JPH0310541A - Priority exchange service control system - Google Patents

Abstract

PURPOSE:To secure a packet from a low level terminal equipment to be sent with a prescribed quantity at all times by applying transmission processing of the preset number of low level packets continuously when the preset number of high level packets are subjected to transmission processing continuously. CONSTITUTION:A transmission processing section 14 sends a packet of a transmission waiting queue 131 with priority and in the case of consecutive transmission, a counter 143 is incremented every time one packet is subjected to transmission processing and the counted value is compared with a high level consecutive transmission regulated value in a holding means 141 corresponding to packets during transmission at present and when they are coincident or the transmission queue is absent, the packet in a low level transmission waiting queue 132 is started. In the case of low level transmission processing, a counter 143 i incremented similarly at every packet transmission and the counted value and a low level consecutive transmission regulated value in a holding means 142 are compared, and when they are coincident, the transmission processing of the low level packet is terminated to apply the transmission processing of the packet of the high level transmission waiting queue 131.

Description

[Detailed description of the invention] [Summary] Priority service system i1'11 method in packet exchange in which when a packet with multiple priority levels is received, the one with a higher priority level is given priority and transmitted to another station.I1'11 method with different priority levels To provide a priority exchange service control method that guarantees that a predetermined amount of packets from low-level terminals are always transmitted even when a large number of packets from high-level terminals are manually transmitted when transmitting terminal buckets. For this purpose, it has a packet reception control unit that identifies packets with priority levels from terminals using an identification unit and queues them in a transmission waiting queue corresponding to the priority level, and allows continuous transmission for each priority level. and a transmission processing section including means for holding a regulation value of the number of packets, and a transmission counter for counting the number of packets to be transmitted, and the transmission processing section is set to the holding means of the corresponding level in order from the highest priority level. The configuration is configured to perform continuous transmission of the same number of packets.

[Industrial Field of Application] The present invention relates to a priority service control method in packet exchange in which, when a packet with a plurality of priority levels is received, a packet with a higher priority level is given priority and transmitted to another station.

In recent years, packet switching has become increasingly used.

Various terminal devices are connected to the packet switch, and various data are transmitted and received via the bucket switching network.

The packet switch is running a priority switching service that can perform transmission preferentially depending on the nature of the data to be transmitted. In this case, the terminal devices are assigned high and low priority levels, and the packet switching equipment transmits packets from terminal devices with a high priority level with priority over packets from terminal devices with a low priority level.

However, when data from a terminal with a high priority level continues to be sent, the transmission of data from a terminal with a low priority level is left waiting, and an improvement is desired.

[Conventional technology] FIG. 7 is an explanatory diagram of a conventional example.

In FIG. 7, 70 is a packet switch, 71 is a high priority level terminal (displayed as a high level terminal), 72 is a low priority level terminal (displayed as a low level terminal), and 73 is waiting for transmission of a high priority level packet. A queue 74 represents a wait queue for low priority level packets, and 75 represents a trunk line through which the packets are transmitted.

The transmission operation of the conventional example will be explained with reference to FIGS.

The packet ■ is input by ■ and sent from the low-level terminal 72 ■,
When ■ is input, each high-level transmission waiting queue 7
3 and is in a waiting state in the low-level transmission waiting queue 74.

Next, in this state, the packets ■, ■, and ■ in the high-level transmission waiting queue 73 are transmitted with priority, and then, when the packets in the high-level transmission waiting queue 73 disappear, the packets shown in FIG. As shown in FIG. 3, the packet ■ in the low-level transmission waiting queue 74 can be transmitted for the first time.

As shown in C1 of the same figure, during the transmission of packet ■, packet 7) is inputted as ■ and ■ from the high-level terminal 71 and stored in the high-level transmission waiting queue 73, and subsequent packets ■ to ■ are input from the high-level terminal 71. When the [phase] is input, the packet switch 70 continues to sequentially transmit the packets stored in the high-level transmission waiting queue 73, as shown in FIG.

As a result, the packet (2), which has been waiting from the beginning in the low-level transmission waiting queue 74, and the packet (2) input after that are not transmitted and remain on the trunk line.

[Problems to be Solved by the Invention] According to the conventional method described above, when a large number of high-level packets flow, even if they are sent to the line, they are always stored in the high-level transmission waiting queue. Since the packets are connected, there is a problem in that low-level packets remain queued in the transmission waiting queue, causing delays within the network.

The present invention provides a priority system that guarantees that a predetermined amount of packets from low-level terminals are always transmitted even when a large number of packets from high-level terminals are manually transmitted when transmitting packets from terminals with different priority levels. The purpose is to provide an exchange service control method.

[Means to solve the problem] FIG. 1 shows a basic configuration diagram of the present invention.

