Arrangement for minimizing cell-delay variations in a communications system that supports multiple constant-bit-rate connections

A method of limiting transmission-delay variations between transmitted packets bearing segments of communications traffic of individual existing communications-channels that are caused by packets bearing segments of communications traffic of new communications channels in a multi-channel transmission system that is shared by the existing and the new communications channels, comprising:

• determining if packets bearing segments of traffic become available for transmission from a threshold number of the channels at a same time;
• in response to determining that packets bearing segments of traffic do not become available from the threshold number of the channels, allowing a new channel to commence assembling packets bearing segments of traffic to make them available for transmission at said same time;
• and
• in response to determining that packets bearing segments of traffic do become available from the threshold number of the channels, preventing the new channel from commencing to assemble the packets bearing segments of traffic to prevent them from being available for transmission at said same time.

A method of limiting transmission-delay variations between successive asynchronous transfer mode (ATM) cells of traffic of individual channels in a multi-channel ATM system, comprising:

• determining how many cells will mature for transmission in a next cell construction period;
• comparing the determined number of maturing cells against a threshold;
• permitting a channel waiting to begin transmission to commence maturing cells for transmission during said cell construction period, if the number of maturing cells falls below the threshold;
• and
• preventing the waiting channel from commencing to mature cells for transmission during said cell construction period, if the number of maturing cells does not fall below the threshold.

An apparatus for limiting transmission-delay variations between transmitted packets bearing segments of communications traffic of individual existing communications channels that are caused by packets bearing segments of communications traffic of new communications channels in a multi-channel transmission system that is shared by the existing and the new communications channels, comprising:

• means for determining if packets bearing segments of traffic become available for transmission from a threshold number of the channels at a same time;
• means responsive to determining that packets bearing segments of traffic do not become available from the threshold number of the channels, for allowing a new channel to commence assembling packets bearing segments of traffic to make them available for transmission at said same time;
• and
• means responsive to determining that packets bearing segments of traffic do become available from the threshold number of the channels for preventing the new channel from commencing to assemble the packets bearing segments of traffic to prevent them from being available for transmission at said same time.

The apparatus of claim 24 wherein:

• the means for preventing comprises
• means for preventing until such time as it is determined that packets bearing segments of traffic do not become available from the threshold number of the channels at same said such time;
• and
• means for allowing the new channel to commence assembling the packets bearing segments of traffic to make them available for transmission at said same such time.

An apparatus for limiting transmission-delay variations between successive asynchronous transfer mode (ATM) cells of traffic of individual channels in a multi-channel ATM system, comprising:

• means for determining how many cells will mature for transmission in a next cell construction period;
• means for comparing the determined number of maturing cells against a threshold;
• means for permitting a channel waiting to begin transmission to commence maturing cells for transmission during said cell construction period, if the number of maturing cells falls below the threshold;
• and
• means for preventing the waiting channel from commencing to mature cells for transmission during said cell construction period, if the number of maturing cells does not fall below the threshold.