The Peer Group Identifier of the peer group that the given node is to become a member of. If all the bytes of node-peer-group-id are zero AND all the bytes of the node-id are zero, then the value used for the node-peer-group-id is derived from the node-level and node-atm-address. The derived value is that specified in the pnniNodePeerGroupId object of the pnniNodeTable in the ATM Forum PNNI MIB.