GB1350800A - Data transmission - Google Patents
Data transmissionInfo
- Publication number
- GB1350800A GB1350800A GB4668071A GB4668071A GB1350800A GB 1350800 A GB1350800 A GB 1350800A GB 4668071 A GB4668071 A GB 4668071A GB 4668071 A GB4668071 A GB 4668071A GB 1350800 A GB1350800 A GB 1350800A
- Authority
- GB
- United Kingdom
- Prior art keywords
- stations
- loop
- loops
- station
- circuits
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/46—Interconnection of networks
- H04L12/4637—Interconnected ring systems
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Small-Scale Networks (AREA)
- Time-Division Multiplex Systems (AREA)
- Communication Control (AREA)
- Data Exchanges In Wide-Area Networks (AREA)
Abstract
1350800 Digital transmission; closed loop systems WESTERN ELECTRIC CO Inc 7 Oct 1971 [8 Oct 1970 (2)] 46680/71 Heading H4P A digital transmission system has a plurality of closed loops each including a number of stations B entering message blocks thereon, and a plurality of switching stations C for selectively transferring messages in accordance with the address between adjacent loops. Loops are normally closed by an A station which selectively repeats transmissions and preferably prevents continuous recycling. Loops need not be synchronous but it is preferable that the A stations provide timing and that this should be by way of a carrier wave. Due to buffering at the C stations adjacent loops need not be precisely synchronized. Error control may be incorporated, but supervision may be provided, for example, over a telephone network. A trunk loop i.e. 10 not incorporating access facilities may connect subsidiary loops. By-pass i.e. alternative transmission paths may be provided either to divert traffic from heavily laden or faulty sections and some loops may be duplicated. Message blocks may include reserved bit positions and each station includes a shift register in series with a loop for serially accepting and entering data from and to the loop with parallel data access means also detection means to prevent insertion in "loop busy conditions". "Hog" circuits may also be incorporated to prevent stations having continuous access to the detriment of other stations having messages for transmission. A station B may comprise a demodulator and amplifier (52) Fig. 3 (not shown) together with a clock pulse recovery and synchronizing circuit (53) for the generator (55). Demodulator output is received by a shift register (54), see also Fig. 5 (not shown) which is a serial input serial output nine stage register having parallel access to all stages which are made available to control circuits (56) which detects the sync. code, block control word also destination code, see Figs. 7-10 (not shown), the output controlling in turn write and read circuits (59, 62) which operate in conjunction with overflow eight stage register 58 having parallel reading and writing access. Thus single message blocks may be received by register 58 or entered through 65 which may insert guard bits also interchange source and destination codes to return undelivered messages to a sender. B stations may be modified for A station use by providing, for example, a master timing generator, eliminating read and write circuits (62, 59) but a circuit (66) see Fig. 14 (not shown) must be provided to initialize the loop when block framing is lost which may be accomplished by inserting nine zeros followed by a series of 1's. C stations may comprise two B stations (600, 601) Fig. 15 (not shown) each coupled into one loop, which deliver into and receive from stores (603, 604) all controlled at (605). A B station, e.g. (600) may retransmit messages on the same loop, e.g. (1) or in response to "foreign" addresses may be transferred to the other B station for insertion on to loop (2). To prevent message blocks being lost, the size of stores is made large enough relative to anticipated amount of interloop traffic. Stations (600, 601) need not operate at the same repetition rate nor be in synchronism. Store units (603, 604) may each comprise a magnetic core matrix with associated X, Y selection circuits in accordance with address information from appropriate decoders (615, 616) Fig. 16 (not shown). Detailed arrangements for performing various operations are described in the Specification.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US7918570A | 1970-10-08 | 1970-10-08 | |
US7908070A | 1970-10-08 | 1970-10-08 |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1350800A true GB1350800A (en) | 1974-04-24 |
Family
ID=26761597
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB4668071A Expired GB1350800A (en) | 1970-10-08 | 1971-10-07 | Data transmission |
Country Status (9)
Country | Link |
---|---|
JP (1) | JPS5422042B1 (en) |
AU (1) | AU461110B2 (en) |
BE (1) | BE773555A (en) |
DE (1) | DE2151016C3 (en) |
ES (1) | ES396125A1 (en) |
