JPH0267842A - Lan node and lan system - Google Patents

Abstract

PURPOSE:To reduce the amount of hardware of a node by providing a ring access function part with the exchanging function and deciding relaying or reception of slot information on the node. CONSTITUTION:A higher-order LAN (local area network) 201 consisting of LAN nodes 1 to 4 and a transmission line 220 stores lower-order LANs 202 and 203 a camera 214, and a monitor 215. Each of nodes 1 to 4 is provided with (NXL)-number of switches (N and L are integers and N is equal to or smaller than L), whose number corresponds to (the number of inputs) X (the number of outputs), to provide the exchanging function by which a slot header is used to exchange the destination of reception slot information from each ring to the node itself (reception) or another node (relaying), and relaying or reception of slot information is decided on each of nodes 1 to 4. Thus, the amount of hardware of the multiring LAN node is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a ring LAN system and its node configuration, and more specifically, to a multi-ring LAN system suitable for high speed.
This relates to the exchange method at the node. [Prior art l] Regarding conventional multiple ring LAN nodes, for example, a 5E85-12-fiber tard structure is described in IEICE exchange study group materials, and
The exchange method is described in the 163753 publication. [Problems to be Solved by the Invention] In the above conventional method, in an n-multiple ring configuration in which a plurality of nodes are connected by a plurality of slotted rings, each node once receives the slots on each ring into a buffer memory corresponding to the ring, After that, a slot destined for the own node is selected within the buffer memory. Furthermore, during transmission, the information to be transmitted by each node is stored redundantly in the transmission buffer memory of each ring, and the earliest available empty slot is used to transmit without duplication. According to the above method, each node requires a total of 20 outputs: n outputs for relaying on the ring and n outputs for filling the ring-compatible reception buffer. The value of n is generally 16~
Therefore, in the conventional system, as the number of nodes increases, the number of inputs and outputs of the nodes and the amount of hardware increase dramatically, and the usage efficiency of the transmission buffer decreases. An object of the present invention is to suppress the increase in the amount of hardware of the above-mentioned multi-ring LAN node. [Means for Solving the Problems] The above-mentioned conventional problem is that a plurality of transmitting/receiving functional units are provided for each ring in the ring access functional unit in each node, and the actual exchange function is not provided in the transmitting/receiving functional unit. This is due to the fact that Therefore, in the present invention, each node is provided with a transmitting/receiving function unit for the own node that is common to the ring, the ring access function unit is provided with an exchange function, and the node determines whether or not to relay and receive slot information. Achieve the above objectives. [Operation 1] According to the present invention, by providing NXL switches corresponding to (number of inputs) x (number of outputs) in the notebook, slot information received from each ring is addressed to the own node using the slot header. (reception) and exchange to other nodes (relay). Furthermore, when sending slot information,
It is possible to transmit to any ring from one transmit buffer. In addition, when transmitting the above, if you control the transmission to the ring with the lowest traffic, you can improve the transmission efficiency, and if you control the transmission to a specific ring that corresponds to the destination node, the reception Since the node receives only from a specific ring, the maximum reception speed is limited to one ring speed, which reduces the node operating speed. Further, according to the present invention, by assigning a call number that can identify the source and destination between communication nodes out-of-band during system setup, the call number can be used as switch information in the slot header during subsequent data transfer. Can be done. Also,
By providing priority information in the slot header, controlling all high priority slots to be processed, and setting the priority of relay slots higher than that of transmission slots, it is possible to reduce the intra-node delay associated with relaying. . Example 1 An example of the present invention will be described below with reference to the drawings. FIG. 2 is an overall configuration diagram of a network system to which the present invention is applied, in which LAN nodes 1.2.3, 4. The upper LAN 201 composed of the lower LA and the transmission line 220 is
It accommodates N202, 203, a camera 214, and a monitor 215. Further, the lower LANs 202 and 207 include nodes 204 and 205 . and via 206 and 207,
LAN terminals 212, 213. 211 and 210 are connected to each other. The present invention relates to the construction of the upper LAN 201 and the nodes 1.2.3.4 connected thereto in the network system, and the type of connection media is not essential. Figure 1 shows the node structure. The node 1 is connected to a transmission line 220 made of an optical fiber via an optical/electrical converter 12 and an electric/optical converter 15. A LAN frame consists of 15 channels, including a separation section 13 that separates the frame header and divides the channels, a multiplexing section 14 that performs reverse reproduction, and a 16X channel that exchanges each channel.
