CN2433783Y

CN2433783Y - Distributed processing type digital loop carrier equipment local terminal machine

Info

Publication number: CN2433783Y
Application number: CN 00226518
Authority: CN
Inventors: 邱燕炜
Original assignee: Xian Jiaotong University
Current assignee: Xian Jiaotong University
Priority date: 2000-06-16
Filing date: 2000-06-16
Publication date: 2001-06-06
Anticipated expiration: 2010-06-16

Abstract

The utility model discloses a distributed processing type digital loop carrier equipment local terminal machine. The utility model comprises a main treatment board, a cross connecting board, a digital relay board, etc. The main treatment board, the cross connecting board, the digital relay board, etc. are connected through TDM interfaces and high speed serial ports, wherein, the TDM interfaces are used for transporting data streams and embedded message streams, high speed serial ports are used exclusively for transporting various message streams between single boards, an HDLC which can extract or insert message streams directly on the relay E1 interface message path is arranged on the digital relay board, the HDLC is responsible for carrying the base layer treatment to message streams, and the main treatment board is responsible for the management of the equipment and the high layer treatment of the message streams.

Description

Distribution process formula digital loop carrier equipment central office terminal

The utility model relates to communication equipment, is the part of user access networks equipment, specifically a kind of central office terminal of digital loop carrier equipment.

Digital loop carrier DLC equipment is the access network equipment between service node and the subscriber terminal equipment, it is made up of central office terminal, remote termination and optical line terminal three parts, be mainly used in the telecommunication service of supporting the following speed of 2Mbit/s, as: plain old telephone service POTS, integrated services digital network ISDN business, Digital Data Net DDN business etc.

The central office terminal of existing digital loop carrier equipment generally all adopts processing mode in the message set, promptly all are sent on the veneer that contains big capacity advanced data link controller HDLC pond from the message of service node with from the message of remote termination and focus on, the advantage of this mode is a Message Processing efficient height, the cost of average every subscribers feeder is low when being applied to witched-capacity network, to be that the difficulty of equipment is all relative with risk concentrate on the veneer that this piece contains high-capacity H DLC pond shortcoming, and the utilance in HDLC pond is low when being applied to the low capacity network, the cost height of average every subscribers feeder.

The purpose of this utility model is to overcome the existing shortcoming of processing mode in the above-mentioned employing message set, a kind of digital loop carrier equipment central office terminal that adopts the message distribution processing mode is provided, the capacity of its advanced data link controller HDLC is level and smooth increasing with the increase of network capacity, the utilance height of HDLC when being applied to the low capacity network, the cost of average every subscribers feeder is relatively stable.

The utility model comprises Main Processing Unit, interconnection plate and Digital Trunk Board etc., link to each other with the high speed serial ports by the time division multiplexing tdm interface between them, wherein the time division multiplexing tdm interface is used for transmitting data stream and embedded message stream, and the high speed serial ports is exclusively used in the various message flows between the transmission veneer.Dispose the advanced data link controller HDLC that can on relaying E1 interface message passage, directly extract or insert message flow on the Digital Trunk Board, it is responsible for message stream is carried out bottom layer treatment, and by carrying out the message transmission between TDM interface or high speed serial ports and the Main Processing Unit.Main Processing Unit is responsible for the high level of the management of equipment and message flow and is handled, as the processing of standard V5.2 interface the 3rd layer protocol etc.The interconnection plate is used for data flow and embedded message stream are carried out time gas exchange, makes data on arbitrary passage or message can be delivered to any other passage and gets on.Main Processing Unit and the some common distributed treatment that realize message flow of Digital Trunk Board, wherein the quantity of Digital Trunk Board depends on the quantity and the capacity of institute's band distal end node.

Below in conjunction with drawings and Examples the utility model is elaborated:

Fig. 1 is a theory diagram of the present utility model.

Fig. 2 is the theory diagram of the utility model Digital Trunk Board.

Fig. 3 is the electrical schematic diagram of the utility model Digital Trunk Board.

Fig. 4 is the annexation figure that adopts full point-to-point structure between each veneer of the utility model.

Fig. 5 is the annexation figure that adopts National Federation of Trade Unions's line structure between each veneer of the utility model.

Referring to Fig. 1, Main Processing Unit 1, interconnection plate 2 and Digital Trunk Board 3 all provide time division multiplexing tdm interface 4 and high speed serial ports 5, wherein TDM interface 4 links to each other in point-to-point mode, be used for transmitting data stream and embedded message stream, high speed serial ports 5 links to each other in the mode of bus, be exclusively used in the various message flows of transmission between veneer, as the webmaster message between V5.2 interface C-channel message and veneer etc.3 pairs of message streams of Main Processing Unit 1 and Digital Trunk Board carry out distributed treatment, and interconnection plate 2 carries out time gas exchange between each TDM interface 4, make data on arbitrary passage or message can be delivered to any other passage and get on.

