Method and apparatus for performing link defragmentation subject to an interface rate constraint

An apparatus for use in defragmenting at least one time division multiplexed link in a communication system comprising a network having a plurality of nodes, wherein provisioned circuits corresponding to traffic demands are assigned to particular time slots of the link, the apparatus comprising:

• a processor;
• and
• a memory coupled to the processor;
• wherein the processor is operative to perform the steps of:
• computing an optimum layout of free space for the link subject to at least an interface rate constraint;
• selecting particular free slots from the optimum layout of free space;
• determining a hitless migration sequence for one or more of the circuits to one or more of the selected free slots;
• and
• adjusting the time slot assignments of said one or more circuits in accordance with the determined migration sequence in order to defragment the link.

An article of manufacture comprising a computer-readable medium storing one or more programs for use in defragmenting at least one time division multiplexed link in a communication system, wherein provisioned circuits corresponding to traffic demands are assigned to particular time slots of the link, the one or more programs when executed in a processor performing the steps of:

• computing an optimum layout of free space for the link subject to at least an interface rate constraint;
• selecting particular free slots from the optimum layout of free space;
• determining a hitless migration sequence for one or more of the circuits to one or more of the selected free slots;
• and
• adjusting the time slot assignments of said one or more circuits in accordance with the determined migration sequence in order to defragment the link.