ICMP Types TYPE CODE Description Echo Reply Network Unreachable Host Unreachable Protocol Unreachable Port Unreachable Fragmentation needed but no frag.. bit set Source routing failed De
Trang 1ICMP Types TYPE CODE Description
Echo Reply Network Unreachable Host Unreachable Protocol Unreachable Port Unreachable Fragmentation needed but no frag bit set Source routing failed
Destination network unknown Destination host unknown Source host isolated (obsolete) Destination network administratively prohibited Destination host administratively prohibited Network unreachable for TOS
Host unreachable for TOS Communication administratively prohibited by filtering Host precedence violation
Precedence cutoff in effect Source quench
Redirect for network Redirect for host
Query Error x
Trang 2ICMP Types TYPE CODE Description
10
II
11
12
12
13
14
15
16
17
18
2 Redirect for TOS and network
Redirect for TOS and host Echo request
Router advertisement Route solicitation TTL equals 0 during transit TTL equals 0 during reassembly
IP header bad (catchall error) Required options missing Timestamp request (obsolete) Timestamp reply (obsolete) Information request (obsolete) Information reply (obsolete) Address mask request Address mask reply
Query Error
xX
xX
xX
xX
X
xX
xX
xX
xX
xX xX