16 switches 10 and a user equipment interface 11
It is made up of. Of the 16 inputs and outputs of the switch 10, 15 each indicated by 22 and 23 are connected to the separating section 13 and the multiplexing section 14, respectively, and each 1 indicated as 20 and 21 is connected to the separating section 13 and the multiplexing section 14, respectively.
Inputs and outputs are connected to the user equipment interface 11. The exchange and transmission/reception procedures within the switch 10 will be explained using FIG. 1O-1(i) to 10-16(i) and 10-1(o)-10-16(o) are 16 input/output channels corresponding to 20, 22, 21, and 23 in Fig. 1, respectively. It shows. 10-k (i) (k =
The slot information input in 2 to 16) is 1O-1(o) if it is addressed to the own node, and 1 if it is addressed to another node.
It is output (exchanged) to Ok(o). In this embodiment, a method is adopted in which the slot information is deleted at the receiving node, but in the case where the slot information is deleted at the transmitting node, each slot information is divided into two pieces of Pi, one of which is 1O-1(o). and the other is output to 1O-k(0). Note that the destination of each slot can be identified by the call number 40.41, which will be described later in FIG. The transmission slot information input to 1O-1(i), excluding broadcast information, is sent to 1O-1(o) if it is addressed to the own node.
If it is addressed to another note, 1O-k (
o) and sent out. In this embodiment, for example, 1O-2(o) is sent to the LAN node 4 shown in FIG.
1O-3(o) to AN node 3, lO-4(o) to 9(o) to LAN node 2, LAN node 1
10-10 (o) to 16 to the destination, that is, to the own node
(o) respectively. Among the plurality of output channels, a channel with a low usage rate is selected based on the result of monitoring the slot usage rate. In the case of broadcast information transmission, a broadcast call number as shown in FIG. 5 is assigned and copies are transmitted to all channels. When transmitting, since a user frame such as a LAN frame has a maximum length of 4 bytes, it is divided into user areas 44 in FIG. 4 and transmitted. For this reason, for example, 10-10 (o) to 16 (o) can be used when addressing node 1, but in order to prevent the order of slot information generated from the same user frame from being overtaken by slots, the first It is controlled to output to the same channel as the slot transmission channel. Figure 4 shows the LAN adduction/adduction/rolot slot format. The entire format consists of a header 50 and information 51, and has a total length of 36 bytes. Outband call setup information 440
When the call is transferred, the user area 44 shows the call setting information 440. At the time of data transfer, the call number assigned during call setup is set to call number 40.41. The control information 42 includes call number error detection information, priority information, etc. The 0 division number 43 includes 2 bits for distinguishing between the beginning, the middle, and the last slot in a user frame when slots are divided; It consists of 6 bits indicating the effective information length bit. The call control information 11440 includes protocol 1 to protocol identifier 441 indicating the protocol type according to the following format. Target call number 442゜44 for rqL setting or cancellation
3, a message type 444 indicating the type of control such as call setup or cancellation, additional information 445, and FC 5446. Further, the additional information 445 includes an information element identifier 447, an information element length 448, and information content 449. FIG. 5 shows the call setting method between nodes and the assigned call numbers. Each node has a group of call numbers 6 assigned to all other nodes in ascending order of node addresses during system setup.
1 to 76 are set using the call setting information 440 in FIG. In addition, out-of-band control information is realized by broadcasting.
