Patent ID: 7940718

Claim:
A method of operating a first radio base station in a mobile communication system comprising the first radio base station and a trace log storage node, wherein the first radio base station is responsible for information exchanged with one or more user equipments, wherein the method of operating the first radio base station causes trace log information to be supplied to the trace log storage node, the method comprising: becoming responsible for serving a user equipment session; beginning a trace process of the user equipment session; when a session report criterion has been satisfied, sending a trace status indication to or alternatively receiving the trace status indication from a second radio base station in the mobile communication system, the trace status indication including an indicator of a session report cause and a time of satisfying the session report criterion; using the indicator of the session report cause and the time of satisfying the session report criterion to identify a set of trace log information stored in a record buffer; and if the set of trace log information is not empty, then supplying the set of trace log information to the trace log storage node.