JPS5870660A - Data communication system - Google Patents

Abstract

PURPOSE:To limit a packet from flowing to a network, by providing an access with different priority to a packet transmission of virtual or data graph type. CONSTITUTION:A packet data incoming from a terminal device 1 to a network transmitter and receiver 2 has discriminating information for packet classification and the classifications of packets are discriminated at a discriminating means 21. When the packet is a virtual call type and a call set packet, a timer of a call set abolishing means 23 is started, and the discrimination information and the packet are applied to a priority provision means 22, where the 3rd priority is provided and transmitted to a data communication network 3. When the packet is the virtual call type and a packet other than the call set packet, or a data graph type packet, the 1st or 2nd priority at the means 22 and the packet is transmitted to the network 3. The packet classification are discriminated for the packet received from the network 3 at a discriminating means 24, a response packet is provided at a response packet forming means 25 and the priority is given at the means 22.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a transmission method with priority in a data communication network capable of transmitting packetized data.In a packet data communication network, data is transmitted to multiple nodes as shown in FIG. As shown in Figure 2, there are two types of communication between predetermined terminals that are transferred through the terminal, and those that share the rl glossy medium and that collide with the medium via the data expansion transmitting/receiving device transmitted from the terminal. There are things that are accessed to prevent this from happening.

On the other hand, data sent to a data communication network may be such as voice communication, which needs to be transferred continuously with a relatively small delay once sent, or time-sharing systems, where some delay is allowed. However, in both the network shown in Figure 1 and the network shown in Figure 2, packets are waiting for transmission, so if a large amount of data comes in from each terminal almost simultaneously, the overall transmission delay will increase. The object of the present invention is to eliminate the above drawback by combining priority control in the network and flow rate restriction at the data transmission end.
Our goal is to provide data communication methods that suit each application.

Conventionally, there are two types of packet transmission: the virtual call type, in which a series of packets to be transmitted is configured into one logical channel by setting up a call, and the packets are transmitted, and the datagram type, in which each packet is transmitted independently. There is.

In the present invention, virtual call type packet transmission is performed for data that requires little delay, datagram type packet transmission is performed for data that can tolerate some delay, and datagram type packet transmission is used for virtual call type transmission. The transmission delay is reduced by giving higher priority than the transmission of . However, if such a method is used, only virtual call type transmissions will be prioritized and datagram type transmissions will be ignored, or if virtual call type transmissions increase rapidly, However, there are problems such as a large transmission delay may occur. To solve this problem, it is necessary to restrict the inflow of virtual call type transmissions. As one method for limiting inflow, in virtual call type Nonoket transmission, it is possible to abandon a call depending on the response time at the time of call setup. In other words, in this case, the amount of traffic flowing into the network is measured based on the call setup response time. However, even if the call setup response time is a certain amount of traffic, it is distributed over a certain time range, so it cannot necessarily be said that it is an accurate traffic estimation.

If priority control is introduced and the priority of call setting packets is lowered relative to other packets F, the distribution of response times of call setting packets will become smaller and traffic setting will become more accurate. Therefore, as a priority level, a normal packet of a virtual call type is the first, a datagram type packet is the second, and a call setup packet of the virtual call type is the third. With such priority leveling, it is possible to perform communication without causing a large delay in virtual fool type transmission and in which datagram type packet transmission is not ignored. As described above, the present invention provides a data communication network including a degenerate receiving device equipped with a means for prioritizing calls based on packet types and a means for abandoning calls based on response times, or a preferential access means prioritized according to packet types and a means for abandoning calls based on response times. The present invention provides a data communication system that configures a data communication network that includes a degenerate receiving device equipped with a degenerate receiver and that shares one medium to perform packet transmission.

Next, the present invention will be explained in detail with reference to the drawings.

FIG. 3 is an example of a data communication network using the data communication system of the present invention. In the figure, degenerate receiving device 1 and degenerate receiving device j
2 is a device that can receive both a virtual call type and a datagram type, and a degenerate receiver 3 and a degenerate receiver 4 are devices that can receive only a partial call type packet. The degenerate receiver 5 and the degenerate receiver 6 are devices that accept only datagram type 1 packets, and the degenerate receiver 7 is also capable of receiving other types of packets. The network or medium is capable of communication with at least three unique priorities, and each degenerate receiving device is capable of connecting to the network or medium with the appropriate priority, and each Communication can be performed between devices. Here, devices that can be connected to each other have the same packet format.For example, degenerate receiving device 1 can be connected to each degenerate receiving device from device 2 to device 6, and network 2 transmitting/receiving device 3 can connect to degenerate receiving devices 2 to 6. 4 or devices 1 and 2, and degenerate receiving device 5 can be connected to device 6 or devices 1 and 2. It is possible to connect to datagram packets of 1.2. It is also possible to connect other types of packets or those with different priorities, such as device 7. .

