Help to Identify Pattern and suggest Name

I have to create a WCF service which will reside between set of web apps and web service on either side.

This WCF service will forward calls from it's clients to other systems acting as gateway while maintaining status of each request forwarded and response received from downstream systems. It may receive responses for few requests it forwarded at later time. In that case it will relay back those updates to upstream systems. State of each request it received will be maintained and can be queried by upstream systems occasionally.

What is this SOA pattern called? How should I name the WCF service? Is it gateway or an agent or queue?