Description: This object is applicable only for the bidirectional tunnel that has the forward and reverse LSPs in the same tunnel or in the different tunnels.

This object holds the same value as that of the mplsTunnelIndex of mplsTunnelEntry if the forward and reverse LSPs are in the same tunnel. Otherwise, this object holds the value of the other direction associated LSP's mplsTunnelIndex from a different tunnel.

The values of this object and the mplsTunnelExtDestTnlLspIndex object together can be used to identify an opposite direction LSP i.e. if the mplsTunnelIndex and mplsTunnelInstance hold the value for forward LSP, this object and mplsTunnelExtDestTnlLspIndex can be used to retrieve the reverse direction LSP and vice versa.

This object and mplsTunnelExtDestTnlLspIndex values provide the first two indices of tunnel entry and the remaining indices can be derived as follows, if both the forward and reverse LSPs are present in the same tunnel, the opposite direction LSP's Ingress and Egress Identifier will be same for both the LSPs, else the Ingress and Egress Identifiers should be swapped in order to index the other direction tunnel.