JP3020037B2 - Tour monitoring packet communication system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cyclic monitoring type packet communication system, and more particularly, to a method of connecting a transmission path to a plurality of communication nodes (Access).
Node) and can perform multimedia communication of data, voice, image, etc.
(Local Area Network), MAN (Metro-politan Are
a Network) and a communication system usable as a WAN (Wide Area Network).

[0002]

2. Description of the Related Art Conventionally, LAN technology is CSMA.
/ CD method, that is, data is transmitted after confirming that the transmission path is not in use, and when data transmitted by another communication node collides with the data, the data is detected and retransmitted. A method of controlling the network by circulating one data called a token representing the transmission right on the network, and only the communication node receiving the token can transmit data, and when transmission is completed, passing the token to the next communication node It has been known. In addition,
LAN is a local area network, MAN is a local area network, and WAN is a domestic (wide area) network. There is a difference in the distance between communication nodes to be connected. The above-mentioned methods have problems such as (a) transmission efficiency is not improved when there is a lot of traffic, and (b) it is difficult to perform high-quality voice and image communication in terms of delay time. On the other hand, in terms of transmission efficiency,
From the viewpoint that good delay characteristics can be obtained, a slotted ring system in which a transmission path is divided into fixed-length cells and access control is performed on each cell is being studied. There is a method proposed in Japanese Patent Application No. 63-50310, "Travel Monitoring Type Packet Switching Method". In this method, the communication state of the communication node is notified by rewriting the busy address (BA) area in the cell header, and a reset cell is generated.

[0003] In the conventional cyclic monitoring type packet switching system including the above-mentioned "cyclic monitoring type packet switching system", the busy address of the own communication node is described in a busy address information part in a packet received from the preceding communication node. drives out to have all communication nodes other than the own communication node was to detect that not communicating. For this mechanism to work independently for all communication nodes, all communication nodes must be assigned different busy addresses. In reality, the number of communication nodes that can be distinguished from each other by describing the busy address in the size of the busy address information part in the packet is determined, and connecting the communication nodes beyond that number Will not be able to. Also, if the busy address information part in the packet is increased in order to increase the number of communication nodes that can be connected, the ratio of the control information area to the entire cell increases, and the transmission rate of the user information with respect to the transmission rate decreases. Will do. SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to solve the above-described problems in the related art, increase the capability of the reset type communication system, and provide a reset type communication system. It is an object of the present invention to provide a tour monitoring type packet communication system capable of expanding the application area of the system. Another object of the present invention is to provide a tour monitoring packet communication system that enables more communication nodes than the number of communication nodes that can be described and described in a busy address information section to be connected to the communication system. Still another object of the present invention is to provide a traveling monitoring type packet communication system capable of reducing the size of a busy address information section used when a certain number of communication nodes are connected to a communication system. .

[0004]

SUMMARY OF THE INVENTION The above objects of the present invention are as follows.
A plurality of communication nodes having a window size register indicating a transmission packet number limit value and a transmission packet number measurement counter are connected by a transmission link, and a destination address of a destination communication node is set between any communication nodes via the transmission link. A control information area having an area for setting, and an area for setting a busy address of the own communication node during packet transmission, and a system for communicating a packet including a user information area for setting user information. In the cyclic monitoring type packet communication system in which the end of packet transmission is determined by a busy address in the packet, the communication node has a unique busy address in the communication system and is based on a determination result by the busy address in the transmission packet. First-class communication node with communication period reset function A communication system sharing a specific busy address in the communication system, comprising a second type communication node not having the reset function, and resetting a communication period in the communication system only by the first type communication node. This is achieved by a tour monitoring type packet communication system characterized by the following.

[0005]

In the traveling monitoring packet communication system according to the present invention, the communication nodes are divided into two groups, a first group is assigned an individual busy address for each communication node, and a second group is assigned a busy address. A common busy address is assigned to the communication nodes of the group, and each communication node rewrites the busy address according to its active state and non-active state, and finally, the communication nodes belonging to the first group described above. Since a packet describing the counter reset identifier was sent,
When it is possible to connect more than the number of communication nodes that can be distinguished by being described in the busy address information section in the packet to the communication system, and to connect a certain number of communication nodes to the communication system In addition, there is an effect that the size of the busy address information portion used can be reduced.

[0006]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a diagram illustrating a method of determining a busy address (hereinafter, also referred to as “BA”). In the figure, "0"
A specific BA shared by a plurality of communication nodes, "#
“N” is any one of the BAs uniquely assigned in the communication system, and “#X” is any of the BAs uniquely assigned in the communication system other than “#N”. .
The BA of the transmitted packet is determined according to the BA of the arriving packet and the state of the communication node according to FIG.
FIG. 2 is a diagram illustrating a format of a packet. The packet 10 used in the present embodiment includes a control information area 11 used for controlling packet transfer and a user information area 12 in which transmission information is described. The control information area 11 further includes a destination address information section 11a that describes the destination of the packet and a BA information section 11b that is used to detect the end of transmission of all other communication nodes. FIG. 3 is a diagram illustrating a configuration example of a communication system according to an embodiment of the present invention. In the figure, "A, B, C, D, E,
"F, G and H" indicate the destination address of the communication node, "1,
"2,3 and 4" are the only BAs in the communication system, "0"
Represents a specific BA commonly used by a plurality of communication nodes in the communication system. The communication packet limit value is the same value “2” for all communication nodes, and packets within the broken line are allowed to be transmitted during the current communication period (that is, the time until the next reset circulates the communication system). Packet. Packets outside the broken line cannot be transmitted in the current communication period because they did not fall within the limit value, and are packets transmitted in the next and subsequent communication periods. Note that “transmitted” means that the transmission has already been completed in this communication period, and “none” means that the information packet to be transmitted does not exist in the corresponding communication node.

