Cisco ATM Vcl Entry

1.3.6.1.2.1.37.1.7.1

An entry in the VCL table. This entry is used to model a bi-directional VCL. To create a VCL at an ATM interface, either of the following procedures are used: Negotiated VCL establishment (1) The management application creates a VCL entry in the atmVclTable by setting atmVclRowStatus to createAndWait(5). This may fail for the following reasons: - The selected VPI/VCI values are unavailable, - The selected VPI/VCI values are in use. Otherwise, the agent creates a row and reserves the VPI/VCI values on that port. (2) The manager selects an existing row(s) in the atmTrafficDescrParamTable, thereby, selecting a set of self-consistent ATM traffic parameters and the service category for receive and transmit directions of the VCL. (2a) If no suitable row(s) in the atmTrafficDescrParamTable exists, the manager must create a new row(s) in that table. (2b) The manager characterizes the VCL's traffic parameters through setting the atmVclReceiveTrafficDescrIndex and the atmVclTransmitTrafficDescrIndex values in the VCL table, which point to the rows containing desired ATM traffic parameter values in the atmTrafficDescrParamTable. The agent will check the availability of resources and may refuse the request. If the transmit and receive service categories are inconsistent, the agent should refuse the request. (3) The manager activates the VCL by setting the the atmVclRowStatus to active(1) (for requirements on this activation see the description of atmVclRowStatus). If this set is successful, the agent has reserved the resources to satisfy the requested traffic parameter values and the service category for that VCL. (4) If the VCL terminates a VCC in the ATM host or switch, the manager turns on the atmVclAdminStatus to up(1) to turn the VCL traffic flow on. Otherwise, the atmVcCrossConnectTable must be used to cross-connect the VCL to another VCL(s) in an ATM switch or network. One-Shot VCL Establishment A VCL may also be established in one step by a set-request with all necessary VCL parameter values and atmVclRowStatus set to createAndGo(4). In contrast to the negotiated VCL establishment which allows for detailed error checking (i.e., set errors are explicitly linked to particular resource acquisition failures), the one-shot VCL establishment performs the setup on one operation but does not have the advantage of step-wise error checking. VCL Retirement A VCL is released by setting atmVclRowStatus to destroy(6), and the agent may release all associated resources.