US Patent 7289522 Shared dedicated access line (DAL) gateway routing discrimination

An approach for providing telephony services over a data network is disclosed. A communication system includes a gateway that receives a signal to establish a call with a called station from a calling station in a telephone network (such as a Class 3 network) associated with one of a plurality of customers. The gateway generates a message according to a prescribed application layer protocol to establish the call with the called station over the data network. The message includes an alias host address identifying the one customer. The system also includes a server that receives the message from the gateway and to route the call to the called station based upon the alias host address.