Multiplex communications – Wide area network – Packet switching
Patent
1990-06-22
1993-03-09
Olms, Douglas W.
Multiplex communications
Wide area network
Packet switching
370 61, 370 851, H04L 1256
Patent
active
051930900
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
This invention relates to access protection and priority control in environments required to have distributed queuing access control. The processes to be described that embody the invention are applicable to a large number of environments. These environments have the common elements of high speed digital data transfer in packets along a digital data bus communications medium between a plurality of contending stations distributed linearly along that bus medium.
BACKGROUND OF THE INVENTION
The comprises invention alone and in combination the setting and control of data packet buffer thresholds as delimited in one or more counters within a station, and includes limits to the rate of request to send data packets and limits to the total number of packets issued by a station. In brief, counters and limits (thresholds) on counters, and queues and limits (thresholds) on queues, are used to control transmission (for example, transmission rate) processes on the bus communications medium.
Another environment in which this invention may be applied is the interaction between the Central Processing Unit (CPU) of a computer and the Peripheral Interface Adaptor (PIA) and/or any other component attached which are required to contend for access on to a high speed computer bus architecture utilising any length or speed digital data packet transfer communications medium.
The invention is also applicable to a wide variety of other digital data transfer environments allowing for partial or full implementation of the mechanism, since partial and full application of the mechanism provides different advantages, problem elimination and economies of operation for each of the applicable environments.
SUMMARY OF THE INVENTION
In order to describe the invention a preferred environment and physical application architecture will now be described, however, it will be understood by those skilled in this particular field and those in other related fields that the preferred embodiment is purely a means of one implementation of the invention.
This invention in its partial or full implementation is applicable in one embodiment to the proposed Institute of Electrical and Electronic Engineers (I.E.E.E.) Standard 802.6 Distributed Queue Dual Bus (DQDB) Metropolitan Area Network (MAN) Draft D.O. of Jun. 24, 1988 and, provides hitherto unknown advantages and advances to the implementation proposed therein.
I.E.E.E. 802.6 Draft Standard is a combined Medium Access Control (MAC) and Physical Layer application. These layers are respectively layers 2 and 1 of the Open Systems Interconnect (OSI) Seven Layer Reference Model.
It is important to appreciate that the invention is applicable to all seven layers of this Model apart from many other data transfer environments. I.E.E.E. 802.6 utilises a Dual Bus Queued Packet and Synchronous Switch (QPSX) which is a distributed switch
etwork that will fulfill the requirements of a public MAN. The Switch architecture of QPSX is based around two contra-directional buses, FIG. 1. These two buses involve a dual loop of transfer medium (nominally optical fibre but not necessarily so) arranged as a logical bus. One unit serving as master and the bus configuration thus eliminating the need to remove data from the medium as is done in ring configurations.
Writing to the bus is done only in "empty" slots/packets/cells so that an OR function suffices to combine the one bits `1` of the data with the totally all `0` slot packet on the bus. This simplifies the circuitry of each station which is in series with the bus traffic. The fact that the loop always has an opening provides a very important fault tolerance.
The use of dual buses and a plurality of contending input/output data sources called stations, also called nodes, has created the need for a distributed queuing protocol. A process called scheduling used, in this the prior art, which comprises the sending of reservations "up stream" when a station wants to transmit "down stream". Each station keeps an up/down counter running continuously
REFERENCES:
patent: 3680056 (1972-07-01), Kropfl
patent: 4021653 (1977-05-01), Sharp et al.
patent: 4354248 (1982-10-01), Conger et al.
patent: 4445116 (1984-04-01), Grow
patent: 4460806 (1984-07-01), Canniff et al.
patent: 4500989 (1985-02-01), Dahod
patent: 4510601 (1985-04-01), Delpit et al.
patent: 4536874 (1985-08-01), Stoffel et al.
patent: 4542502 (1985-09-01), Levinson et al.
patent: 4566097 (1986-01-01), Bederman
patent: 4604755 (1986-08-01), Murray
patent: 4614909 (1986-09-01), Jarvfalt
patent: 4689760 (1987-08-01), Lee et al.
patent: 4771391 (1988-09-01), Blasbalg
patent: 4782523 (1988-11-01), Galand et al.
patent: 4815071 (1989-03-01), Shimizu
patent: 4853958 (1989-08-01), Rabipour
patent: 4953157 (1990-08-01), Franklin et al.
Bell Communications Research, "Dual-Tone Multifrequency Receiver Generic Requirements for End-to-End Signaling Over Tandem-Switched Voice Links", TR-TSY-000181, Issue 1, Mar., 1987.
Bell Communications Research, "Customer Line Signaling", Section 6.2, TR-TSY-000064 LSSGR, Dec., 1984.
Bell System, "Bell System Pub. Switched Tel. Srvc. Interconnection Criteria for Domestic Pub. Land Mobile Radio Srvc, Domestic Pub. Cellular Telecommunications Srvc. & Maritime Radio Srvc.", Bell System Tech. Ref., No. 326-1987, Dec., 1981.
Bell System Tech. Ref., "Description of the Analog Voiceband Interface Between the Bell System Local Exchange Lines & Terminal Equipment", No. 326-125, Jan., 1983.
Engineering Dept., "EIA Standard, Telephone Instruments with Loop Signaling for Voice Band Applications", Electronic Industries Association, Issue 1, RS-470, Jan., 1981.
Engr. Dept., "EIA Standard, Private Branch Exchange (PBX) Switching Equip. for Voice-Band Applications", Electronic Industries Association, RS-464, Dec., 1979.
Hartung et al., "Dual-Tone Multifrequency Receiver Using the WE DSP32 Digital Signal Processor", American Telephone & Telegraph Application Note.
Oppenheim et al., Digital Signal Processing, Prentice-Hall, Inc., pp. 287-289 (1975).
Mock, "Add DTMF Generation and Decoding to DSP-uP Designs: Digital Signal Processing Applications with the TMS320 Family", vol. 1, Texas Instruments, pp. 545-557 (1989).
Microelectronics Analog Communications Handbook, Mitel Corporation, pp. 3-27 to 3-33 (1990).
Boston Technology Voice Processing Systems, "B. Technical Specification", ACCESS.TM. Series Technical Manual, pp. B-1 to B-18.
"DSC-2000 VoiceServer.TM.: The Fast Track to Digital Voice Processing" (Brochure from Digital Sound Corporation, Carpinteria, Calif.).
Berry Leslie T.
Filipiak Janusz
Gordon James
Olms Douglas W.
Samuel T.
LandOfFree
Access protection and priority control in distributed queueing does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Access protection and priority control in distributed queueing, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Access protection and priority control in distributed queueing will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-214652