Abstract: A gateway includes a plurality of gateway modules, coupled together for servicing communication among all of the ports coupled to any of the modules. The number of ports serviced may be increased by adding a gateway module with a minimum of physical and operational configuration changes to the existing gateway modules of the gateway. A gateway module is particularly suitable for use in a scalable gateway. The gateway module includes: a plurality of network ports, a commissioned communication engine, a reserve communication engine, a switchover circuit, and a scaling circuit. In one implementation protocol conversion by the gateway module facilitates voice over Internet (VOIP) communication including network ports coupled to T1/E1 interfaces of plain old telephone systems (POTS) switched telephone networks.