What is LMI?
LMI is one of those really bad terms that means “Line Management Interface”. Its a bad term for 2 reasons, one because its more of a protocol than an interface, and the second is that one of the two most widely used versions of LMI is referred to as LMI. More about this later. Basically, LMI is a keep-alive mechanism that periodically gives the end user some status information about his connections. Every 10 seconds or so, the end user polls the network, either requesting a dumb sequenced response or channel status information. The network should respond with the requested information; if it doesn’t then the user will consider the connection to be “down” (actually, it takes more than one failure to bring the line down as its possible that a frame was lost due to noise). When the network responds with a “FULL STATUS” response, it includes status information about DLCIs that are allocated to that line. The user can use this information to determine whether its logical connections are abl
