Multiplex communications – Wide area network – Packet switching
Patent
1988-10-06
1991-02-12
Olms, Douglas W.
Multiplex communications
Wide area network
Packet switching
370 54, H04J 326
Patent
active
049930184
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to an N.times.N (where N is a natural number, same below) or N.times.M self-routing switching system having N number of incoming lines and N or M number of outgoing lines which is optimal for use for high-speed packet switching or asynchronous transfer mode switching.
In telephone switching (line switching), once speech path is set up, the speech path is maintained until the conversation of the call is finished. In the case of multiplex transmission, calls (channels) are switched at a high speed, but the positions of the calls on the frame remain the same, so simple sequential switching is sufficient. As opposed to this, with packet switching, each of the packets has its own destination The destinations of the packets as seen by a time series are diverse, so the above two methods cannot be used. Therefore, a method is adopted of placing a packet into a memory once and then distributing the same to outgoing lines (memory switching). However, this memory switching requires time, so it is not suitable in cases where high-speed switching is required.
A self-routing speech path is suitable for cases of high-speed switching to different outgoing lines for each packet or each cell (asynchronous transfer mode blocks), such as high-speed packet switching or asynchronous transfer mode switching, and for cases where centralized control of the speech path by software is not desired because of the need for high speed call processing.
PRIOR ART
A so-called Banyan-type self-routing speech path has already been proposed in, for example, 1986 INTERNATIONAL ZURICH SEMINAR ON DIGITAL COMMUNICATIONS D4.1, pp. 135-139 "EXPERIMENTS IN WIDEBAND PACKET TECHNOLOGY" R. W. Muise et al.
FIG. 1 is a circuit diagram showing a Banyan-type self-routing speech path as an example of the prior art. This is comprised of 2.times.2 unit self-routing switches S.sub.ij (where ij is 11, 12, . . .) by reverse shuffle wiring as shown in the illustration (in this example, an 8.times.8 Banyan is shown). Each packet of the incoming line side is given control information showing the outgoing lines (in this example, binary-notation outgoing line number). Using the control information, each switch is operated and the transmission information (INF) sent to the designated outgoing line. For example, when the control information is "010" and the packet is input to IN of the S.sub.11, the first stage (i=1) switch sends the packet to its own "0" output since the MSB of the control information is "0". Receiving this, S.sub.21 views the next bit of the MSB and since this is "1", sends it to the "1" output. Receiving this, S.sub.32 views the LSB and since this is "0" sends it to the "0" output. In this way, the packet is sent to the target outgoing line 010.
FIG. 2 is a view showing the construction in the case of expanding the scale of the speech path of FIG. 1. In the above-mentioned Banyan-type self-routing speech path, to increase the number of incoming and . outgoing lines, for example, to make a 16.times.16 Banyan, the construction of FIG. 2 is adopted. That is, two 4.times.4 Banyans are arranged, four 2-unit switches are arranged at the outgoing side, and wiring performed as illustrated to construct an 8.times.8 Banyan. Similarly, two 8.times.8 Banyans are arranged eight 2.times.2 unit switches are arranged at the outgoing side, and wiring performed as illustrated to construct a 16.times.16 Banyan. A 32.times.32 Banyan etc. can be similarly constructed. In general, any N.times.N Banyan can transmit information to a targeted outgoing line by log2 N stage cascade connection of 2.times.2 unit switches. Note that in a unit switch, the outgoing terminal is given twice the operating speed of the incoming terminal to avoid congestion.
As mentioned above, a Banyan type self-routing speech path is constructed based on the principle of dichotomization, so expansion of scale is achieved by combining two N.times.N switches and N number of 2.times.2 switches to make a 2N.times.2N switch. The increases are in units of m
REFERENCES:
patent: 4022982 (1977-05-01), Hemdal
patent: 4173713 (1979-11-01), Giesken et al.
patent: 4392221 (1983-07-01), Hesketh
patent: 4550397 (1985-10-01), Turner et a.
patent: 4630259 (1986-12-01), Larson et al.
patent: 4651318 (1987-03-01), Luderer
patent: 4731878 (1988-03-01), Vaidya
patent: 4811333 (1989-03-01), Rees
The 6th Annual Symposium on Computer Architecture, Apr. 23-25, 1979, IEEE, (New York, U.S.), T.-Y. Feng et al.: "A Microprocessor Controlled Asynchronous Circuit Switching Network".
IEEE Journal on Selected Areas in Communications, vol. SAC-4, No. 8, Nov. 1986, IEEE, (New York, U.S.), J. S. Turner: "Design of an Integrated Services Packet Network".
International Journal of Electronics, vol. 56, No. 6, Jun. 1984, (Basingstoke, Hampshire, GB), S. K. Paranjpe et al.: "A New Concept for Supermodular Alignment Network".
IEEE Transactions on Computer, vol. C-34, No. 2, Feb. 1985, IEEE, (New York, U.S.), M. Kumar et al.: "Switching Strategies in Shuffle-Exchange Packet-Switched Networks".
Journal of the Institution of Electronic and Radio Engineers, vol. 56, No. 6/7, Jun./Jul. 1986, IERE, (London, GB), M. Nagasawa et al.: "Packet Switching Network Access Protocols for Multi-Media Packet Communications".
Proceedings of the 1981 International Conference on Parallel Processing, Aug. 25-28, 1981, IEEE, (New York, U.S.), R. J. McMillen et al.: "Performance and Implementation of 4.times.4 Switching nodes in an Interconnection Network for PASM".
Abe Shunji
Fukui Toshimasa
Hajikano Kazuo
Hayami Hichiro
Isono Osamu
Fujitsu Limited
Jung Min
Olms Douglas W.
LandOfFree
Self-routing switching system with multiple link connections bet does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Self-routing switching system with multiple link connections bet, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Self-routing switching system with multiple link connections bet will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-25639