With a server-side Interceptor deployment, once a TCP handshake has been completed between the server-side...

Destination NAT is performed on the Interceptor, changing the destination IP adress from the client IP to the SteelHead's IP.

The server sees the IP address of the SteelHeads in-path interface as its client, so there is no need for the Interceptor to forward it.

They are GRE-encapsulated by the Interceptor, and forwarded using the SteelHead IP.

The Interceptor tunnels them over the connection using port 7850 to the SteelHeads.

The Interceptor applies the MAC address of the SteelHead's in-path interface and forwards at layer 2.