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Wireshark-dev: Re: [Wireshark-dev] ports

From: Jaap Keuter <jaap.keuter@xxxxxxxxx>
Date: Tue, 26 Aug 2008 06:43:25 +0200
Hi,

1. Disable the dissector you, as user, do not want.
2. Make strong heuristic determination of correct protocol and modify dissectors accordingly.

Note that two protocols running at the same server port is actually a design fault. Every node in the network can present services which can be accessed through a set port. Historically the ports 1-1024 are considered "well known ports", which means that it is very common to have certain services on certain ports. This was later extended beyond 1024, see the services file which lists many more services on many more ports. It's a kind of services directory. Still this doesn't stop multiple services to be provided on the same port on different nodes. Nothing Wireshark can do about that other than trying to make educated (automatic/user guided) guesses.

Thanx,
Jaap

Martin Corraine (mcorrain) wrote:
Hello,
Two of my dissectors that I wrote use the same tcp port, the ged125 (being reviewed) and a proprietary protocol). Their default port is both 5000. When I have the default ports the same the ged125 fails to dissect but the other one still functions. How do I overcome this issue? Thanks,
martin