Method and apparatus for enhancing the operating capabilities of a telephone switching system

US4782519A · kind A · utility

Assignee

• NETWORK ACCESS ASSOCIATES LIMITED · US

Inventors

• Rajendra Patel · Lake Zurich, US
• Kenneth A. Lauffenburger · Dallas, US
• David Thorn · London, GB
• Donald D. Binford, Jr. · Round Rock, US
• Zye K. Cheng · Richardson, US
• Yeong-Haw Yang · Plano, US
• Gerald K. Coley · Terrell, US
• Charles Clifton Miller, III · Lathrop, US

Key dates

• Filing date: May 22, 1986
• Grant date: Nov 1, 1988
• Expiry date: May 22, 2006

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04Q3/42
• WIPO field: Telecommunications
• WIPO sector: Electrical engineering

Abstract

A method and apparatus is described for providing extended subscriber features, e.g., equal access, to otherwise non-conforming central offices of a telephone switching system. According to the invention, a register module is interposed between the subscriber line and an input of the central office for intercepting digits from the subscriber line intended for the central office and for receiving subscriber information from the central office identifying the subscriber line. The register module includes a memory having a plurality of address locations and a control circuit for analyzing the intercepted digits to determine whether processing of the subscriber call requires an extended subscriber feature. If so, the intercepted digits are processed to generate a coded signal, the coded signal including the address location where the stored digits and the subscriber information resides in the memory. The coded signal is then used by the marker in the central office to select an appropriate outgoing trunk to complete the subscriber call. An associated trunk module interposed between the switch element of the central office and the outgoing trunks receives the coded signal and in respons…