GB2276048A - Communications connector system - Google Patents

Abstract

A multiple-wire cable system for networks in which, in a length of multiple-wire cable, a network uses only some of the wires and the cable is provided with an adaptor providing a connection between a second network and the unused wires of the cable. The adaptor may comprise a plug for the cable system 20C and a pair of sockets 20A, 20B each for input to the cable from a network. Connections may be programmed by removable printed circuit boards 20E, 20D. An adaptor may be provided at each end of a cable. <IMAGE>

Description

Communications Connector System The present invention relates to a communications connector system and more particularly to an adaptor for a network such as a star network of computers.

Structured cabling systems for data communications are becoming increasingly popular. They are used for connecting computers, printers, and file servers. Such systems use either shielded or unshielded twisted pair (UTP) cabling, the same wiring as used by telephone systems. UTP cabling can handle the same data rates (up to 100 Mbits per second) as thicker, bulkier cabling, at a fraction of the cost, is more robust, supports a wide variety of protocols and speeds as well as being easier to manage.

Computer devices are usually connected in a star configuration, often with a multi-port repeater (MAU) at the centre of the star. Each computer device connects directly to the MAU, independently of other nodes on the network.

Each cable that connects a device to the MAU is commonly referred to as a branch. The MAU is usually located in a central computer room. Computer devices may be located anywhere within a building. The branches terminate in wall sockets at each location where a computer device is to be connected. The device is then connected to this socket by means of a short cable known as a drop cable.

The star topology can be expanded without disrupting service to other devices on the network. Since each device is isolated, problems at one node do not affect any of the other nodes.

The cable configuration used is related to the particular protocol (e.g. Ethernet, AppleTalk (LocalTalk), ISDN, TokenRing, Arcnet1with which the computer devices on the network operate. Depending on the cable configuration up to 4 wires (2 twisted pairs) are needed. For example, LocalTalk (23Okbs) uses 1 twisted pair and Ethernet (limbs) can use 2 twisted pairs. In addition there are strict requirements on the connectors to be used in conjunction with the respective protocols. For example, Ethernet uses pins 1,2,3,6 of an IEEE specified 8 pin RJ45 connector. LocalTalk, however, uses pins 3,6 of the RJ45 connector. Other protocols use different combinations of the eight wires.

For this reason most structured cabling installations use a run of eight wires per branch to allow flexibility of choice.

Currently, only one device running a single protocol is used per branch of the star network. For example, an IEEE 802.3 Ethernet star network can connect a workstation via a drop cable to an RJ45 wall socket.

In this case only IEEE 802.3 specified Ethernet packets can be used. All devices from interface cards to MAU's running on any of the branches must comply with this requirement. The drop cable, and the cables connecting the wall socket to the MAU patch panel, therefore use only four of the eight wires available. The rest remain unused.

The present invention seeks to provide improved utilisation of existing networks in particular by employing otherwise unused pairs in a star network.

The invention also seeks to provide a system making it possible to run a plurality of star networks on existing structured cabling. The invention further seeks to run networks with a plurality of protocols on one existing structured cabling.

According to a first aspect of the present invention there is provided an adaptor for connecting cables of a multiple-wire cabling system, the cables of which comprise p wires, the adaptor comprising a plug element having p pins and at least two socket elements each having p pins, wherein q pins of the first socket element are connected in accordance with a particular protocol to g respective pins of the plug element, and r pins (where E is up to p minus q) of the second socket element are connected in accordance with the same or a different protocol to r pins of the plug element.

In accordance with a second aspect of the present invention there is provided a system for connecting cables of a branch of a multiple-wire cabling network comprising two or more computers connected via respective cables to the socket elements of a first adaptor in accordance with the present invention, a first socket connecting the first adaptor via a fixed cable to a second socket, a second adaptor in accordance with the present invention connected to the second socket, the socket elements of the second adaptor being connected to respective central computer units.

In accordance with a third aspect of the present invention there is provided a method of connecting cables of a multiple-wire cabling system, the cables of which comprise p wires of which g wires are employed in a first network with a particular protocol, wherein for at least part of the system the data signals of at least two different networks travel along a single piece of cabling, the method comprising the use of adaptors at each end of said length, said adaptors connecting signals from a second network, employing the same or a different protocol, to r unused wires of said length of cable.

It will be appreciated that in the above , and E are integers with g being less than p and r being equal to or less than p minus q.

Preferred embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings of which: Fig.l shows a conventional star network of computers; Fig.2 shows part of a star network in accordance with the present invention; Fig.3 shows enlarged views of an adaptor in accordance with the present invention for use with a wall socket, of which Fig.3a shows a partially-exploded front view, Fig.3b shows a front perspective view and Fig.3c shows a rear perspective view; Fig.4 shows views of an adaptor in accordance with the present invention for use with a socket of a building patch panel, of which Fig.4a shows a partially -exploded bottom view and Fig.4b shows a top perspective view; Fig.5 shows a schematic diagram of the connections within an adaptor according to Fig.3 or Fig.4; Fig.6 is a schematic diagram of a central computer room; Fig.7 shows a modification of the adaptor; and Fig.8 shows a rack for use in a central computer room and which can be used with adaptors as shown in Fig.7.

