COMSPHERE 6800 Series Nework Management System1-34 August 1994 6800-A2-GB21-102. Use the worksheets provided in the user’s manual that came with the 740/741 ACCULINKmultiplexer to determine how much overhead bandwidth is needed for each channel. Addeach channel’s data rate with its overhead bandwidth to determine the total bandwidthrequired for each channel.Add the bandwidth requirements for all the channels (no bandwidth will actually beallocated until the connection is made). This total figure represents the channel group’scapacity. You may want to include extra bandwidth to accommodate future networkgrowth. To determine the available bandwidth, execute either the Time Slot Summary (tss)command or the Channel Group Summary (cgs) command.NOTEKeep these worksheets as a record of channel bandwidthrequirements and the actual bandwidth allocated to each channelgroup. You may need to refer to them during future reconfiguration.3. Execute the Create Channel Group (crcg) command to create the channel group. Set theappropriate configuration parameters and routing specifications as described later in thissection.4. As part of the Create Channel Group (crcg) command, determine if a channel group shouldbe routed only over routes that meet attribute requirements. (For example, you couldspecify that channel group abc can only traverse paths that satisfy the user1 attribute.When automatic routing is used, the channel group abc will only be connected over a pathwhere user1 is available on each hop. A fixed route definition will only be accepted if itmeets the attribute user1 criteria.) See the Attribute Routing Requirements section forfurther details.5. Allocate bandwidth to the channel group by executing the Make Channel GroupConnection (mkcgc) command. If a route is available, the channel group will be connected.Channel Group RoutingNOTENot applicable to serial synchronous channel groups.The ACCULINK multiplexers allow for three channel group routing choices: first, second, andthird choices. When a channel group connection is made, the multiplexers attempt to route thechannel group according to the first choice route. If this attempt fails, the second is tried and thenthe third choice. This routing scheme also occurs automatically if a channel group connection isbroken due to a facility failure.The automatic and fixed options are as follows.automatic routeConfigured so that the channel group is routed automatically by the multiplexersthemselves, using the nodes’ routing tables.
