This attribute displays the Local Management Interface user side
procedure event history in order of occurrence. An event is
represented by a single symbol. A '+' symbol indicates a good
event. An 'X' symbol indicates a protocol error event. The left most
event is the most recent to occur. The provisioned eventCount (nN3/
N393) dictates the maximum number of events displayed. A good
event is triggered by receipt of a valid status message. An error
event is either a nT1/T391 timer expiry or receipt of a status
message with bad sequence numbers.