This object is the VPI of the bi-directional control direct connection between a specific LEC and the LES, the dedicated circuit carrying control signaling (as opposed to broadcast control traffic) between just that one client and the server. An admin cares because it lets them locate the exact ATM VC carrying control messages for one client's connection when troubleshooting that client specifically, rather than the whole ELAN's control distribute circuit. For example, tracing why one particular client isn't receiving LE_ARP responses would start by finding its control connection using this VPI and the matching VCI.