Answer

The following OID is used for creating the layering relationship for network adapters:

ifStackOID { ".1.3.6.1.2.1.31.1.2.1.3" }

Indexes:

ifStackHigherLayer

ifStackLowerLayer

The MIB-2 OID provides information on a particular relationship between two sub-layers, specifying that one sub-layer runs on top of the other sub-layer. Each sub-layer corresponds to a conceptual row in the ifTable.

The file ic-ifmib-stack.asl is responsible for creating the layering.