approval or Standards Action
Reference
[RFC792][RFC2780]
Available Formats

CSV
Codes Description Reference
0 No Code

Type 9 — Router Advertisement

Registration Procedure(s)
IESG Approval or Standards Action
Reference
[RFC1256][RFC2780]
Available Formats

CSV
Codes Description Reference
0 Normal router advertisement [RFC3344]
16 Does not route common traffic [RFC3344]

Type 10 — Router Selection

Registration Procedure(s)
IESG Approval or Standards Action
Reference
[RFC1256][RFC2780]
Available Formats

CSV
Codes Description Reference
0 No Code

Type 11 — Time Exceeded

Registration Procedure(s)
IESG Approval or Standards Action
Reference
[RFC792][RFC2780]
Available Formats

CSV
Codes Description Reference
0 Time to Live exceeded in Transit
1 Fragment Reassembly Time Exceeded

Type 12 — Parameter Problem

Registration Procedure(s)
IESG Approval or Standards Action
Reference
[RFC792][RFC2780]
Available Formats

CSV
Codes Description Reference
0 Pointer indicates the error
1 Missing a Required Option [RFC1108]
2 Bad Length

Type 13 — Timestamp

Registration Procedure(s)
IESG Approval or Standards Action
Reference
[RFC792][RFC2780]
Available Formats

CSV
Codes Description Reference
0 No Code

Type 14 — Timestamp Reply

Registration Procedure(s)
IESG Approval or Standards Action
Reference
[RFC792][RFC2780]
Available Formats

CSV
Codes Description Reference
0 No Code

Type 15 — Information Request (Deprecated)

Reference
[RFC792][RFC6918]
Available Formats

CSV
Codes Description Reference
0 No Code

Type 16 — Information Reply (Deprecated)

Reference
[RFC792][RFC6918]
Available Formats

CSV
Codes Description Reference
0 No Code

Type 17 — Address Mask Request (Deprecated)

Reference
[RFC950][RFC6918]
Available Formats

CSV
Codes Description Reference
0 No Code

Type 18 — Address Mask Reply (Deprecated)

Reference
[RFC950][RFC6918]
Available Formats

CSV
Codes Description Reference
0 No Code

Type 19 — Reserved (for Security)

Reference
[Solo]
Codes Description Reference
No registrations at this time.

Types 20-29 — Reserved (for Robustness Experiment)

Reference
[ZSu]
Codes Description Reference
No registrations at this time.

Type 30 — Traceroute (Deprecated)

Reference
[RFC1393][RFC6918]
Codes Description Reference
No registrations at this time.

Type 31 — Datagram Conversion Error (Deprecated)

Reference
[RFC1475][RFC6918]
Codes Description Reference
No registrations at this time.

Type 32 — Mobile Host Redirect (Deprecated)

Reference
[David_Johnson][RFC6918]
Codes Description Reference
No registrations at this time.

Type 33 — IPv6 Where-Are-You (Deprecated)

Reference
[Simpson][RFC6918]
Codes Description Reference
No registrations at this time.

Type 34 — IPv6 I-Am-Here (Deprecated)

Reference
[Simpson][RFC6918]
Codes Description Reference
No registrations at this time.

Type 35 — Mobile Registration Request (Deprecated)

Reference
[Simpson][RFC6918]
Codes Description Reference
No registrations at this time.

Type 36 — Mobile Registration Reply (Deprecated)

Reference
[Simpson][RFC6918]
Codes Description Reference
No registrations at this time.

Type 37 — Domain Name Request (Deprecated)

Reference
[RFC1788][RFC6918]
Codes Description Reference
No registrations at this time.

Type 38 — Domain Name Reply (Deprecated)

Reference
[RFC1788][RFC6918]
Codes Description Reference
No registrations at this time.

Type 39 — SKIP (Deprecated)

Reference
[Markson][RFC6918]
Codes Description Reference
No registrations at this time.

Type 40 — Photuris

Registration Procedure(s)
IESG Approval or Standards Action
Reference
[RFC2521][RFC2780]
Available Formats

CSV
Codes Description Reference
0 Bad SPI
1 Authentication Failed
2 Decompression Failed
3 Decryption Failed
4 Need Authentication
5 Need Authorization

Type 41 — ICMP messages utilized by experimental mobility protocols such as Seamoby

Registration Procedure(s)
Specification Required or IESG Approval
Expert(s)
Unassigned
Reference
[RFC4065]
Codes Description Reference
No registrations at this time.

