Abstract: A system and method for recording accounting times by an Agent in a network and retrieving the accounting times by the network Manager. Three types of data objects in each of the Agent's stored records are provided. Record Number is the sequence number of the record in the file. Recording time is an indication of the time the record was stored in the file since a certain point in time, such as after the Agent's clock began running. Record Type is the particular type of record stored. The Record Type can either be DATA representing normal accounting data or TIME representing time data used for correlating the Manager's and the Agent's time-keeping. Upon receipt of an accounting data record of type DATA, the manager uses the record's Recording time to help determine the point of time accorded to that event. The Manager then uses the previous record of type TIME to adjust the Recording time of the received accounting data record relative to the Manager's precise calendar time.

Abstract: In a communications network, each network node can maintain its own list of network resources in a topology database. When the state of a resource "owned" by a particular node changes, that node broadcasts a topology database update (TDU) message to adjacent nodes. Each adjacent node updates its own topology database and rebroadcasts the message. To minimize the amount of information that must be included in TDU messages when two nodes are reconnected after an outage, each node assigns flow reduction sequence numbers (FRSNs) to TDU meassages and keeps a record of the FRSN for the last TDU message sent to an adjacent node. The node also records, for each resource in its database, the FRSN of the last TDU message including that resource. When two nodes are reconnected, the sending node includes in the TDU message only those resources having a FRSN greater than the FRSN assigned to the last TDU sent to the adjacent node to which the TDU message is directed.

Abstract: Each network node in a communications network maintains its own copy of the network topology database defining network resources. Each resource record contains a "timer" field which is initially set to a maximum value but which may be decremented on a daily basis. If the timer field is decremented to zero without being reset, the node unilaterally removes the resource record from its copy of the database. The timer field will normally reach zero only for obsolete resource records since each network node responsible for a resource broadcasts a timer-resetting message for the resource (1) each time the resource status changes, (2) when the node first joins or rejoins the network, and (3) on a periodic (weekly) basis regardless of whether conditions (1) or (2) have occurred.