A broadcast control call number 77 and a broadcast data call number 78 are set in advance. In this embodiment, since the maximum number of FIJ-connected nodes is 64 nodes, 64 call number groups are assigned to one node, including those addressed to the own node. Note that one call number group consists of 15 call numbers, which are used as user boat numbers. For example, for self-addressed communication from node 1 to node 1 (OOOO) 0. The call number group 61 of . . . . . . . . . . . . . . . . Broadcast call number 77 is (
OOXF), (X=0-F). The broadcast data 78 is (FFXF), (X=O to F). FIG. 6 shows a functional block diagram of the switch 10 of this embodiment. The slot information is serial-parallel converted by the optical/electrical converter 12 in FIG. be done. The header portion of each slot is connected to a read address terminal (RA) of the relay table 171. Also, the data output (D
O), new headers (input and output call numbers use the same call number) and in-use information are stored in the common buffer 17.
0 data input (DI) and a write enable input (WE) via gate 172, and the outgoing line number is connected to the destination outgoing line number input (DES) of address pointer 173. The data output (DO) of the empty address PIFO 174 is connected to the data input (DI) of the common buffer 170 and the next data damage address input (NWAD) of the address pointer 173.
), and the empty display output (EPTY) is connected to gate 17.
Write permission input (W
E). The write address output (WAD) of the address pointer 173 is connected to the write address input (WA) of the common buffer 170, and the read address output (RAD) is connected to the read address output (RA) of the common buffer 170 via the selector 175. ) and the data input of the empty address PIFO 174. Empty cell address register 176 is connected to selector 175. Next, the operation of writing slot information into the common buffer will be explained. The schematic structure of the input slot is shown in Figure 7(a).
Its detailed structure is shown in FIG. Using the call numbers 40.41 in the header 50 as input information, the slot usage status and outgoing line number are obtained from the relay table 171. Figure 7 (
b) shows the output of the relay table 171. The outgoing line number is input to the address pointer 173, and an appropriate write address for writing to the common buffer 170 is obtained accordingly. The write address is given in advance from the empty address FIFO. Note that if the slot is empty, it will not be written to the common buffer and the write address will not be updated. The data output of the empty address FIFO is stored in the common buffer 170 along with the slot information, thereby chaining the slot information for each same outgoing line in the common buffer. Furthermore, this chain is formed on the priority side determined by the intra-switch priority information 54, and the chain with the highest priority is read out in all processing. Effects of the Invention 1 According to the present invention, it is possible to provide the ring access function section with an exchange function and to determine whether or not to relay and receive slot information on the node. The number of user connections can be reduced to the sum of the number M and the number of user connections CL-M). In addition, when the number of transmission buffers is equal to the number of user connections < (LM) = 1, it is possible to reduce the amount of hardware in the node to 1/(number of multiplexed rings) compared to the conventional method. Become.

[Brief explanation of the drawing]

FIG. 1 is a schematic block diagram of a LAN node according to the present invention;
Fig. 2 is an overall diagram of a LAN system to which the present invention is applied, Fig. 3 is an explanatory diagram of intra-switch exchange and transmission/reception procedures, Fig. 4 is a LAN adduction/adduction/loss slot format, and Fig. 5 is an inter-node call setting method and assigned call. Numbered diagram, Figure 6 is a functional block diagram within the node,
FIGS. 7(a) to 7(c) are diagrams showing a schematic format of a note input slot, an output format of a relay table within a switch, and a data structure within a shared buffer, respectively. 1... Upper LAN node, 10... Channel exchange switch, 11... User equipment interface. 12... Optical/electrical conversion section, 13... LAN frame separation section, 14... Frame multiplexing section, 15. Electrical/optical conversion section. Figure 3 Figure 5 75: (OC20) +6 ~ (OC2E) 1676
: (OC30h6~(OC3E)1677:i-ssf
t1lt'lf wholesale (OOXF) 1678, broadcast data (FFXF) 1s Fig. 7

Claims (1)

[Scope of Claims] 1. Each device is connected to the same medium, and each transmits transfer information to which destination information is attached, and also compares its own station identification number and input destination information, and if they match, transfers the transfer information. In a LAN (local area network) node that operates to receive, (number of inputs) x (number of outputs) is N x L.
