CN113050703B

CN113050703B - Flow control method and device

Info

Publication number: CN113050703B
Application number: CN202110162901.0A
Authority: CN
Inventors: 翟颖颖
Original assignee: New H3C Technologies Co Ltd
Current assignee: New H3C Technologies Co Ltd
Priority date: 2021-02-05
Filing date: 2021-02-05
Publication date: 2022-11-18
Anticipated expiration: 2041-02-05
Also published as: CN113050703A

Abstract

The application provides a flow control method and flow control equipment. The method comprises the following steps: counting the number of the cache data messages of each virtual output queue; generating a first flow control protocol message for a first virtual port corresponding to a virtual output queue reaching a cache threshold; the first flow control protocol message is provided with a first indication Virtual Local Area Network (VLAN) identifier of a first virtual port; sending a first flow control protocol message to a first line card board where a first expansion port corresponding to the first virtual port is located; and the other equipment stops sending the data message to the first expansion port of the indication VLAN after receiving the first flow control protocol message.

Description

Flow control method and device

Technical Field

The present application relates to communications technologies, and in particular, to a method and an apparatus for controlling traffic.

Background

The centralized forwarding frame type switch is composed of a main control board and a line card board. The exchange chip of the line card board has a simple two-layer forwarding function, adds a board-to-board communication header with the information of the input port to the received data message, and then sends the data message to the main control board. The main control board executes the forwarding processing, and then packages the message after the forwarding processing into the inter-board communication header with the output port information and sends the inter-board communication header to the interface board. After the board communication head is stripped off, the interface board sends the forwarded message through the output port information.

In the centralized forwarding frame type switch, the line card board receives a Flow Control protocol message, such as a Pause frame or a PFC (Priority-based Flow Control) frame, and sends a main Control board through a cascade port, and the main Control board closes the cascade port that receives the Flow Control protocol message, so that a data message is no longer sent through the line card board that receives the Flow Control protocol message; or when a certain expansion port on the line card board is congested, the main control board closes the cascade port of the line card board connected with the congested expansion port; the main control board does not carry out end-to-end flow on the expansion ports on the line card board, so that the data message forwarding of other expansion ports on the line card board is interrupted.

Disclosure of Invention

The application aims to provide a flow control method and equipment, which are used for carrying out end-to-end flow control on an expansion port on a line card board.

To achieve the above object, the present application provides a flow control method, including: counting the number of the cache data messages of each virtual output queue; generating a first flow control protocol message for a first virtual port corresponding to a virtual output queue reaching a cache threshold; the first flow control protocol message is provided with a first indication Virtual Local Area Network (VLAN) identifier of a first virtual port; sending a first flow control protocol message to a first line card board where a first expansion port corresponding to the first virtual port is located; and the first line card board sends a first flow control protocol message with the first indication VLAN identification stripped through a first expansion port corresponding to the first indication virtual local area network identification.

In order to achieve the above object, the present application further provides a flow control device, which at least includes a statistics module, a storage module, a flow control module, and a sending module; a plurality of buffer quantity counters of the counting module respectively correspond to each virtual output queue of the storage module; the plurality of buffer quantity counters are used for counting the number of the buffer data messages of each corresponding virtual output queue; the flow control module is used for generating a first flow control protocol message for a first virtual port corresponding to the virtual output queue reaching the cache threshold value; the first flow control protocol message is provided with a first indication Virtual Local Area Network (VLAN) identifier of a first virtual port; and the sending module is used for sending a first flow control protocol message to the first line card board where the first expansion port corresponding to the first virtual port is located.

The beneficial effect of the application lies in that the main control board performs end-to-end flow control on the congestion expansion port on the line card.

Drawings

FIG. 1 is a flow chart illustrating an embodiment of a flow control method provided herein;

fig. 2 is a schematic diagram of a centralized forwarding frame device architecture provided in the present application;

FIGS. 3A and 3B are flow charts of embodiments of a flow control method under the architecture of FIG. 2 provided herein;

FIGS. 4A and 4B are flow diagrams of another embodiment of a flow control method under the architecture of FIG. 2 according to the present application;

fig. 5 is a schematic diagram of an embodiment of a device for flow control under the architecture shown in fig. 2 provided in the present application.

Detailed Description

A detailed description will be given of a number of examples shown in a number of figures. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present application. Well-known methods, procedures, components and circuits have not been described in detail so as not to obscure the examples.

