Apparatus and method for discovering a topology for local area networks connected via transparent bridges
US5734824A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 3, 1996 |
| Grant date | Mar 31, 1998 |
| Priority date | — |
| Expiry date | Dec 3, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L45/02
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A system of discovering the active topology of the LANs (local area networks) connected via any apparent bridges that conform to the IEEE 802.1D standard. A discovered active topology of the present invention consists of the active bridges, the LANs and the NMMs (network management modules) that constitute the bridged LAN. The system of the present invention advantageously utilizes the standard (IEEE 802.1D) defined behaviors of transparent bridges to discover the active topology. In so doing, the present invention does not require the bridges to issue any special proprietary frames for development of the active topology. The IEEE 802.1D conforming bridges have the property of forming a path between two conversing end stations. If the two end stations reside in adjacent LANs, the path between these two LANs only has the connecting bridge and no other LAN in between. The present invention utilizes this property in discovering the complete active topology of a bridged LAN via special communications between NMMs located on the LANs. Via cyclic processing and age out functions, the present invention is able to alter the active topology in response to changes within the bridged LAN.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.