Local area network packet protocol for combined voice and data transmission
US4581735A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 1983 |
| Grant date | Apr 8, 1986 |
| Priority date | — |
| Expiry date | May 31, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L12/64
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
In order to control the transfer of packets of information among a plurality of stations, the instant communications system, station and protocol contemplate first and second oppositely directed signal paths. At least two stations are coupled to both the first and the second signal paths. A station reads one signal from a path and writes another signal on the path. The one signal is read by an arrangement which electrically precedes the arrangement for writing the other signal. Packets are transmitted in a regular, cyclic sequence. A head station on a forward path writes a start cycle code for enabling each station to transmit one or more packets. If a station has a packet to transmit, it can read the bus field of a packet on the forward path. Responsive thereto, a logical interpretation may be made as to whether the forward path is busy or is not busy. If the path is not busy, the packet may be written on the path by overwriting any signal thereon including the busy field. If the path is busy, the station may defer the writing until the path is detected as not busy. In order to accommodate different types of traffic, the head station may write different start cycle codes. For exam…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.