Local area network with an active star topology comprising ring controllers having ring monitor logic function
US5041963A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 29, 1988 |
| Grant date | Aug 20, 1991 |
| Priority date | — |
| Expiry date | Dec 29, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L12/433
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A star local area network includes a ring bus hub (4) capable of being connected to a plurality of nodes (3, 5, 9) geographically distant from the hub by means of low speed serial links (18, 19, 21, 28). The nodes include processor means (2, 30, 31) for creating messages for transfer on the network. A plurality of duplex communication links (18, 19, 21, 28) connect the nodes to the ring bus hub (4). The hub (40) is comprised of a plurality of ring controllers (10, 12, 14, 16) driven by a common clock source (7). Each ring controller is connected by means of a number of parallel lines to other ring controllers in series to form a closed ring. Each one (3) of the plurality of nodes is geographically distant from the hub (4) and is connected to a corresponding one (10) of the ring controllers by means of one (18, 19) of the duplex communication links. The node controllers including node interface means (40) for transmitting the messages as a contiguous stream of words on the duplex communication link. The ring controllers include ring bus interface means (42) for forming the messages into discrete data packets for insertion onto the ring bus and means (32, 34) for bufferring data mess…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.