Local Management Interface (LMI) is a signaling standard used between routers and frame relay switches. Communication takes place between a router and the first frame relay switch it's connected to. Information about keepalives, global addressing, IP Multicast and the status of virtual circuits is commonly exchanged using LMI.
There are three standards for LMI: ANSI's T1.617 Annex D standard; ITU-T's Q.933 Annex A standard; and the "Gang of Four" standard, named for the four companies that developed it: Cisco, DEC, StrataCom and NorTel (Northern Telecom).
The "Gang of Four" LMI standard uses DLCI 1023[1]. The T1.617 Annex D and Q.933 Annex A standards use DLCI 0[1].