[Techtalk] Bypassing ICMP Packet Blockage

[Maria Blackmore]

On Sat, 28 Dec 2002, Silvio Manuel wrote:

> Situation description: dial-up connection to the Interent, 
> local ISP, ICMP blockage
> 
> Symptoms: Unable to ping, trace or do anything needing ICMP packets 

but you can connect to things out on the internet?

> Ways I've gone through: nothing special just tried to start tracing
> from 2nd or 3rd or so hop, which was in vain, heard about tracing
> tools that do tracing from behind proxies (don't know if it works for
> this case)
> 
> Question: Is there anyway to bypass this blockage or are there any
> applications tracing without using ICMP packets? (I guess not!)

Actually, unix traceroute traditionally uses UDP for the outbound packets,
and listens for inbound ICMP packets resulting from the packets it sends
out.

you could try tcptraceroute
(http://michael.toren.net/code/tcptraceroute/) which may or may not get
you somewhere, but if inbound ICMP is being blocked you really need to
complain loudly at the company that supplies your internet connection, it
really is incredibly bad practise.

good luck

Maria