The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 02, 1989
Filed:
Jun. 15, 1987
Andrew H Arrowood, Raleigh, NC (US);
Alan E Baratz, Chappaqua, NY (US);
Philip F Chimento, Jr, Durham, NC (US);
John E Drake, Jr, Pittsboro, NC (US);
John L Eisenbies, Raleigh, NC (US);
James P Gray, Chapel Hill, NC (US);
Karla J Norsworthy, Raleigh, NC (US);
Diane P Pozefsky, Chapel Hill, NC (US);
International Business Machines Corporation, Armonk, NY (US);
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.