In transparent mode, SPS acts as a transparent router connecting the network segment of the administrators to the segment of the protected servers at the network layer (Layer 3 in the OSI model). All connections must pass through SPS to reach the servers — SPS is a proxy gateway, completely separating the protected servers from the rest of the network. Controlled connections and traffic are inspected on the application level, while other types of connections are simply forwarded on the packet level.
Transparent mode gives users the ability to enter in the IP address of the target/destination server, yet the connection will still be routed through the SPS.
Please see the relevant section of the Administration Guide.