The term "including" as that term is used is meant to include, but is not limited to; the term "comprising" means including but not limited to; the terms "above," "within," and "below" include the instant numbers; the terms "greater than" and "less than" mean that the number is not included. The term "based on" means based on at least a portion thereof.

FIG. 1 is a flow chart illustrating an embodiment of a flow control method provided herein; the method comprises the following steps:

step 101, counting the number of the cache data messages of each virtual output queue.

Step 102, generating a first flow control message with a first indication VLAN identifier of a first virtual port for the first virtual port corresponding to the virtual output queue reaching the cache threshold.

Step 103, sending a first flow control message to the first line card board where the first expansion port corresponding to the first virtual port is located.

The embodiment shown in fig. 1 has the beneficial effect that after the first line card sends the first flow control packet with the first indication VLAN identifier stripped through the first extension port corresponding to the first indication virtual local area network identifier, other devices connected to the first extension port stop sending data packets through the local port on the link connected to the first extension port, and perform end-to-end flow control on the congested first extension port on the first line card.

Fig. 2 is a schematic diagram of a centralized forwarding frame device architecture provided in the present application; in fig. 2, the expansion ports Port a and Port b of the line card board 0, the expansion ports Port C and Port d of the line card board 1, the Cascade Port (Cascade Port) U0 of the line card board 0, the Cascade Port U0 of the line card board 1, and the Cascade ports C1 and C2 on the main control board are physical ports. The cascade ports C1 and C2 in fig. 2 may be single physical ports, or aggregate ports formed by multiple member ports, which is not limited in this application

The method for controlling the flow rate under the architecture shown in fig. 2 and shown in fig. 3A includes:

step 301, assigning a virtual port and an indication VLAN for each expansion port.

The main control board allocates a virtual Port 0 and a VLAN100 to a physical Port a of the cable card board 0; port b is assigned virtual ports Port 1 and VLAN200, port c is assigned virtual Port 2 and VLAN300, port d is assigned virtual Port 3 and VLAN400, as shown in table 1:

expansion port	Virtual port	Indicating a VLAN	Cascade port
				Port a	Port 0	VLAN 100	C1
Port b	Port 1	VLAN 200	C1
				Port c	Port 2	VLAN 300	C2
Port d	Port 3	VLAN 400	C2

TABLE 1

Step 302, allocate the virtual output queue and port scheduler for each virtual port.

The main control board allocates a Virtual Output Queue (VOQ) to the Virtual ports Port 0, port 1, port 2 and Port 3, namely VOQ-1, VOQ-2, VOQ-3 and VOQ-4.

The master control board allocates a Port scheduler for virtual ports Port 0, port 1, port 2, and Port 3, as shown in table 2:

virtual port	Port scheduler
		Port 0	Scheduler 1
Port 1	Scheduler 2
		Port 2	Scheduler 3
Port 3	Scheduler4

TABLE 2

Step 303, setting a buffer count counter of each virtual output queue.

The counters allocated to the main control board for VOQ-1, VOQ-2, VOQ-3 and VOQ-4 are shown in Table 3:

virtual port	VOQ queue number	Counter with a counter body
			Port 0	VOQ-1	Counter-1
Port 1	VOQ-2	Counter-2
			Port 2	VOQ-3	Counter-3
Port 3	VOQ-4	Counter-4

TABLE 3

And step 304, notifying the indication VLAN of each expansion port to the line card board where each expansion port is located.

The main control board notifies the line card 0 of the indication VLAN100 and VLAN200 assigned to Port a and Port b, and notifies the line card 1 of the indication VLAN300 and VLAN400 assigned to Port c and Port d.

Step 305, counting the number of the buffered data packets of each virtual output queue.

The main control board is used for counting the data messages cached by each VOQ after the data messages enter or leave each VOQ through each counter.

Step 306, a flow control protocol message of the indication VLAN with a virtual port is generated for the virtual port corresponding to the virtual output queue reaching the buffer threshold.

In this embodiment, the flow control protocol packet is a packet frame with a time parameter field. When the Counter-1 count value reaches the caching threshold, the master control board generates a Pause frame with a time parameter of 0 and indicating the VLAN 100.

Step 307, sending a flow control protocol message to the line card board where the expansion port corresponding to the virtual port is located.