In FIG. 1, 10 is a packet switch, 11 is an interface with a terminal with a high priority level (referred to as high level), 12 is an interface with a terminal with a low priority level (referred to as low level), 13 is a packet exchange control part 1, 130
is a bucket identification part, 13I is a high-level transmission waiting queue,
132 is a low-level transmission waiting queue; 14 is a transmission processing unit;
Reference numeral 141 denotes a holding means for a high level continuous transmission regulation value, 142 a holding means for a low level continuous transmission regulation value, and 143 a transmission counter.

In the present invention, high-level packets are transmitted with priority over low-level packets, but at that time, if new high-level packets are consecutively transmitted for the number of preset limit values, , low-level packets are continuously transmitted up to a preset number.

[Operation] In FIG. 1, first, a constant numerical value N is set in the holding means 141 as a high level continuous transmission regulation value, and another constant numerical value M is set in the holding means 142 as a low level continuous transmission regulation value.

Each packet transmitted from a terminal is input to the packet reception control unit 13 via each interface 11.12, and the priority level is identified by the packet identification unit 130, and packets from high-level terminals and packets from low-level terminals are distinguished. The packets are queued in corresponding transmission queues 131 and 132, respectively. Note that the packets queued in these are packets to be sent to the same trunk line, and the packets to be transmitted to other trunk lines are queued in respective transmission waiting queues that are not routed.

The transmission processing unit 14 performs packet transmission processing according to the priority level, but it looks at the status of the transmission waiting queues 131 and 132 of the receiver reception control unit 13 and gives priority to packets in the transmission waiting queue 131 with a high level. and send. When transmitting high-level packets continuously, the counter 143 counts each time one packet is transmitted, and the high-level continuation of the holding means 141 corresponding to the contents of the counter 143 and the packet currently being transmitted is performed. Compare with transmission regulation value. If there is a match, or if there are no more high-level packets in the transmission queue, transmission of the packets in the low-level transmission queue 132 is started.

In low-level transmission processing, the counter 143 similarly counts each packet transmission, and compares the count value with the low-level continuous transmission regulation value of the holding means 142. If they match, the low-level packet transmission processing is terminated. Then, the packets in the high-level transmission waiting queue 131 are transmitted.

In this way, even if packets are continuously queued in the high-level transmission queue, a fixed number of packets in the low-level transmission queue are always transmitted, so it is possible to prevent delays within the network. .

[Embodiment 1] Fig. 2 is a block diagram of an embodiment of a packet switch according to the present invention;
FIG. 3 is a flowchart of queuing processing, FIG. 4 is an explanatory diagram of packet configuration, queuing configuration, regulation value and counter, and FIG. 5(a) is a flowchart of transmission request reception processing.
FIG. 5) is a transmission processing flow diagram, and FIG. 6 is a diagram showing an example of a specific transmission processing operation according to the present invention.

In FIG. 2, 20 is one packet switch (A node) in a packet switch network composed of multiple nodes.
, 201 is a line management unit that manages the sending and receiving of packet data to and from a partner node or terminal via a trunk line or a line from a terminal, 202 is a protocol processing unit that processes protocols such as packet format, and 203 is a link management unit that manages packet data transmission and reception with a partner node or terminal via a trunk line or a line from a terminal. 204 is a routing processing unit that selects a route for transmitting to a destination terminal or a trunk line; 205 is a priority exchange processing unit that processes transmission according to the priority level according to the present invention; 206 is the same as 201; 21 is a line control processing unit that performs processing for establishing a physical interface with the trunk line or the line to the terminal; 22 represents another B node connected via a trunk line.

In FIG. 2, each section other than the priority exchange processing section 205 is a conventionally known mechanism, and the contents of the processing flow of the priority exchange processing section according to the present invention will be explained using FIGS. 3 to 5 (b). do.

First, the queuing processing flow shown in FIG. 3 will be explained.

In the A node 20 in FIG.
After the processing in step 04, when a plurality of packets to be transmitted to a certain line are input to the priority exchange processing unit 205, the priority class of each packet is extracted (step 3 in Fig. 3).
0). In this case, the packet structure is as shown in FIG. 4A.

The packet consists of a leading F (frame) link header, a packet node, and a data body, and the F link header includes information on priority class (synonymous with priority level). This priority class is added at the source packet terminal (not shown) and sent to the node.

Next, in step 31, the packet is queued in a trunk line transmission waiting queue corresponding to the identified priority class (priority level).

Subsequently, in step 32, each queue length counter value (QiC
NT: Update i=1,2). In this case, a queue length counter is provided for each priority class, but as shown in Figure 4, an example is shown in which there are two priority classes, 1 (A level) and 2 (low level).

When a packet is queued in the queue for the corresponding priority class, the corresponding queue length counters QICNT,Q
Any one of 2CNT is incremented by 1 and the update is performed.

Next, in step 33, a transmission request reception process is started.

The transmission request reception processing flow is shown in FIG. 5(a), and its contents will be explained next.

In the transmission request reception process, priority class 1 is set to "
1" (step 40). Subsequently, transmission of the packet of priority class "1" is started and transmission processing is executed (step 41). When the transmission is completed, it is determined whether the "return information" set in the transmission process flow (FIG. 5(b)), which will be described later, is '0'' (step 42).
, is "0", the process ends; otherwise, the current priority class is incremented by 1 (step 43), and then the transmission process of the updated priority class is started (step 41).

