ICMP error codes

Type 0 Echo Reply 
Type 3 Destination Unreachable 

Code 
0 = net unreachable; 
1 = host unreachable; 
2 = protocol unreachable; 
3 = port unreachable; 
4 = fragmentation needed and DF set; 
5 = source route failed. 

Type 4 Source Quench 
Type 5 Redirect 

Code 
0 = Redirect datagrams for the Network. 
1 = Redirect datagrams for the Host. 
2 = Redirect datagrams for the Type of Service and Network. 
3 = Redirect datagrams for the Type of Service and Host. 

Type 8 Echo 
Type 11 Time Exceeded 
Code 

0 = time to live exceeded in transit; 
1 = fragment reassembly time exceeded. 

Type 12 Parameter Problem 

Code 0 = pointer indicates the error. 
Type 13 Timestamp 
Type 14 Timestamp Reply 
Type 15 Information Request 
Type 16 Information Reply