When the TCP transport is configured for LAN communication (with the NDDS_Transport_Property_t::classid property), the IP address is the LAN address of the peer and the port is the server port used by the transport (the NDDS_Transport_TCPv4_Property_t::server_bind_port property).
When the TCP transport is configured for WAN communication (with the NDDS_Transport_Property_t::classid property), the IP address is the WAN or public address of the peer and the port is the public port that is used to forward traffic to the server port in the TCP transport.