How Ice client connect to the Internet through proxy server?

Ice doesn't work over HTTP. The client must be able to create an outgoing connection over your firewall. It's fine if the firewall is doing network address translation and port translation, but it doesn't work if the firewall restricts clients to HTTP only.

This is an age-old topic, that has been discussed in the CORBA community for many years. If a firewall restricts traffic to HTTP only, then this means there is a policy in place that only HTTP is allowed. Technlogies like SOAP try to trick such firewalls into believing that a remote request would actually be HTTP traffic. To me, that's simply "hacking the firewall", because the sole purpose of this exercise is to create clients that pretend to do HTTP traffic, when in reality they are doing remote procedure invocations. This, on othe other hand, is a clear violation of the firewall's "HTTP only" policy, i.e., if a firewall only allows HTTP, then only HTTP should be used. If not, then there is no reason for the firewall to restrict traffic to HTTP only.

Regarding socks: Socks is transparent, so if you firewall allows outgoing connections using socks, then all you would have to do is to compile Ice with the socks library. We didn't test this yet ourselves, but off hand, I don't see a reason why this wouldn't work.

Have a look at this article:

http://www.socks.permeo.com/TechnicalResources/DevelopDocuments/SOCKSifyingClientAp0CE5/index.asp

Note that I didn't try this with Ice myself yet. However, in principle I don't see a reason why Ice wouldn't work with socks.