Next, the transmission processing flow shown in FIG. 5(b) will be explained.
This process is executed in step 41 in FIG. 5(a) above.

Before this transmission process is executed, "M" is set as a high level continuous transmission restriction value. Similarly, the priority level is high/
When the level is low, r is the low level continuous transmission regulation value.
N (however, normally M>N), the regulation value is stored in a predetermined register as shown in FIG.

In addition, 5iCNT is provided as a continuous transmission counter that counts the number of buckets 1- when they are continuously transmitted, and when there are two priority levels, these counters are divided into S I CNT and 52CNT as shown in FIG. It is.

First, the queue length counter QiCNT of priority class i
(In this case, i = 1.2) is "0" or not (step 50). If it is "'O", it means that there is no packet waiting to be sent in the queue for that class. represent and end. If it is determined in step 50 that it is not “O”, the transmission counter 5i of priority class i
It is checked whether CNT is smaller than the regulation value M (step 51).

regulation (if it is smaller than aM, the line management section (Fig. 2 20)
6) Request to send a class 1 packet to Step 5
2), then the continuous transmission counter 5iCN of the class 1
Step 53) increment T by +1, queue length counter Q i
CNT is decremented by -1 (step 54).

After this step 54, the process returns to step 50 and similar processing is performed, and in step 51, the transmission counter S
i If CNT is not smaller than the regulation value M (if they match), the transmission of that class is forcibly terminated.
CNT is set to "0" (step 55). Next, it is determined whether priority class i is the final class or not (step 56).
,! If it is the end last, O is set in the return information (step 57); otherwise, 1 is set in the return information (step 58), and the process ends. This return information is used in the determination in step 42 of FIG. 5(a) explaining the transmission request reception process, and if it is "0", the transmission process is terminated, and if it is "B", the transmission request is sent to a class with a lower priority level. The bucket is sent.

FIG. 6 shows an example of a specific transmission processing operation according to the present invention.

In FIG. 6, 60 represents a bucket switch, 61 a high-level terminal, 62 a low-level terminal, 63 a high-level transmission waiting queue, 64 a low-level transmission waiting queue, and 65 a trunk line.

To outline the operation, as shown in A, when the continuous transmission restriction value M1 of the high-level bell-bake-note is set to "3" and the continuous transmission restriction value M2 of the low-level bell-bake-note is set to "'bi",
Packets such as ■, ■, ■, ■ are queued in the high-level transmission waiting queue, and ■, ■, etc. are queued in the low-level transmission waiting queue.
It is assumed that buckets such as , etc. are queued.

In this case, as shown in B, when packets ■ and ■5■ in the high-level transmission waiting queue are first transmitted, the count value of the continuous transmission bucket becomes 3, and it loses to Ml, so the high-level bucket Terminate the transmission and start transmitting low-level packets ■.

Since the continuous transmission limit value M2 of low-level packets is l, the transmission of low-level packets is finished, and then the transmission of high-level buckets is started as shown in C3 of FIG. Hereinafter, as shown in the same figure, when three high-level packets are transmitted, the operation of transmitting one low-level bucket is repeated.

Note that if the transmission bucket 1 of one level is not queued, only the bucket of the other level is transmitted.

[Effects of the Invention] According to the present invention, buckets with a lower priority level can flow smoothly within the network compared to the conventional system, and the conventional drawback of in-stream retention delay can be solved.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the principle configuration of the present invention, FIG. 2 is a diagram showing the configuration of an embodiment of a bucket exchanger according to the present invention, FIG. 3 is a queuing process flow diagram, and FIG. 4 is a diagram showing the bucket configuration, queuing configuration, and counter. FIG. 5(a) is a flow diagram of transmission request reception processing, FIG. 5(b) is a transmission processing flow diagram, and FIG. 6 is an example of a specific transmission processing operation according to the present invention. The figure shown in FIG. 7 is an explanatory diagram of a conventional example. In FIG. 1, 10: Packet switch 11.12 = interface 13; Bucket reception control section 130: Bucket identification section 131: High level transmission waiting queue 132: Low level transmission waiting queue 14: Transmission processing section 141: High level continuous Transmission regulation value holding means 142; Low level continuous transmission regulation value holding means 143: Transmission counter key

Claims (1)

[Claims] In a priority service control method in packet switching, in which when a packet with multiple priority levels is received, the one with a higher priority level is given priority and transmitted to another station, in which a priority level is assigned from a terminal. The packet is identified by the identification section (1
30) and queuing the packets in a transmission waiting queue (131, 132) corresponding to the priority level; (141, 142) and a transmission counter (143) that counts the number of transmitted packets (
14) A priority exchange service control system, characterized in that the transmission processing unit (14) continuously transmits a number of packets set in the holding means of corresponding levels in order from a high priority level.