Below, the configuration of each degenerate receiver will be described in more detail.

FIG. 4 shows a first embodiment of the degenerate receiving device of the present invention.

In the figure, packet data entering the degenerate receiving device 2 from the terminal device 1 has identification information of the packet type, and the determining means 21 determines the type of the packet. If the packet is of the virtual call type and is also a call setting packet, the timer of the call setting abandonment means 23 is started, and the determination information and the packet are sent to the priority adding means 22 which can assign priority levels in three ways. 3 at 22
It is given the highest priority and sent to the data communication network 3. If the packet is a virtual call type packet other than an FF & constant packet, or if it is a datagram type packet, the priority adding means 22 assigns the first or second priority to each packet and sends it to the network 3. A packet is sent to On the other hand, the type of packet received from the network 3 is determined by the determination means 24, and if it is a call setup request packet, a response packet is created by the response packet creation means 25, and the third priority packet is created by the priority addition means 22. It is assigned a priority and sent to the network 3. When the determination means 24 receives a response packet to the call setup, the timer of the call setup abandonment means 23 is reset and the packet is sent to the terminal 1. Further, if the packet determined by the determining means 24 is of a virtual call type and is not related to call setup, the packet is immediately sent to the terminal 1. When the timer of the call setting abandonment means 23 times out, the terminal 1 is notified of call abandonment. Here, response packet creation means 25
is not necessarily included in the degenerate receiving device, but may also be included in the terminal device.

Further, in a degenerate receiving device that can only accept datagram type packets, the determining means 21 and 24, the call setting abandonment means 23. And the response packet creation means 25 need not be included.

FIG. 5 shows a second embodiment of the degenerate receiving apparatus of the present invention.

In the figure, the packet type of packet data that enters the degenerate receiving device 102 from the terminal device ioi is determined by the determining means 121, and if it is a call setting packet, the timer of the call setting abandonment means 123 is activated, and the packet and determination information are is sent to the packet access means 122, and the means 122
medium 1 using the access means with the third priority.
03, and packets other than Virtual Fool type call setup packets or De-Tageram type packets are accessed by the packet access means 122, respectively, to the access means with the first or second priority. An attempt is made to access the medium 103 using the .

On the other hand, among the packets accessed to the medium 103, those addressed to the own station are received by the receiving means 126 and sent to the determining means 124.
sent to. The determination means 124 determines the type of the packet, and if it is a call setup request packet, a response packet is created by the production means 125, and the packet access means 122 assigns the third priority to the medium by the access means. 103 is attempted. Judgment means 12
When a response packet to the call setup is received in step 4, the timer of the call setup abandonment means 123 is reset and the packet is sent to the terminal 101. Further, if the pattern F determined by the determining means 124 is other than the above two, the packet is sent to the terminal. In addition to receiving the response packet described above, the means for controlling the reset of the timer can send information indicating that the call setting packet has been successfully accessed by the packet access means 122 to the call setting means to reset the timer. In this case, the need for a response packet to the call setup request packet is not particularly necessary for inflow restriction, and therefore the determination means 124 and the response packet creation means 125 are unnecessary in the degenerate reception device, and the reception means 1
All patterns F received at 26 are sent directly to the terminal device 101. In either method, when the timer of the call setting means 123 times out, the call setting means 12
3 notifies the terminal 101 of the call abandonment. Further, when the reset is performed by the packet access means, the packet access means is notified of the occurrence of a timeout, and the packet access for call setup is abandoned, and when the reset is performed, a call setup notification is made. Even when the response packet creation means 125 is used here, the means 125 is not necessarily included in the degenerate receiving device, but may be included in the terminal device. Further, in a degenerate receiving device that can only accept data duram type packets, the determining means 1211, the determining means 124, the packet access means 122. Also, the response packet creation means 125 is not required.

211 receives a packet from terminal 1 or terminal 101. The format of the packet coming from the terminal 1 or the terminal 101 differs depending on whether it is a virtual call type or a data durum type, and each is shown in FIGS. 7 and 8. Figure 7.

In the format shown in FIG. 8, each item other than information consists of a bit string of several pips.Furthermore, the type identification part distinguishes whether it is a partial fool or a data tag.

In FIG. 6, the extraction means 212 extracts the type identification part of the format shown in FIG. 7 or 8 from the packet that comes in from the terminal 211. This extraction can be performed by counting the number of bits that have passed since the flag bit of the packet.

