Permitting Traceroute reply

[afshan_nava]

Hi Everyone

can someone pls tell me the difference between the two lines belown in an access-list.

permit icmp any any time-exceeded

and

permit icmp any any ttl-exceeded

Thanks

Afshan

[Sudeep Valengattil]

Here is my understanding;

Type 11 — Time Exceeded

Codes     Description

  0           Time to Live exceeded in Transit

  1           Fragment Reassembly Time Exceeded

If you permit "time-exceeded", it would permit both codes 0 and 1

If you permit "ttl-exceeded", it would permint code 0.

Also check below link

http://www.firewall.cx/networking-topics/protocols/icmp-protocol/156-icmp-time-exceeded.html

[afshan_nava]

Hi Sudeep

Did u find any document from cisco that says so?

Afshan