American Telephone & Telegraph Co., At&t Bell Laboratories

8631654 Canada Inc.

Robert A Trygar

Alan Eugene Frey

Simon S Ou

John P Ernst

Richard J Basso

John J Driscoll

Gregory S DeWitt

Jon R Diener

Andrew B Struble

Norman R Tiedemann

Carl W Amport

John A Kerkstra

Neenendra R Pandya

David W Kelly

John H Schick

Laurence E Burley

An exemplary method provides access to call origination features contained in an internet protocol multimedia subsystem (IMS) for a subscriber of the IMS who originates a call request from customer premises equipment (CPE) outside of the IMS. The call request is received at a public service identity (PSI) server in the IMS with a phone number to which the call request is routed. An IMS internal desk number is retrieved based on the number of the outside CPE. A first modified call request is transmitted from the PSI server to a telephony application server (TAS) identifying the IMS internal desk number as a request universal resource identity (RURI). Call origination treatment as specified by the subscriber is performed by the TAS. The first modified call request is processed by the TAS to form a second modified call request in which the RURI is a number of a destination party and a P-asserted identity (PAID) is the IMS internal desk number such that the second modified call request appears as if it was initiated from a phone within the IMS. The second modified call request is transmitted to a node in the IMS for further processing and ultimately termination at the destination party.

Extending originating capabilities of a subscriber to devices in any telephony network

Methods and arrangements for associating control messages received in the D-channel of an integrated services digital network (ISDN) line with the call control process to which the message relates are disclosed. With ISDN, a single control channel, called the D-channel, can be used concurrently to control a plurality of calls. As each call is initiated, a call control process and data structure including the unique identity of the call, are created. The data structures associated with the same D-channel are linked together. When a control message including a given identity is received, the data structures associated with the D-channel conveying the message are searched in sequence until a data structure having the given identity is found. The contents of this data structure are used to access the control process associated therewith. When the search reveals no matching identity and the message is a call setup message, a new process and data structure are created.

Switching system control arrangements

Growing community of inventors

Winfield, IL, United States of America

Robert A Trygar