AIS AI2524 Example Virtual Circuit Ranges, Because the X.25 protocol requires the DTE and DCE to

AI2524 Router Card User’s Manual

used to prevent one side from monopolizing the virtual circuits, and is useful for X.25 interfaces with a small total number of SVCs available.

Six X.25 parameters define the upper and lower limit of each of th three SVC ranges. A PVC must be assigned a number less than the numbers assigned to the SVC ranges. An SVC range is not allowed to overlap another range.

Note:	Because the X.25 protocol requires the DTE and DCE to
	have identical virtual circuit ranges, changes you make to
	the virtual circuit range limits when the interface is up are
	held until the X.25 protocol restarts the packet service.

To configure X.25 virtual circuit ranges, complete these tasks as ap- propriate for your configuration:

1.Set the lowest incoming-only circuit number (default is 0).

x25 lic circuit-number

2.Set the highest incoming-only circuit number (default is 0).

x25 hic circuit-number

3.Set the lowest two-way circuit number (default is 1).

x25 ltc circuit-number

4.Set the highest two-way circuit number (default is1024 for X.25 and 4095 for CMNS).

x25 htc circuit-number

5.Set the lowest outgoing-only circuit number (default is 0). x25 loc circuit-number

6.Set the highest outgoing-only circuit number (default is 0). x25 hoc circuit-number

Each of these parameters can range from 1 to 4095, inclusive. The val- ues for these parameters must be the same on both ends of an X.25 link. For connection to a PDN, these values must be set to the values assigned by the network. Virtual circuit 0 is not available except for marking unused ranges (by setting the lower and upper limits to 0).

Example: Virtual Circuit Ranges

This example sets the virtual circuit ranges of 5 to 20 for incoming calls only (from the DCE to the DTE) and 25 to 1024 for either incom- ing or outgoing calls. It also specifies no virtual circuits for outgoing calls (from the DTE to the DCE). Up to 4 permanent virtual circuits can be defined on virtual circuits 1 through 4.

Page 12-4	August 1997
	2524UM