protobuf (with any implementation) is not an RPC stack; This is a sterilization stack. However, you can use WCF to provide RPC, but hook protobuf-net as a serialization layer inside WCF . What to do?
I have a custom RPC layer using http, but I havenβt implemented it for TCP, and I havenβt looked at callbacks. WCF provides these built-in functions, so maybe it's worth a look?