Proxy VAT-PSTN origination

US6005859A · kind A · utility

Assignee

• Nortel Networks Limited · CA

Inventors

• Joseph C. Harvell · Austin, US
• Gregory T. Stovall · Garland, US

Key dates

• Filing date: Dec 19, 1996
• Grant date: Dec 21, 1999
• Expiry date: Dec 19, 2016

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04M1/2535
• WIPO field: Telecommunications
• WIPO sector: Electrical engineering

Abstract

System and method for extending the use of a VAT telephony application to originate calls into a PSTN as well as a computer network are disclosed. In a preferred embodiment, an adjunct application, referred to as a VAT signaling program ("VSP") running on the same host computer as a conventional VAT-based telephony application prompts a user to enter a destination telephone number and uses the entered number to generate a Q.931 SETUP message, which is encapsulated in a nonstandard, undefined, VAT control message (the "VAT Q.931 message") created to enable additional signaling information to be sent. A signaling interface to the PSTN serving the designated telephone number signals to the VAT application software exactly as if the signaling interface were actually another VAT application software originating a call to the naive VAT application. The signaling interface waits until the user at the computer "answers," and then originates the call into the PSTN network.