Appendix C. Lists of Reserved Ports, ICMP Types and Codes, and Internet Protocols

Type

Name

Reference

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

[Simpson]

38

Domain Name Reply

[Simpson]

39

SKIP

[Markson]

40

Photuris

[RFC2521]

41-255

Reserved

[JBP]

ICMP codes

Some ICMP types have codes attached.

ICMP type

Name

Code

Description

0

Echo Reply

0

No Code

1

Unassigned

 

 

2

Unassigned

 

 

3

Destination Unreachable

0

Net Unreachable

 

 

1

Host Unreachable

 

 

2

Protocol Unreachable

 

 

3

Port Unreachable

 

 

4

Fragmentation Needed and

 

 

 

Don’t Fragment was Set

 

 

5

Source Route Failed

 

 

6

Destination Network

 

 

 

Unknown

 

 

7

Destination Host Unknown

 

 

8

Source Host Isolated

 

 

9

Communication with

 

 

 

Destination Network is

 

 

 

Administratively Prohibited

 

 

10

Communication with

 

 

 

Destination Host is

 

 

 

Administratively Prohibited

340