Method and apparatus for bandwidth management in a digital loop carrier system

A digital loop carrier system, comprising:

• transport cards connectable by a communications medium;
• a plurality of service cards, a subset of which are connected to a transport card having a given bandwidth capacity, each of the service cards supporting at least a plurality of channels;
• and
• a bandwidth manager comprising:
• means for allocating a first initiated call to a given time slot of a transport card;
• means for assigning the given time slot a given default bandwidth;
• means for determining whether the call is voice or data while the first call is in progress;
• and
• means for selectively reducing the given default bandwidth allocated to the first call if the first call is voice and if necessary to ensure that a second call initiated, while the first call remains in progress, can be assigned the given default bandwidth.

A bandwidth manager for use in a digital loop carrier system, the system comprising a plurality of service cards connectable to at least one transport card having a given bandwidth capacity, each of the service cards supporting at least a plurality of channels, comprising:

• means for allocating a first initiated call to a given time slot of the at least one transport card;
• means for assigning the given time slot a given default bandwidth;
• means for determining whether the call is voice or data while the first call is in progress;
• and
• means for selectively reducing the given default bandwidth allocated to the first call if the first call is voice and if necessary to ensure that a second call, initiated while the first call remains in progress, can be assigned the given default bandwidth.

A terminal for use in a digital loop carrier system, comprising:

• a transport card having a given bandwidth capacity connectable to a communications medium;
• a service card connected to a transport card, the service card supporting a plurality of subscriber channels;
• and
• a bandwidth manager comprising:
• means for allocating a first initiated call to a given time slot of a service card;
• means for assigning the given time slot a given default bandwidth;
• means for determining whether the call is voice or data while the first call is in progress;
• and
• means for selectively reducing the given default bandwidth allocated to the first call if the first call is voice and if necessary to ensure that a second call initiated while the first call remains in progress, can be assigned the given default bandwidth.

A method for managing bandwidth in a digital loop carrier system, the system comprising a remote digital terminal connected to a plurality of subscriber lines and a central digital terminal connected to a central office of a telecommunications network, said remote digital terminal and said central digital terminal each including at least one service card having a plurality of channels, at least one transport card and circuitry for transferring signals therebetween, said at least one transport card of said remote digital terminal being connected to said at least one transport card of said central digital terminal by a medium having a given bandwidth capacity, the method comprising the steps of:

• upon initiation of a first call through one of said subscriber lines, allocating the first call to a time slot of the at least one transport card of said remote digital terminal, said time slot having a given default bandwidth;
• while the first call is in progress, determining whether the call comprises a given compressible signal;
• and
• if the first call comprises said given compressible signal, selectively reducing the default bandwidth allocated to the first call if necessary to ensure that if a second call is initiated while the first call remains in progress, said second call can be assigned the given default bandwidth.