Type 42 — Extended Echo Request

Registration Procedure(s)
First Come First Served
Reference
[RFC8335]
Available Formats

CSV
Codes Description Reference
0 No Error [RFC8335]
1-255 Unassigned

Type 43 — Extended Echo Reply

Registration Procedure(s)
First Come First Served
Reference
[RFC8335]
Available Formats

CSV
Codes Description Reference
0 No Error [RFC8335]
1 Malformed Query [RFC8335]
2 No Such Interface [RFC8335]
3 No Such Table Entry [RFC8335]
4 Multiple Interfaces Satisfy Query [RFC8335]
5-255 Unassigned

Types 44-252 — Unassigned

Codes Description Reference
No registrations at this time.

Type 253 — RFC3692-style Experiment 1 [1]

Registration Procedure(s)
Standards Action or IESG Approval
Reference
[RFC4727]
Codes Description Reference
No registrations at this time.

Type 254 — RFC3692-style Experiment 2 [1]

Registration Procedure(s)
Standards Action or IESG Approval
Reference
[RFC4727]
Codes Description Reference
No registrations at this time.

ICMP Extension Object Classes and Class Sub-types

Reference
[RFC4884]
Available Formats

CSV
Range Registration Procedures
0-246 First Come First Served
247-255 Private Use
Class Value Class Name Reference
1 MPLS Label Stack Class [RFC4950]
2 Interface Information Object [RFC5837]
3 Interface Identification Object [RFC8335]
4 Extended Information [RFC8883]
5 Node Identification Object [draft-fenner-intarea-extended-icmp-hostid-01]
6-246 Unassigned
247-255 Reserved for Private Use [RFC4884]

Sub-types — Class 1 — MPLS Label Stack Class

Registration Procedure(s)
First Come First Served
Reference
[RFC4950]
Available Formats

CSV
C-Type (Value) Description Reference
0 Reserved [RFC4950]
1 Incoming MPLS Label Stack [RFC4950]
2-246 Unassigned
247-255 Reserved for private use [RFC4950]

Sub-types — Class 2 — Interface Information Object

Reference
[RFC5837]
Available Formats

CSV
C-Type (Value) Description Reference
0-1 Interface Role field [RFC5837]
2 Unallocated - allocatable with Standards Action [RFC5837]
3 Unallocated - allocatable with Standards Action [RFC5837]
4 ifIndex included [RFC5837]
5 IP Address Sub-object included [RFC5837]
6 Name Sub-object included [RFC5837]
7 MTU included [RFC5837]

Sub-types — Class 2 — Interface Information Object — Interface Roles

Available Formats

CSV
Value Description Reference
0 Incoming IP Interface [RFC5837]
1 Sub-IP Component of Incoming IP Interface [RFC5837]
2 Outgoing IP Interface [RFC5837]
3 IP Next-hop [RFC5837]

Sub-types — Class 3 — Interface Identification Object

Registration Procedure(s)
First Come First Served
Reference
[RFC8335]
Available Formats

CSV
Codes Description Reference
0 Reserved [RFC8335]
1 Identifies Interface By Name [RFC8335]
2 Identifies Interface By Index [RFC8335]
3 Identifies Interface By Address [RFC8335]
4-255 Unassigned

Sub-types — Class 4 — Extended Information

Registration Procedure(s)
Standards Action
Reference
[RFC8883]
Available Formats

CSV
Value Description Reference
0 Reserved [RFC8883]
1 Pointer [RFC8883]

Contact Information

ID Name Contact URI Last Updated
[JBP] Jon Postel mailto:postel&isi.edu 1995-09
[David_Johnson] David Johnson
[Markson] Tom Markson mailto:markson&osmosys.incog.com 1995-09
[Simpson] Bill Simpson mailto:Bill.Simpson&um.cc.umich.edu 1995-10
[Solo]
[ZSu] Zaw-Sing Su mailto:ZSu&TSCA.ISTC.SRI.COM

Footnote

[1]
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.