(N, L are integers, N≦L) switches, M transmission lines (M is an integer, M<N) that connect to the input and output of each switch, and (NM) switch inputs and L characterized in that (LM) switch outputs are connected to the user equipment.
AN node. 2. Connected to the same medium, each transmits transfer information with destination information attached to the medium, compares its own station identification number and input destination information, and operates to receive transfer information if they match. In a LAN (local area network) node, (number of inputs) x (number of outputs) is N x L
(N, L are integers, N≦L) switches, and 1×M and M×1 (M is an integer, M<N) transfer information multiplexing/demultiplexing units before and after the switches; A LAN node, characterized in that ) switch inputs and (LM) switch outputs are connected to user equipment. 3. In the switch according to claim 1 or 2, one of the switch inputs is connected to one of the (LM) outputs connected to the user device or M of a predetermined transfer information multiplexing unit. What is claimed is: 1. A LAN node characterized in that it has a switch that replaces one of the nodes. 4. In the switch according to claim 1 or 2, the input transfer information from the user device is exchanged to the output with the lowest traffic among M outputs connected to the transfer information multiplexing section or the transmission line. A switch characterized in that it operates as follows. 5. In the switch according to claim 1 or 2, the input transfer information from the user device is transferred to a transfer information multiplexing section or an output predetermined according to the destination node among the M outputs connected to the transmission path. A switch characterized in that it operates to replace. 6. In claim 4 or 5, when user information is divided into a plurality of transfer information and transmitted, a switch is controlled so that transfer information belonging to the same user information is output to the same output. A LAN node characterized by: 7. Through outband call control, in a LAN node that has a switch that performs exchange and statistical multiplexing of fixed-length mini-packets with a pre-allocated call number in the header, prior to sending forwarding information, the LAN connected to the same medium A LAN system characterized by setting one or more call numbers used for communication between nodes, and performing inter-node communication using the call numbers. 8. A LAN system according to claim 7, characterized in that broadcast call numbers addressed to a plurality of nodes are simultaneously assigned. 9. In the LAN node according to claim 1 or 2, when broadcasting, the broadcast information is copied to a plurality of outputs of the switch, and the broadcast call number according to claim 8 is copied to the multiple outputs of the switch. A LAN node characterized in that a LAN node transmits data by attaching a . 10. When installing a LAN node, a LAN node number that is less than or equal to the maximum number of connected LAN nodes is assigned to each LAN node in ascending or descending order, and the call number area is divided into the maximum number of connected LAN nodes. When setting up a call in Clause 7, the call number divided to the own node is sent to all node numbers less than the own node number, or to all node numbers greater than the own node number and less than or equal to the maximum number of connected LAN nodes. A LAN node characterized in that: 11. The switch according to claim 1 or 2 gives priority to higher-priority transfer information over lower-priority transfer information among transfer information output to the same output, according to the priority information set in the transfer information. In a LAN node that has a switch that outputs a
A LAN node characterized by assigning a lower priority than internal transfer information and deleting the priority information when outputting from a switch. 12. The switch according to claim 1 or 2 gives priority to higher-priority transfer information over lower-priority transfer information among transfer information output to the same output, according to the priority information set in the transfer information. In a LAN node having a switch that outputs the information, the output transfer information from the user equipment is transmitted with a lower priority than the intra-LAN transfer information, and is converted to a higher priority when transmitted from the LAN node.
N node. 13. A private ring topology LAN system characterized by using the same transfer format as the asynchronous transfer format in broadband ISDN.