The bit pattern extracted by the extraction means 212 is sent to the decoder 2
13 and the determination information is output to the terminal 214. If the extraction means 212 determines that the packet is of the virtual call type, the packet is further input to the extraction means 217 to extract the packet type part in the format shown in FIG. is output to terminal 214. Therefore, the signal output from terminal 214 is a 2-bit series. The packets output from the extracting means 212 and the extracting means 217 are delayed by the registers 219 and 215, respectively, and in the switching circuit 210, the output of the decoder 213 causes the packets from the register 219 to be delayed in the case of data tag 2m. In this case, the packet from register 214 is selected and output to terminal 216. Note that in a device that only accepts partial fool type packets, the extraction means 212 is unnecessary and the packets are directly extracted from the extraction means 21.
7 is input. Decoder 213, register 219. The switching circuit 210 is also unnecessary.

As explained above, the present invention has the effect that it is possible to restrict the inflow of packets to the network by configuring access with different priorities for virtual call type and data durum type packet transmission. It is particularly effective for use in data communication networks that include both those in which data is transmitted continuously at a substantially constant rate, such as when transmitting audio, and those in which data is generated in bursts.

[Brief explanation of drawings]

1 and 2 are diagrams for explaining the configuration of a data communication network, and FIG. 3 is a diagram showing the overall configuration of the present invention.
FIG. 4 shows a first embodiment of the present invention, FIG. 5 shows a second embodiment of the present invention, FIG. 6 shows an AWm example of the packet determination means used in the present invention, and FIG. Figure 7 is an example of the format of a virtual call type packet used in the present invention, and Figure 'M8 is an example of the format of a data duram type packet used in the present invention. In the figure, 1, 101 is a terminal device, 2, 102 is a vertical transmitting/receiving device, 3 is a data communication network, 1o3 is a medium, 21,
24, 121, 124 are determining means, 23, 123 are call setting abandonment means, 25, 125 are response packet creating means, 2
2 is a priority addition means, 122 is a panat access hand R1
126u packet receiving means, 212 and 217 are extraction means, 213° and 218 are decoders, 219 and 215 are registers, and 210 is a switching circuit. 4th Mouth 5 B

Claims (1)

[Claims] 1. In a data communication network capable of transmitting packetized data, there are at least three priority levels.
a network, at least one of virtual call type Novacut or data durum type packets, or a plurality of vertical transmission/reception devices capable of receiving packets from a terminal device including at least virtual call type packets and data durum type packets. Among the virtual call type packets that enter the vertical transmitter/receiver from the terminal device, the packets other than the bucket for call setup are given the highest level of priority, and data durum type packets are given the highest level of priority. means for transmitting a second level of priority to a packet for call setup among packets of a virtual call and a third level of priority for a packet for call setup to a network; It has a means for responding to a packet arriving from the network, and a means for abandoning the call establishment and sending abandonment information back to the terminal device if there is no response to the call establishment from the other station within a predetermined time. Characteristic data communication method. 2. In a data communication network in which packetized data is accessed by multiple vertical transmitting/receiving devices sharing one medium, one network has at least three priority levels, and a virtual call type packet or data duplex. A number of vertical transmitting/receiving devices capable of receiving packets from a terminal including at least one of type packets, or at least a partial call type packet and a data duram type packet, and a call setup request packet in virtual call type packet transmission. is provided with a means for returning a call setup abandonment to the terminal device when a call setup abandonment is received from the terminal device. A high priority level is used to access the network, a second priority level is used for datagram type packets, and a third priority level is used for call setup packets among virtual call type packets. The present invention is characterized by comprising a plurality of degenerate receiving devices capable of accessing the network with the second priority level and abandoning call setup if the network cannot be accessed within a predetermined time. data communication method. 3. In a data communication network in which packetized data is accessed from a number of degenerate receiving devices sharing one medium, there is a method for accessing a network with at least three priority levels, and a means for accessing a network from a terminal device to a virtual means for receiving at least one of a call-type packet or a datagram-type packet, or both a virtual call-type packet and a datagram-type packet, and receiving a call setup request packet from a medium in virtual call-type packet transmission; and a means for sending a call setup abandonment back to the terminal device in response to a call setup request from the terminal device. The network is accessed with the highest priority level for packets other than call setup packets, and the network is accessed with the second priority level for datagram type packets. Among the fool-type packets, call setup packets are accessed to the network at the third priority level, and if a response packet to the call setup request is not received from the network within a predetermined time, the call setup is abandoned. A data communication system characterized by being equipped with a plurality of degenerate receiving devices capable of