What does cause Socket not getting response?

[Sky Loi]

I have Socket connection to 3rd party server to handle the request and response. These days, we found Socket read timeout exception when the socket waiting for response. The request I sent out has no problem. What will cause Socket not getting response? I have the following thinking: 3rd party server does not send response at all.

Is there any other case?
1. Firewall block the response somehow?
2. Response message is lost some where?
etc

Thanks for your idea in advance.

[luri ron]

do a traceroute to see if there is any packet drop in your network route.
if not, it is the application related.

[Ryan Beckett]

If you can connect through HTTP, then try using the port 5678 for the Socket.