We have SPDY to SPDY and HTTP to SPDY proxy functionality implemented in Jetty for a while now.

An important and very common use case however is a SPDY to HTTP proxy. Imagine a network architecture where network components like firewalls need to inspect application layer contents. If those network components are not SPDY aware and able to read the binary protocol you need to terminate SPDY before passing the traffic through those components. Same counts for other network components like loadbalancers, etc.
Another common use case is that you might not be able to migrate your legacy application from an HTTP connector to SPDY. Maybe because you can’t use Jetty for your application or your application is not written in Java.

Quite a while ago, we’ve implemented a SPDY to HTTP proxy functionality in Jetty. We just didn’t blog about it yet. Using that proxy it’s possible to gain all the SPDY benefits where they really count…on the slow internet with high latency, while terminating SPDY on the frontend and talking plain HTTP to your backend components.

Here’s the documentation to setup a SPDY to HTTP proxy:

Jetty SPDY to HTTP Proxy