Referring to Fig. 2, Digital Trunk Board 3 is made up of No. four relaying E1 interface circuits 7, little switching matrix 8, No. eight advanced data link controller HDLC circuit 9 and central processing unit 10, provides three road TDM interfaces 4, one tunnel high speed serial ports 5 and four road E1 interfaces 6.The capacity of little switching matrix 8 is 256 * 256, can realize clog-free time gas exchange between the TDM of eight 2M speed bus.In eight TDM buses that little switching matrix 8 links to each other, four are used to connect 7, three of E1 interface circuits and are used to provide 4, one TDM interfaces to be used to connect HDLC circuit 9.Eight road HDLC circuit 9 are shared a TDM bus, they can be that each

road E1 interface

6 and 4 TDM interfaces are shared flexibly by little switching matrix 8, such as, be first via E1 interface assignment three road HDLC, be the second road E1 interface assignment two-way HDLC, be that the third and fourth road E1 interface respectively distributes one road HDLC, also have one road HDLC to distribute to TDM interface 4.The HDLC circuit 9 of distributing to E1 interface 6 is used for directly extracting on E1 interface message passage or inserting message flow, and the HDLC circuit 9 of distributing to TDM interface 4 is used for carrying out point-to-point communication with Main Processing Unit 1, to transmit the message flow of big flow.Central processing unit 10 is used for carrying out bottom layer treatment from the message of HDLC circuit 9 and high speed serial ports 5, and E1 interface circuit 7, little switching matrix 8 and HDLC circuit 9 are controlled.

Referring to Fig. 3, four road E1 interface circuits 7 are realized that by chip N1～N8 little switching matrix 8 is realized that by chip N13 eight road HDLC circuit 9 are realized by chip N9～N12.Central processing unit adopts the MCS51 single-chip microcomputer N15 of 40M dominant frequency, is equipped with 32K external data memory N14.The chip N17 that resets is used to guarantee the reliable reset of single-chip microcomputer N15, and right+5V supply voltage monitors that when brownout, the single-chip microcomputer N15 that promptly resets destroys normal data to prevent single-chip microcomputer N15 irregular operating.High speed serial ports 5 is connected on the serial ports of single-chip microcomputer N15 after open-collector gate chip N18 buffering, and its baud rate can reach 1.25Mbit/s.The reason that adopts open-collector gate N18 is to link to each other with bus mode in order to make between the serial ports 5.Programmable logic array N16 is used to coding-decoding circuit of realizing address and sequential etc., so that other each chip is organically connected together.Clock signal clk and frame synchronizing signal FS provide the synchronous timing signal of TDM bus to chip N5～N13 by programmable logic array N16.

When actual networking is used, part E1 interface 6 links to each other with switch, another part E1 interface 6 links to each other with each remote termination of digital loop carrier equipment, and the effect of central office terminal is exactly to carry out the processing of message flow between switch and each machine far away and realize channel allocation to data flow according to result.Its workflow is such: flow through from the embedded message of E1 interface 6 and deliver to central processing unit 10 after HDLC circuit 9 extracts and carry out bottom layer treatment such as format conversion etc., by high speed serial ports 5 or TDM interface 4 transmission of messages is carried out high-risely handling as the processing of V5.2 interface the 3rd layer protocol etc. to Main Processing Unit 1 then, message after the processing is transmitted back to the central processing unit 10 of a certain Digital Trunk Board 3 again by high speed serial ports 5 or

TDM interface

4,10 pairs of message of central processing unit are inserted in the message channel of E1 interface 6 by HDLC circuit 9 after remaking necessary bottom layer treatment.As seen, the processing of message flow is distributed in Main Processing Unit 1 and the Digital Trunk Board 3 and finishes.

Message transmission between Main Processing Unit 1 and the Digital Trunk Board 3 has two paths to walk, and one through high speed serial ports 5, and another is through TDM interface 4.Generally speaking, protocol message is walked TDM interface 4, and webmaster message is walked high speed serial ports 5.When wherein a paths damages, all message all can be walked from another paths, promptly can play the effect of mutual backup between two paths.Because the main application of TDM interface 4 is transmitting data streams, rather than message flow, so under the enough situation of the handling capacity of high speed serial ports 5, message is preferably all walked high speed serial ports 5, and do not walk TDM interface 4, help reducing the complexity of the hardware cost and the software of Main Processing Unit 1 like this.