Referring to the drawings, Fig.l shows a conventional star network 10 of computers 12. Each computer 12 is individually connected to a central unit 14, e.g a multi-port repeater (MAU). The individual connections 16 each comprise eight-wire cabling. Specifically an eight-wire drop cable extending from the computer 12 terminates in an eight pin RJ45 connector which is inserted into a matching RJ45 wall socket. The terminals of this socket are connected via eight-wire cabling fixed in the building to the corresponding terminals of a RJ45 socket on a building patch panel in the central computer room. Here, another eight pin RJ45 connector connects the socket via more eight-wire cabling to the central unit 14.

Fig.2 illustrates two computers 12,13 connected to a single RJ45 wall socket 18 via an adaptor 20 in accordance with the present invention. It is essential that a second adaptor 22 be used at the other end of the fixed building cabling at the corresponding socket of the building patch panel at the other end of the particular structured cabling branch. Fig.3 shows enlarged views of an adaptor 20 and Fig.4 shows views of a corresponding adaptor 22 in the central computing room.

Referring to Fig.3, adaptor 20 comprises a conventional RJ45 plug element 20C, which plugs into the existing wall data socket, and two conventional RJ45 socket elements 20A, 20B for receiving respective drop cables.

The connections between plug element 20C and socket elements 20A, 20B, however, are not conventional. The elements are specially interconnected by plug-in printed circuit units 20D, 20E, so that each wire in use of the two drop cables is connected to a respective pin of the plug element 20C but not both in accordance with the usual protocol.

Referring to Fig.4, adaptor 22 comprises a conventional RJ45 plug element 22C, which plugs into the existing panel data socket, and two conventional RJ45 socket elements 22A and 22B for receiving respective drop cables from the repeater hub interface (MAU) i.e the central unit 14. The connections between plug element 22C and the socket elements 22A and 22B are again not conventional. The elements are specially interconnected by plug-in printed circuit units 22D, 22E which effectively reverse the special connections within adaptor 20. Accordingly the output signals at socket 22A, 22B correspond respectively to the input signals at sockets 20A, 20B.

Fig.5 is an example of an adaptor 20 enabling two Ethernet networks to use a single wall socket 18 (the reverse connections being made at corresponding adaptor 22). Of course the single eight pin plug element 20C has a direct one-to-one mapping of its pins with those of wall socket 18, i.e pins 1 to 8 on the wall socket correspond to pins 1 to 8 of element 20C. On the other hand, the mapping of the pins between plug element 20C and the socket elements 20A, 20B is not one-to-one but is dependent on the network protocol(s) selected.

Connections 23 are those made by printed circuit units 20D and 20E. In this example Socket 20A (pins 1,2,3,6) correspond to plug 20C (pins 1,2,3,6).

Socket 20B (pins 1,2,3,6) correspond to plug 20C (pins 4,5,7,8).

The basic adaptor 20 has only two socket elements 20A, 20B but additional socket elements may be integrated therewith or may be connected to adaptor 20 by means of a plug-in or sliding connection (not shown). With this modification, the adaptor 20 enables one Ethernet network and two LocalTalk networks to use a single wall socket 18. Here: Socket 1 (pins 1,2,3,6) corresponds to plug 20C (pins 1,2,3,6) Socket 2 (pins 2,6) corresponds to plug 20C (pins 4,5) Sockets 3 (pins 2,6) corresponds to plug 20C (pins 7,8) Alternatively the adaptor 20 enables three or four LocalTalk networks to be combined. Here: Socket 1 (pins 2,6) corresponds to plug (pins 2,6) Socket 2 (pins 2,6) corresponds to plug (pins 1,3) Socket 3 (pins 2,6) corresponds to plug (pins 4,5) Socket 4 (pins 2,6) corresponds to plug (pins 7,8) Fig.6 represents a typical central computer room for networks in accordance with the present invention. The room contains a central unit 142 for a first network operating with a first protocol and a central unit 143 for a second network operating with a second protocol.

(Of course the units could operate with the same protocol if desired). The hub patch panel or network interface card 142a of unit 142 has a plurality of connectors 152 corresponding to the maximum number of computers 12 in its network.

In a conventional system each connector 152 in use is connected via a respective drop cable or patch cord 162 to a respective one of an array of RJ45 sockets 122 in a building patch panel 222. In the present system, however, selected connectors 122 are connected in pairs or other pluralities to an adaptor 22 occupying a socket 122 of the panel 222, or a socket 152 of panel 142a or 143a.

The above-described system has a number of advantages.

It permits an extremely efficient use of cabling; whereas previously only a quarter of the wires of a cable might be employed, with the present invention up to 100% of the wires are used. Since upgrading is simply a matter of inserting a pair of adaptors at the ends of a branch, existing systems can easily be modified. Moreover, if desired, repeated changes may be made to cater for changing patterns of use of the rooms of a building and/or new protocols.