FR (1) | FR2111124A5 (en) |
GB (1) | GB1350800A (en) |
IT (1) | IT939960B (en) |
NL (1) | NL177876C (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0006325A1 (en) * | 1978-06-05 | 1980-01-09 | Fmc Corporation | Data transmission system for interconnecting a plurality of data processing terminals |
GB2138651A (en) * | 1983-04-21 | 1984-10-24 | Standard Telephones Cables Ltd | Local Area Networks Comprised of Interconnected Sub Networks |
US4486852A (en) * | 1978-06-05 | 1984-12-04 | Fmc Corporation | Synchronous time-shared data bus system |
GB2170079A (en) * | 1984-12-14 | 1986-07-23 | Vitalink Communications Corp | Method and apparatus for bridging local area networks |
US4627070A (en) * | 1981-09-16 | 1986-12-02 | Fmc Corporation | Asynchronous data bus system |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3810100A (en) * | 1971-12-16 | 1974-05-07 | Collins Radio Co | Looped direct switching system |
DE2659533C2 (en) * | 1976-12-30 | 1984-04-26 | ANT Nachrichtentechnik GmbH, 7150 Backnang | Method for the transmission of messages in a telecommunications system with a large number of subscriber stations |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NO123200B (en) * | 1967-11-23 | 1971-10-11 | Svenska Handelsbanken |
-
1971
- 1971-10-06 NL NL7113719A patent/NL177876C/en not_active IP Right Cessation
- 1971-10-06 AU AU34269/71A patent/AU461110B2/en not_active Expired
- 1971-10-06 BE BE773555A patent/BE773555A/en not_active IP Right Cessation
- 1971-10-07 ES ES396125A patent/ES396125A1/en not_active Expired
- 1971-10-07 IT IT7029871A patent/IT939960B/en active
- 1971-10-07 FR FR7136163A patent/FR2111124A5/fr not_active Expired
- 1971-10-07 GB GB4668071A patent/GB1350800A/en not_active Expired
- 1971-10-08 JP JP7878771A patent/JPS5422042B1/ja active Pending
- 1971-10-08 DE DE19712151016 patent/DE2151016C3/en not_active Expired
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0006325A1 (en) * | 1978-06-05 | 1980-01-09 | Fmc Corporation | Data transmission system for interconnecting a plurality of data processing terminals |
US4486852A (en) * | 1978-06-05 | 1984-12-04 | Fmc Corporation | Synchronous time-shared data bus system |
US4627070A (en) * | 1981-09-16 | 1986-12-02 | Fmc Corporation | Asynchronous data bus system |
GB2138651A (en) * | 1983-04-21 | 1984-10-24 | Standard Telephones Cables Ltd | Local Area Networks Comprised of Interconnected Sub Networks |
GB2170079A (en) * | 1984-12-14 | 1986-07-23 | Vitalink Communications Corp | Method and apparatus for bridging local area networks |
Also Published As
Publication number | Publication date |
---|---|
FR2111124A5 (en) | 1972-06-02 |
IT939960B (en) | 1973-02-10 |
AU3426971A (en) | 1973-04-12 |
AU461110B2 (en) | 1975-05-15 |
DE2151016C3 (en) | 1981-09-24 |
NL177876C (en) | 1985-12-02 |
DE2151016A1 (en) | 1972-04-13 |
NL177876B (en) | 1985-07-01 |
JPS5422042B1 (en) | 1979-08-03 |
DE2151016B2 (en) | 1980-12-04 |
BE773555A (en) | 1972-01-31 |
ES396125A1 (en) | 1974-04-16 |
NL7113719A (en) | 1972-04-11 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4218756A (en) | Control circuit for modifying contents of packet switch random access memory | |
US3680056A (en) | Use equalization on closed loop message block transmission systems | |
SU1321383A3 (en) | Digital switching device | |
EP0335848B1 (en) | Packet data switch for transferring data packets from one or a plurality of incoming data links to one or a plurality of outgoing data links | |
CA1161546A (en) | Videotex system provided with protection means against transmission errors | |
JPS60219891A (en) | Digital exchange system | |
US4076964A (en) | Time division system for synchronizing functions controlled by different clocks | |
GB1108003A (en) | Signal switching system | |
JPH0685510B2 (en) | Digital transmission system | |
WO1986005054A1 (en) | Arrangement for accessing and testing telecommunication circuits | |
US3742144A (en) | Interconnected loop digital transmission system | |
US3609244A (en) | Conditional replenishment video system with variable length address code | |
US4355387A (en) | Resynchronizing circuit for time division multiplex system | |
GB1372797A (en) | Communication apparatus | |
CA1317660C (en) | Circuit element - cross-point between two bus lines | |
GB1350800A (en) | Data transmission | |
US4387466A (en) | Half-duplex digital transmission system | |
GB1296181A (en) | ||
JPS58205347A (en) | Information reforming device | |
US3281527A (en) | Data transmission | |
GB1336542A (en) | System for tranferring information | |
GB1499010A (en) | Transmission of digital information signals together with a preceding address signal | |
JPS582497B2 (en) | Signal speed compensator | |
US3753241A (en) | Shift register having internal buffer | |
JPH0143499B2 (en) |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed | ||
PCNP | Patent ceased through non-payment of renewal fee |