The method that message is walked TDM interface 4 is certain passage that takies in its 31 data passages, transmits in the mode of HDLC.Because message is as being embedded in the data flow under this mode, so be called embedded message stream, it requires the receiving-transmitting sides of message all to dispose the HDLC circuit.Focus on the digital loop carrier equipment central office terminal of mode for existing employing, from the embedded message of E1 interface 6 by TDM interface 4 transparent transmission to Main Processing Unit 1, rather than on the central processing unit 10 of Digital Trunk Board 3, carry out bottom layer treatment earlier, Digital Trunk Board 3 does not just need to dispose HDLC circuit 9,0 but 1 jumbo HDLC of needs configuration of Main Processing Unit pond like this.With a standard V5.2 interface and 32 remote terminations is example, when employing focuses on mode, Main Processing Unit 1 needs about 80 road HDLC circuit of configuration, and if adopt distribution process mode of the present utility model, then 1 of Main Processing Unit needs about 16 road HDLC circuit of configuration to get final product.

High speed serial ports 5 is continuous in the mode of bus, this means that its bandwidth is shared by the polylith veneer, is example with 20 veneers, and total bandwidth is that the high speed serial ports 5 average broadbands of every veneer of giving of 1.25Mbit/s have only 62.5Kbit/s.The point-to-point mode that high speed serial ports 5 is connected into as shown in Figure 4 can make the effective bandwidth of every veneer all reach 1.25Mbit/s, and this moment, Main Processing Unit 1 did not need to dispose the HDLC circuit, but needs to dispose nearly 20 tunnel high speed serial ports 5.A kind of desirable scheme is that veneer is divided into groups, such as being one group with per 5 veneers, share a high speed serial bus 5 for every group, 1 needs configuration of Main Processing Unit, 4 tunnel high speed serial ports 5 get final product like this, this moment, the serial ports bandwidth of average every veneer can reach 250Kbit/s, and this bandwidth is enough for the message transmission between Main Processing Unit 1 and the Digital Trunk Board 3.

Can also be connected into National Federation of Trade Unions's line mode between the veneer, as shown in Figure 5.The characteristics of National Federation of Trade Unions's line mode are that single-board slot is general, are convenient to carry out the function expansion by increasing the veneer kind, and shortcoming is that hardware cost is higher relatively.For TDM interface 4 is connected into bus mode, also need on the Digital Trunk Board 3 to insert a multiplexer circuit at TDM interface 4 places, be used for from the TDM bus many to data wire choose wherein 3 be docked to little switching matrix 8.

The quantity of Digital Trunk Board 3 depends on the quantity and the capacity of institute's band distal end node.Converge to example with 4: 1,, need nine Digital Trunk Boards 3 altogether for the situation of ten distant-end nodes, each node 200 line; And, then only need two Digital Trunk Boards 3 for the situation of four distant-end nodes, each node 100 line.Like this, network capacity is big more, and then the quantity of Digital Trunk Board 3 is just many more, and the quantity of HDLC circuit 9 is also many more; Otherwise network capacity is more little, and then the quantity of Digital Trunk Board 3 is just few more, and the quantity of HDLC circuit 9 is also few more.Therefore, the utilance of the utility model HDLC circuit 9 does not change with the variation of network capacity substantially, and the cost of average every subscribers feeder is relatively stable.And the existing digital loop carrier equipment central office terminal that focuses on mode, because its all HDLC circuit is all on Main Processing Unit, it does not change with the variation of network capacity, therefore the utilance of hour HDLC circuit is low in network capacity.

Claims

1, a kind of distribution process formula digital loop carrier equipment central office terminal, it comprises Main Processing Unit (1), interconnection plate (2) and Digital Trunk Board (3), link to each other with high speed serial ports (5) by time division multiplexing tdm interface (4) between them, it is characterized in that, dispose the advanced data link controller HDLC circuit (9) that can on relaying E1 interface (6) message channel, directly extract or insert message flow on the described Digital Trunk Board (3).

2, distribution process formula digital loop carrier equipment as claimed in claim 1 central office terminal is characterized in that, disposes little switching matrix (8) on the described Digital Trunk Board (3).

3, distribution process formula digital loop carrier equipment as claimed in claim 1 central office terminal is characterized in that, disposes No. four relaying E1 interfaces (6) and No. eight advanced data link controller HDLC circuit (9) on the described Digital Trunk Board (3).

4, distribution process formula digital loop carrier equipment as claimed in claim 1 central office terminal is characterized in that, described high speed serial ports (5) adopts the serial ports form of MCS51 single-chip microcomputer (N15).