Summary

We've now seen a detailed description of two of the IETF MPLS MIBs, indicating how these MIB objects might be manipulated by an NMS in order to create LSPs and tunnels. These MIBs differ in the level of abstraction offered ”the TE MIB provides a useful tunnel metaphor. The LSR MIB requires that up to three tables be manipulated on each agent in the LSP path . These are the in-segment, out-segment, and cross-connect tables respectively, with the addition of the tunnel table on the ingress node. Manipulating just one head-end (or ingress LER) agent can achieve the same result with the TE MIB. The tables used in the latter case consist of a tunnel table, a hop table, and a resource table. The user of an NMS would generally not see the detailed manipulation of these MIB tables. Instead, the NMS would provide a simple interface that offers a limited set of choices, for example, either an LSP or a tunnel as the required connection type. Simplifying such operations is one of the many merits of effective NMS products. The many tables needed for MPLS provisioning underlines the importance of good table insertion discipline. This is particularly so in multiclient provisioning situations. The merit of vendor adoption of standard MIBs is considerable because NEs become easier to manage and to understand.