Multiplex communications – Wide area network – Packet switching
Patent
1982-03-15
1985-05-07
Olms, Douglas W.
Multiplex communications
Wide area network
Packet switching
370 94, H04J 302, H04J 600
Patent
active
045162395
ABSTRACT:
A variation on a carrier sense multiple access/collision detection (CSMA/CD) system protocol for local area, packet, random access, broadcast networks is disclosed for effectively servicing both voice and data traffic. When the instant method is used, a mix of periodic voice traffic and aperiodic data traffic can be transmitted on a channel without the voice packets colliding. Also, an upper bound on the delay experienced by the periodic traffic can be established. In the instant method, aperiodic sources contend for a channel as in conventional CSMA/CD networks. However, unlike conventional protocols, periodic sources transmit a preempt field, responsive to which aperiodic sources terminate transmission. Also unlike conventional protocols, a periodic "time slot" may be delayed up to one packet transmission time when the network is busy transmitting aperiodic data. Additional information can be transmitted in an overflow field so that a receiver can supply periodic samples at regular intervals with the advantageous result of obviating discontinuities in a reconstructed analog speech waveform. Also unlike conventional CSMA/CD networks, the system capacity can be fully utilized by periodic sources. Still further, the instant method contemplates a system with no centralized control to assign "time slots" or to reallocate capacity between periodic and aperiodic sources. In addition, movable time slots allow timing discrepancies between periodic sources to be tolerated.
REFERENCES:
patent: 3851104 (1974-11-01), Willard et al.
patent: 4063220 (1977-12-01), Metcalfe et al.
patent: 4199661 (1980-04-01), White et al.
patent: 4259663 (1981-03-01), Gable
patent: 4271507 (1981-06-01), Gable et al.
patent: 4281380 (1981-07-01), DeMesa et al.
patent: 4292623 (1981-09-01), Eswaran et al.
patent: 4332027 (1982-05-01), Malcolm et al.
patent: 4337465 (1982-07-01), Spracklen et al.
patent: 4347498 (1982-08-01), Lee et al.
8th Conference on Local Computer Networks, IEEE 1983; "Some Characteristics of Movable Slot TDM"; Maxemchuk; pp. 62-69.
National Telecommunications Conference, Nov. 29-Dec. 3, 1981, Mehmet Yanilmaz et al.: "A Technique for Voice-Data Integration Over Packet Radio Channels", pp. G4.1.1-G4.1.5.
National Telecommunications Conference, Nov. 30-Dec. 4, 1980, Ichiro Iida et al.: "Random Access Packet Switched Local Computer Network with Priority Function", 37.4.1-37.4.5.
Digest of Papers Spring Compcon. 82, Feb. 22-25, 1982, Tobagi et al.: "The EXPRESS-NET, A Local Area Communication Network Integrating Voice and Data", pp. 121-127.
Bell System Technical Journal, vol. 61, No. 7, Sep. 82; Maxemchuk: "A Variation on CSMA/CD Yields Moveable TDM Slots in Integrated Voice/Data Local Network", pp. 1527-1550.
AT&T Bell Laboratories
Olms Douglas W.
Roddy Richard J.
Scutch III Frank M.
LandOfFree
System, apparatus and method for controlling a multiple access d does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with System, apparatus and method for controlling a multiple access d, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and System, apparatus and method for controlling a multiple access d will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1803811