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Method of virtual circuit reconnection without loss of call session
| Details |
Inventors: Whiting, David; Wilbur, Greg; Sultan, Nevein; Mayer, Richard K.;
Assignee: Nortel Networks Limited (St. Laurent, CA)
Primary Examiner: Cangialosi; Salvatore
Assistant Examiner:
Attorney, Agent or Firm: Gibbons, Del Deo, Dolan, Griffinger & Vecchione
In a data communications network in which virtual circuits and encapsulated virtual circuits may be established to carry calls from source terminals to destination terminals through network interfaces, information describing each virtual circuit is returned to, and stored at, the source. Should a virtual circuit or an encapsulated virtual circuit be interrupted, the destination holds the call open while the source requests reestablishment of the virtual circuit or encapsulated virtual circuit, by providing the stored description thereof through an alternate network interface. Upon reestablishment of the virtual circuit or encapsulated virtual circuit, the call proceeds with, or without, loss of data. |
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DETAILED DESCRIPTION In one embodiment, the present invention provides for a method of reestablishing virtual circuits after the interruption thereof.
Specifically, in a communication system comprising a network with a plurality of interconnectable interface ports; a plurality of customer premises equipment (CPE), each selectively connectable to at least one of said interlace ports; a plurality of terminals connected to each of said CPEs and being selectively operable as a source terminal to issue a setup request through its associated CPE for requesting connection to a terminal connected to a different CPE and operable as a destination terminal; wherein each of the interface ports an responsive to a setup request from a source terminal to connect itself via the network to a second interface port and to direct the second interface port to connect to a CPE associated with a requested destination terminal thus forming a virtual circuit between the source terminal and the requested destination terminal; and wherein each CPE is able to determine whether a virtual circuit is interrupted, the invention provides for the following steps to reestablish the virtual circuit after interruption thereof; (i) upon formation of a virtual circuit between a source terminal and a destination terminal, providing information descriptive of the virtual circuit to the source CPE; (ii) storing that virtual circuit information in the source CPE; (iii) upon determining that the virtual circuit is interrupted, establishing a connection between the source CPE and a third interface port; (iv) sending a setup request from the source CPE to the third interface port, which setup request includes the stored virtual circuit information; and (v) establishing a connection in response to the stored virtual circuit information via the network between the third interface port and the second interface port, thereby reestablishing the virtual circuit between the source terminal and the destination terminal.
In a preferred embodiment, when the virtual circuit is interrupted, the second interface port places the virtual circuit in a wait-for-backup mode
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