Hybrid units for a communication network
US5491692A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 23, 1993 |
| Grant date | Feb 13, 1996 |
| Priority date | — |
| Expiry date | Dec 23, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L45/04
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A communication network consists of end units (EUs) and distribution units (DUs) coupled together by links which may include local area networks (LANs). The units maintain neighbor tables by sending out Hello messages which indicate the unit type and contain the network service access point (NSAP) IDs or addresses of the units. Data messages (packets) mainly originate and end at EUs. An EU maintains only partial routing information about neighbors, while the DUs collectively maintain complete information about all NSAPs. So if an EU wants to send a packet to an EU which is not a neighbour (and sometimes even if it is), it need merely send it to a neighboring DU; that DU, along with the other DUs, must find a route to the destination EU. This invention provides a hybrid unit (HU), which acts as a DU to EUs but as an EU to DUs. The HU provides DU-like message forwarding but only on a local basis within a subnetwork of EUs and HUs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.