On Wed, 13 Nov 2002, Ravindra Jaju wrote:
you mean to say that the application itself started to connect to port 23? ymessenger or libyahoo?
yahoo messenger on windows connected automatically to port 23. ymessenger on linux doesn't, and afaik, none of the other linux clients do either, although almost all are configurable.
Although, at this point i'm inclined to believe that it's a firewall thing - at my end, and that the yahoo clients and servers have a smart workaround.
I'm guessing here, but it seems plausible.
Yahoo has a few servers for Yahoo messenger only. All they have to do, is have ipchains do port forwarding for all ports to port 5050. That way, a client can connect on any port and still work.
Ok, maybe they don't do all ports (I'm not going to do a port scan), but well known ports is a good gamble.
Firewall administrators may block outgoing packets on many ports, but ports like 80, 23, 25, 110 need to be kept open.
The client just needs to cycle through these if 5050 fails - the same way it cycles through host names ({scsa,scsb,scsc}.msg.yahoo.com)
Thoughts.
Philip