[0007] In FIGS. 3 to 13, the destination address when transmitting information is described in the user information area 12 described above, and “empty” when transmitting information is not described, and “empty” in the control information area 11 described above. This is described in the destination address information section 11a. The BA information section 11b in the control information area 11 is rewritten according to the conditions shown in FIG. User information area 12
Is hatched when transmission information is described, and is blank when transmission information is not described. Reset is described as “reset”. A communication node having only one BA in the communication system is referred to as an “individual BA node” and a specific B node.
A communication node having A in common is referred to as a “common BA node”. FIGS. 4 to 8 show that the individual BA nodes send the last packet in the communication period and thereafter receive a packet describing the BA of the own communication node, so that all communication nodes have finished transmission. This shows an operation example in the case of detecting the fact and sending a reset in order to shift to the next communication period. First, FIG. 4 is a diagram showing a situation where the communication node F has received a packet addressed to its own communication node and has transmitted a packet addressed to the communication node C. FIG.
The communication nodes G and B rewrite the BA according to the BA rewriting condition shown in (1). The communication node C receives a packet addressed to the own communication node. FIG. 5 is a continuation of FIG. Since there is no information to be transmitted, the communication node C transmits an empty packet. Since there is information to be transmitted, the communication node G captures an empty packet and sends it to the communication node A. The communication node A receives the packet and transmits an empty packet because there is no information to be transmitted. The communication node B captures an empty packet because there is information to be transmitted. FIG. 6 is a continuation of FIG. Communication node B
Transmits the captured empty packet to the communication node D because there is information to be transmitted. Since there is no information to be transmitted, the communication node D sends out an empty packet. The communication node B detects that a packet describing the BA addressed to the own communication node has been transmitted, and transmits a reset as shown in FIG. FIG. 7 is a continuation of FIG. FIG. 7 shows a situation in which the communication node B has transmitted a reset and cleared the counter for measuring the number of transmission packets. FIG.
It is a continuation of FIG. FIG. 8 illustrates a state in which the communication system according to the present embodiment shifts to a new communication period and starts communication again.

FIG. 9 to FIG. 13 show that the aforementioned common BA node transmits the last packet in a certain communication period,
This is an operation example in a case where an individual BA communication node located downstream from the common BA node sends a reset instead of the common BA node . First, in FIG. 9, the communication node G receives a packet addressed to its own communication node, and the communication node A
FIG. 9 is a diagram illustrating a situation in which a packet addressed to the destination is transmitted. Since there is no information to be transmitted, the communication node A sends out an empty packet. Since there is information to be transmitted, the communication node B captures an empty packet and sends it to the communication node F. The communication node F receives the packet. FIG.
It is a continuation of. Since there is no information to be transmitted, the communication node F sends out an empty packet. Since there is information to be transmitted, the communication node H captures an empty packet and sends the captured empty packet to the communication node C. This packet transmitted by the communication node H is the last information packet transferred within the reset cycle. Communication node A
BA is rewritten to "1" according to the BA rewriting condition shown in FIG. The communication node C receives a packet addressed to the own communication node. FIG. 11 is a continuation of FIG. 10. In FIG. 11, the communication node C transmits an empty packet because there is no information to be transmitted. Since the communication node A has received the packet describing the BA1 of its own communication node, it sends out a reset as shown in FIG. In this communication period, the communication node that sent the last packet is the communication node H, but is located downstream from the communication node H,
The communication node A located at the most upstream of the individual BA nodes rewrites BA to “1” in FIG.
The communication node A has sent the reset in place of the communication node H. FIG. 12 is a continuation of FIG. 11. FIG.
FIG. 2 shows a situation where the communication node A has transmitted a reset and cleared the counter for measuring the number of transmission packets. FIG. 13 is a continuation of FIG. FIG. 13 illustrates a state in which the communication system according to the present embodiment shifts to a new communication period and starts communication again.

