ICMP

Bit Number


0

1

2

3

4

5

6

7

8

9
1
0
1
1
1
2
1
3
1
4
1
5
1
6
1
7
1
8
1
9
2
0
2
1
2
2
2
3
2
4
2
5
2
6
2
7
2
8
2
9
3
0
3
1
TypeCodeChecksum
Other message-specific information...

Type Name/Codes (Code=0 unless otherwise specified

    
  0Echo Reply
  3Destination Unreachable
    0 Net Unreachable
    1 Host Unreachable
    2 Protocol Unreachable
    3 Port Unreachable
    4 Fragmentation Needed & DF Set
    5 Source Route Failed
    6 Destination Network Unknown
    7 Destination Host Unknown
    8 Source Host Isolated
    9 Network Administratively Prohibited
    10 Host Administratively Prohibited
    11 Network Unreachable for TOS
    12 Host Unreachable for TOS
    13 Communication Administratively Prohibited
  4Source Quench
  5Redirect
    0 Redirect Datagram for the Network
    1 Redirect Datagram for the Host
    2 Redirect Datagram for the TOS & Network
    3 Redirect Datagram for the TOS & Host
  8Echo
  9Router Advertisement
  10Router Selection
  11Time Exceeded
    0 Time to Live exceeded in Transit
    1 Fragment Reassembly Time Exceeded
  12Parameter Problem
    0 Pointer indicates the error
    1 Missing a Required Option
    2 Bad Length
  13Timestamp
  14Timestamp Reply
  15Information Request
  16Information Reply
  17Address Mask Request
  18Address Mask Reply
  30Traceroute