Patent ID: 7352758

Claim:
In a communication system, apparatus for changing the bandwidth of a circuit switched connection without taking down the connection comprising: a network management system arranged to issue a connection create request effective during a first time period and a connection modify command effective during a second time period; a first switching circuit comprising a first interface and a second interface, the first switching circuit being arranged to receive data at the first interface, be responsive to the connection create request during the first time period to reserve first resources at a first bandwidth for transmitting the data between the first and second interfaces at the first bandwidth and to launch a first path setup message using a signaling protocol, be responsive to the modify command during the second time period to reserve virtually concatenated second resources at a second bandwidth greater than the first bandwidth for transmitting the data between the first and second interfaces at the second bandwidth and to launch a second path setup message using the signaling protocol, be responsive to a first path acknowledge message during the first time period to complete a first connection between first and second interfaces using the first resources, and be responsive to a second path acknowledge message during the second time period to complete a second connection between first and second interfaces using the second resources, the first and the second connections being combined as a virtually concatenated connection; a second switching circuit comprising a third interface and a fourth interface, the second switching circuit being arranged to receive the data at the third interface, be responsive to the first path setup message during the first time period to reserve third resources at the first bandwidth for transmitting the data between the third and fourth interfaces at the first bandwidth and to launch the first path acknowledge message using the signaling protocol, and be responsive to the second path setup message during the second time period to reserve virtually concatenated fourth resources at the second bandwidth for transmitting the data between the first and second interfaces at the second bandwidth and to launch the second path acknowledge message using the signaling protocol; and at least one network coupling the network management system, first switching circuit and second switching circuit.