Various modifications may be made to the above-described system. The printed circuit units 20D, 20E, 22D, 22E may be replaced by any type of pre-wired circuit. The units may be permanently attached to the rest of the respective adaptor, or they may be replaceable, in which case, for a new network pattern or a new protocol, only these circuit-units need to be interchanged and not the entire adaptor; the latter provides an extremely flexible arrangement.

Any desired combination of the above-mentioned protocols may run in the same sheath as one or more analogue signals. A heterogenous protocol network can run any desired mix of data and/or phone protocols. By modifying a selected number of branches in a star network in these ways, it is possible to create a customised network which provides heterogenous services at one or more selected branches but conventional or standard services at one or more other branches.

The disclosed adaptors comprise two sockets; in a modification they could have three or four sockets. If cables with more than eight wires are used, the number of sockets in a single adaptor may be more than four.

Although reference has been made to plug elements and socket elements, any appropriate two-part coupling elements may be employed.

Fig.7 shows a modified adaptor 322 for use in connection with the rack cabinet 300 of Fig.8. Adaptor 322 comprises four termination sockets 301,302,303,304 for each network branch 310. The branch wires are connected to the back of the adaptor by means of a krone type or other insulation displacement connection.

The rack cabinet, also known as a wiring cabinet or closet, is located on the non-workstation side of the network branches and is used to house a plurality of patch panels 222 so that they are easily accessible, but secure.

Cabinet 300 has a lockable glass door 325 and is connected to building wiring 330.

Each branch may or may not be expanded to offer up to four heterogenous protocol sockets. The adaptor may provide straight mapping in which case a maximum of three termination sockets may be unused.

Up to four termination sockets are possible on any one of the three faces of the adaptor.

The sockets may be positioned at any angle in relation to the vertical.

As with adaptors 20 and 22, adaptor 322 can be reconfigured by user-fitted or factory-fitted printed circuit boards. By including suitable passive and/or active elements, the printed circuits may also serve to maintain and improve the quality of signal transmission by minimising attenuation and cross-talk effects. In particular there may be provided any appropriate combination of: 1. passive and active impedance matching 2. high and low pass noise filters 3. adaptive continuous impedance matching 4. stripline construction 5. multi-layering of circuits 6. voltage protection to shield against internally generated voltage surges 7. shielded and unshielded sockets depending on signalling utility required 8. protocol- or building wiring scheme- specific mapping of eight RJ45 wires on the wall socket to eight wires on the adaptor sockets The individual printed circuit boards may be colour and/or number coded to indicate the protocols it supports per socket and/or the number of wire pairs used per socket.

Each adaptor socket may be terminable using BNC, AUI, RJ45, RJ11, RJ12, Fibre, RS232 and other types of digital and analog connectors. The termination selected for each socket depends on the type of computer service required from each socket. Therefore a mix of connectors types up to a maximum of four is possible for each adaptor.

Any angle may be used between the input and output sides of the connector.

Claims (11)

Claims

1. An adaptor for connecting cables of a multiplewire cabling system, the cables of which comprise p wires, the adaptor comprising a plug element having p pins and at least two socket elements each having p pins, wherein g pins of the first socket element are connected in accordance with a particular protocol to q respective pins of the plug element, and r pins (where r is up to p minus g) of the second socket element are connected in accordance with the same or a different protocol to r pins of the plug element.

2. An adaptor according to claim 1 comprising removable interconnection means for selectively interconnecting the pins of the plug element to the pins of the socket element.

3. An adaptor according to claim 2 wherein the interconnection means is a plug-in printed circuit board.

4. An adaptor substantially as herein described with reference to Fig.3, Fig.4, Fig.5 or Fig.7 of the accompanying drawings.

5. A system for connecting cables of a branch of a multiple-wire cabling network comprising two or more computers connected via respective cables to the socket elements of a first adaptor in accordance with any preceding claim, a first socket connecting the first adaptor via a fixed cable to a second socket, a second adaptor in accordance with any preceding claim connected to the second socket, the socket elements of the second adaptor being connected to respective central computer units.

6. A system according to claim 5 wherein the second socket is part of a patch panel.

7. A system according to claim 6 wherein the patch panel is mounted in a rack cabinet.

8. A system for connecting cables substantially as herein described with reference to the accompanying drawings.

9. A method of connecting cables of a multiple-wire cabling system, the cables of which comprise p wires of which g wires are employed in a first network with a particular protocol, wherein for at least part of the system the data signals of at least two different networks travel along a single piece of cabling, the method comprising the use of adaptors at each end of said length, said adaptors connecting signals from a second network, employing the same or a different protocol, to r unused wires of said length of cable.

10. A method according to claim 9 wherein the protocols are selected from: Ethernet, AppleTalk, LocalTalk, ISDN, TokenRing, ArcnetZ, analogue.

11. A method of connecting cables of a multiple-wire cabling system substantially as herein described with reference to the accompanying drawings.