Currently Requests/Responses are encoded with SSZ and sent across the wire.

SSZ requires a known schema in order to decode the serialized message.

For a message received on the libp2p-RPC stream, one needs to know whether the message is a request or response to decode the message appropriately. Messages could include a prefix bit, specifying which object should be decoded.

Is there a better way to handle this? Should we specify this in the spec?