Using a TCP Tunnel for Duplex WCF connections through Proxies in enterprise scenarios

We're using a duplex contract for one feature in our yet to be released enterprise level LOB application that utilizes a thick client built with WPF and a server built with WCF.

During development so far we've been using the net.tcp binding for best performance. Now that d开发者_运维百科eployment is coming up and issues such as internet access through a web proxy come to light, net.tcp isn't suitable anymore.

I've started using wsHttp and wsDualHttp but have realised in the meantime that duplex connections through a web proxy (and with NAT traversal) isn't really possible.

Now I'm thinking: why can't I set up a tcp tunnel (using proprietry software that supports web proxies, using HTTP CONNECT) and get the best of both worlds, proxy support, speed and security?

It would seem this is a common requirement.

Your options are not expansive. Microsoft's Service Bus is probably your best bet, if it works for your needs. The other options are:

• VPN: Pretty self-explanatory.
• SSH: SSH has tunneling functionality built-in. If you only have a small number of connections, you might be able to use an off-the-shelf SSH client and server, but with a larger number of connections it's hard to ensure that they all stay connected reliably. Several companies make SSH components you might be able to build upon (they didn't work for our needs), but they are more oriented toward the remote-execution use of SSH than tunneling.
• A DIY TCP tunnel, which is a big job. Not impossible, but a big job. And will require a tremendous amount of testing to make sure you've got it right.

As far as running WCF over a tunneled connection, if you go that route, you won't have any problems. All the bindings and features work-- callbacks, reliability, message security, transport security, transactions, all work just fine.