Local area voice/data communications and switching system

Multiplex communications – Wide area network – Packet switching

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

370 85, H04J 302

Patent

active

047574976

ABSTRACT:
A distributed, digital voice/data communications and switching system for connecting stations which may provide voice-only transmission, data only or voice and data. The system comprises one or more physical nodes, each serving (in an exemplary case) up to about 30 ports (i.e., station interfaces); nodes may be geographically distributed on the user's premises or one or more nodes may be collected together at a common location. The nodes are interconnected via a hierarchical network configuration formed of at least two, generally three, and perhaps even four interlocking networks. The first network is a slotted ring (the "regional" ring) employing coaxial cable to connect the nodes; it carries all control messages transmitted among the nodes, as well as the users' data traffic, using a frame which circulates continuously at about 20 Mbps. The second network is a "star" arrangement carrying PCM-encoded digitized voice traffic; at the hub of the star, in one of the nodes, is a digital voice switch. An optional third network provides a ring-type local area network (the "nodal ring") which connects together a multiplicity of stations at a given node. Each station may include an analog key telephone; further, a personal computer or data terminal may be connected to the phone for transmission purposes. The nodal ring uses frequency division multiplexing to support both analog voice and data transmission over twisted-pair wiring; in the node, the analog voice is digitized and connected to the star network, while digital data is connected to the regional ring for transmission to other nodes. A fourth (so-called "national") ring may be used to interconnect a plurality of regional rings, to allow the system to grow to greater size. Both the hardware and software are modular and may be distributed among the nodes. The software (firmware) comprises a number of processes (or modules) which operate independently of one another and communicate solely by means of messages transmitted over the system's rings and buses internal to the node(s).

REFERENCES:
patent: 4460994 (1984-07-01), Scanlon et al.
patent: 4491838 (1985-01-01), West
patent: 4553234 (1985-11-01), Brandsma et al.
Computer Communications, IPC Science and Technology press, Aug. 1979, pp. 165-176.
Akiyama et al., (International Switching Symposium): Speech-Path Selection and Inter-Processor Signalling in a Load-Shared Distributed Switching System.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Local area voice/data communications and switching system does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Local area voice/data communications and switching system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Local area voice/data communications and switching system will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-668795

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.