Scanning for active ATM virtual channel/virtual path identifiers

Claim 3

The method of claim 1 wherein the communications system operates according to the ATM protocol and the channels are ATM virtual channels (VCs) and the groups of channels are ATM virtual paths (VPs).

Claim 4

The method of claim 1 wherein the fast scan/slow scan combination is performed a plurality of times.

Claim 5

The method of claim 1 wherein the first period of time in the slow scan is more than four times as long as the first period of time in the fast scan.

Claim 6

The method of claim 1 wherein the first period of time in the slow scan is approximately 140 milliseconds and the first period of time in the fast scan is approximately 3.3 milliseconds.

Claim 7

The method of claim 1 wherein the monitoring to identify specific active channels continues on a particular group of channels until a second period of time has passed with no data being communicated on a channel that has not already been noted for that group of channels.

Claim 8

The method of claim 6 wherein the second period of time in the fast scan is approximately 430 milliseconds and the second period of time in the slow scan is approximately 805 milliseconds.

Claim 9

Apparatus for identifying active channels in a communications system in which cells of data being communicated are associated with channels (VCs) and the channels are organized in groups of virtual channels known as virtual paths (VPs), the apparatus comprising: (A) a cell capture system for receiving data being communicated in the communications system and storing information relating to cells received on a specified VP, where the information stored includes identification of the corresponding VC for the cell; (B) means for executing a VP scan in which the cell capture system is successively set to each VP for a VPwait period of time to determine whether there are any active channels within such VP; (C) means for executing a VC scan in which the cell capture system is successively set to each VP that was determined to have an active channel, and the VC identifications stored by the cell capture system reviewed and identified as active channels, where the cell capture for each VP continues for at least a VCwait period of time; (D) means for controlling execution of VP scans and VC scans and for controlling the values of VPwait such that a plurality of VP/VC scan combinations are executed, most combinations being executed with a VPwait that is less that one fourth as long as the VPwait for other VP/VC scan combinations.

Claim 10

Apparatus for identifying active channels in a communications system in which cells of data being communicated are associated with channels (VCs) and the channels are organized in groups of virtual channels known as virtual paths (VPs), the apparatus comprising: (A) a cell capture system for receiving data being communicated in the communications system and storing information relating to cells received on a specified VP, where the information stored includes identification of the corresponding VC for the cell; (B) means for executing a VP scan in which the cell capture system is successively set to each VP for a VPwait period of time to determine whether there are any active channels within such VP; (C) means for executing a VC scan in which the cell capture system is successively set to each VP that was determined to have an active channel, and the VC identifications stored by the cell capture system reviewed and identified as active channels, where the cell capture for each VP continues for at least a VCwait period of time; (D) means for controlling execution of VP scans and VC scans and for controlling the values of VPwait such that a plurality of VP/VC scan combinations are executed, most combinations being executed with a VPwait that is less that one fourth as long as the VPwait for other VP/VC scan combinations.

Claim 11

The apparatus of claim 8 wherein the long VPwait is approximately 140 milliseconds and the short VPwait is approximately 3.3 milliseconds.

Claim 12

The apparatus of claim 8 in which the cell capture system includes: a capture buffer, storage for a channel mask, and buffer control circuitry arranged such that cells associated with channels that are enabled in the mask are "captured", and cells associated with channels that are disabled in the mask are not "captured", where "capture" of a cell means storing data, including at least identification of the cell's associated channel, relating to the cell in the capture buffer; and further comprising: (E) a control system that reviews data in the capture buffer and, for each channel associated with a cell that has been captured, identifies such channel as active and sets the mask to disable such channel.

Claim 13

Apparatus for identifying active channels in a communications system in which cells of data being communicated are associated with channels, the apparatus comprising: (A) a selective cell capture system connected to receive data from the communications system including, a capture buffer, storage for a channel mask, and buffer control circuitry arranged such that cells associated with channels that are enabled in the mask are "captured", and cells associated with channels that are disabled in the mask are not "captured", where "capture" of a cell means storing data, including at least identification of the cell's associated channel, relating to the cell in the capture buffer; and (B) a control system that views data in the capture buffer and, for each channel associated with a cell that has been captured, identifies such channel as active and sets the mask to disable such channel.

Claim 14

Apparatus for identifying active channels in a communications system in which cells of data being communicated are associated with channels, the apparatus comprising: (A) a selective cell capture system connected to receive data from the communications system including, a capture buffer, storage for a channel mask, and buffer control circuitry arranged such that cells associated with channels that are enabled in the mask are "captured", and cells associated with channels that are disabled in the mask are not "captured", where "capture" of a cell means storing data, including at least identification of the cell's associated channel, relating to the cell in the capture buffer; and (B) a control system that views data in the capture buffer and, for each channel associated with a cell that has been captured, identifies such channel as active and sets the mask to disable such channel.