Token ring spanning tree protocol
US6304575A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 31, 1998 |
| Grant date | Oct 16, 2001 |
| Priority date | — |
| Expiry date | Aug 31, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L49/25
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
An improved spanning tree protocol for use by token ring intermediate devices having one or more Concentrator Relay Function (CRF) entities and associated Bridge Relay Function (BRF) entities. Each CRF and BRF entity preferably includes a spanning tree engine and corresponding database for individually executing an instance of the spanning tree algorithm and is configured to select a different Bridge Protocol Data Unit (BPDU) message type for use in executing its respective spanning tree algorithm. The selection of BPDU message type by the CRF and BRF spanning tree engines preferably depends on the routing configuration of the associated CRF. The selection of BPDU message type by the CRF entities assures that they are dropped by legacy intermediate devices and only acted upon by the originating CRF or another CRF coupled thereto. The selection of BPDU message type by the BRF entities assures that they are passed through CRF entities unmodified and yet are acted upon by other BRF entities and/or any legacy intermediate devices coupled to the associated BRF entity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.