According to the above-described embodiment, a specific busy address is assigned in common in a communication system to communication nodes equal to or more than the number of communication nodes that can be distinguished by being described in a BA information section in a transmission packet. However, the communication node to which the common and specific busy address is assigned transmits a packet describing the counter reset identifier to the most upstream communication node among the individual BA nodes downstream of the communication node in place of itself. The transmission has the effect of clearing the counters of all communication nodes connected to the communication system and notifying that the next communication period has been reached. This allows
An advantage is obtained in that communication nodes can be connected to the communication system beyond the maximum number of communication nodes that can be connected by the conventional method. This also means that if a certain number of communication nodes are connected to the communication system, it is possible to reduce the length of the BA information part required for the connection. Note that the above embodiments are merely examples of the present invention, and it is needless to say that the present invention is not limited to these embodiments. For example, the ratio of the number of individual BA nodes to the number of common BA nodes is not particularly limited. The transmission link to which the packet monitoring system according to the present invention is applied is not limited to a single ring transmission link as shown in the above-described embodiment. It can be applied to links. In addition,
As for the distance setting on the transmission link between the first-type communication nodes (individual BA nodes) described in claim 4, for example, the distance between the communication nodes is measured in advance, and the individual B
A method of arranging the individual BA nodes so that the distance between the A nodes is equal can be used, but is not necessarily limited to this.

[0010]

As described above in detail, according to the present invention, the capability of the reset type communication system can be increased.
In addition, there is a remarkable effect that it is possible to realize a tour monitoring packet communication system capable of expanding the application area of the reset communication system. More specifically, according to the present invention, it is possible to implement a tour monitoring packet communication system that enables more communication nodes than the number of communication nodes described in the busy address information section to be connected to the communication system. In addition, when a certain number of communication nodes are connected to the communication system, a traveling monitoring type packet communication system capable of reducing the size of the busy address information part used can be realized.

[0011]

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a method of determining a busy address in a communication node in a communication system according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a format of a packet according to the embodiment;

FIG. 3 is a diagram illustrating a configuration example of a communication system according to an embodiment;

FIG. 4 is a part of a diagram showing an operation example of an individual BA node;

FIG. 5 is a part of a diagram showing an operation example of an individual BA node;

FIG. 6 is a part of a diagram illustrating an operation example of an individual BA node;

FIG. 7 is a part of a diagram showing an operation example of an individual BA node;

FIG. 8 is a part of a diagram showing an operation example of an individual BA node;

FIG. 9 is a part of a diagram showing an operation example of a common BA node;

FIG. 10 is a part of a diagram showing an operation example of a common BA node;

FIG. 11 is a part of a diagram showing an operation example of a common BA node;

FIG. 12 is a part of a diagram showing an operation example of a common BA node;

FIG. 13 is a part of a diagram showing an operation example of a common BA node;

[Explanation of symbols]

10: packet, 11: control information area, 11a destination address information section :, 11b: BA information section, 12: user information area.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-1-223852 (JP, A) JP-A-3-10433 (JP, A) JP-A-3-205934 (JP, A) 1991 Spring Meeting of the Society of Japan B-496 (58) Fields surveyed (Int. Cl. ⁷ , DB name) H04L 12/42 H04L 12/56 JICST file (JOIS)

Claims (4)

(57) [Claims] A plurality of communication nodes each having a window size register indicating a transmission packet number limit value and a transmission packet number measurement counter are connected by a transmission link, and destination communication is performed between arbitrary communication nodes via the transmission link. A packet including a control information area having at least an area for setting a destination address of a node and an area for setting a busy address of the own communication node during packet transmission, and a user information area for setting user information In a cyclic monitoring type packet communication system in which a packet transmission end of another communication node is determined based on a busy address in the packet in the communication system, the communication node has a unique busy address in the communication system; Communication period reset function based on the judgment result by the busy address in the packet A first-type communication node, and a second-type communication node that shares a specific busy address in the communication system and does not have the reset function, and the communication is performed only by the first-type communication node. A traveling monitoring type packet communication system, characterized in that a communication period in the system is reset. 2. The communication node of the first type has a unique busy address in the communication system, and a measurement result of the transmission packet number measurement counter is within a transmission packet number limit value of the window size register, and In the case where the information packet to be transmitted remains (active state), the busy address setting area in the packet received from the communication node located before the own communication node in the packet transmission direction on the transmission link A function of setting an individual busy address of its own communication node and transmitting the packet to the next communication node, and whether the measurement result of the transmission packet number measurement counter reaches the transmission packet number limit value of the window size register If there is no information packet to send (non-active state),
A function of transmitting the packet as it is to the next communication node if the individual busy address of the other first type communication node is described in the busy address setting area in the packet received from the communication node located at the preceding stage In the non-active state, if the specific common busy address of the second type of communication node is described in the busy address setting area in the packet received from the communication node located at the preceding stage, the busy in the packet Having a function of setting an individual busy address of the own communication node in the address setting area and transmitting it to the next communication node, and the second type of communication node shares a specific busy address in the system A busy address in a packet received from a communication node located at the preceding stage in the active state. A function of setting the common busy address in the communication setting area and transmitting the packet to the next communication node; and a function of directly transmitting the packet received from the previous communication node in the non-active state to the next communication node. 2. The packet communication system according to claim 1 , further comprising a function of transmitting the packet to a node. In wherein the communication system, tour monitoring type packet communication method according to claim 1 or 2, characterized in that to equalize the number of communication nodes of the second type between communication nodes mutually first kind . In wherein said communication system, tour monitoring type packet communication method according to claim 1 or 2, characterized in that equal distances on the transmission link between the communication nodes mutually first kind.