The main control board can know the cascade Port C1 corresponding to the virtual Port 0 according to table 1, and sends the Pause frame with the indication VLAN100 and the time parameter of 0 to the line card board 0 through the cascade Port C1. The line card board 0 receives the Pause frame, strips the indication VLAN100, and transmits the Pause frame through the expansion Port a corresponding to the indication VLAN 100. Therefore, after other devices connected with the expansion Port a receive the Pause frame, the other devices immediately stop sending the data message through the Port receiving the Pause frame according to the time parameter 0.

After the data messages of the VOQ-1 queue shown in the table 3 are forwarded by the switching chip of the main control board, the forwarded data messages leave the VOQ-1 queue, the data messages cached by the VOQ-1 are reduced, when the count value counted by the Counter-1 is lower than the cache threshold value, the main control board can generate a Pause frame with an indication VLAN100 and a time parameter of 1 for the virtual Port, the main control board can know a cascade Port C1 corresponding to the virtual Port 0 according to the table 1, and the Pause frame with the indication VLAN100 and the time parameter of 1 is sent to the line card board 0 through the cascade Port C1. The line card board 0 receives the Pause frame, strips the indication VLAN100, and sends the Pause frame with the time parameter 1 through the expansion Port a corresponding to the indication VLAN 100. Thus, other devices connected with the expansion Port a resend the data message after receiving the Pause frame with the time parameter 1.

The method for controlling traffic under the architecture shown in fig. 2 and shown in fig. 3B includes:

step 308, receiving the flow control protocol message with indication VLAN from the line card board.

In this application, if the Pause frame is sent by another device connected to the expansion Port b of the cable card board 0. The line card board 0 adds the indication VLAN200 corresponding to the received expansion Port b for the received Pause frame, and sends the indication VLAN through the cascade Port U1.

The master board receives the Pause frame with the indication VLAN200 from the line card board 0.

Step 309, opening or closing the port scheduler of the virtual port corresponding to the indication VLAN according to the flow control protocol packet.

If the time parameter of the Pause frame with the indication VLAN200 received by the main control board through the cascade Port C1 is 0, the Port scheduler of the virtual Port 1 corresponding to the indication VLAN200 is closed, and the data message is not sent through the corresponding expansion Port b of the virtual Port 1.

If the time parameter of the Pause frame with the indication VLAN200 received by the main control board through the cascade Port C1 is 1, opening a Port scheduler of a virtual Port 1 corresponding to the indication VLAN200, and recovering to send the data message through a corresponding expansion Port b of the virtual Port 1.

Through the embodiment shown in fig. 3A and 3B, the main control board performs end-to-end flow control on the expansion port of the line card board, thereby avoiding affecting data packet forwarding of other expansion ports on the line card board.

The method for controlling the flow rate under the architecture shown in fig. 2 and shown in fig. 4A includes:

step 401, allocating a virtual port and an indication VLAN for each expansion port.

The main control board allocates a virtual Port 0 and a VLAN100 to a physical Port a of the cable card board 0; port b is assigned virtual ports Port 1 and VLAN200, port c is assigned virtual ports Port 2 and VLAN300, and Port d is assigned virtual ports Port 3 and VLAN400, as shown in Table 1 above.

At step 402, a port scheduler for each virtual port is assigned.

The main control board allocates a Port scheduler for virtual ports Port 0, port 1, port 2, and Port 3, as shown in table 2 above.

Step 403, allocating each virtual port and virtual output queue of each service priority and queue scheduler.

For convenience of description, in the present application, taking service priorities T0-T4 as an example, a virtual output queue and a queue scheduler that are allocated by the main control board for each service priority corresponding to each virtual port are shown in table 4:

virtual port&Priority level	VOQ queue number	Queue scheduler
			Port 0，TC0	VOQ-1	TC Scheduler 1
Port 0，TC1	VOQ-2	TC Scheduler 2
			Port 0，TC2	VOQ-3	TC Scheduler 3
Port 0，TC3	VOQ-4	TC Scheduler 4
			Port 1，TC0	VOQ-5	TC Scheduler 5
Port 1，TC1	VOQ-6	TC Scheduler 6
			Port 1，TC2	VOQ-7	TC Scheduler 7
Port 1，TC3	VOQ-8	TC Scheduler 8
			Port 2，TC0	VOQ-9	TC Scheduler 9
Port 2，TC1	VOQ-10	TC Scheduler 10
			Port 2，TC2	VOQ-11	TC Scheduler 11
Port 2，TC3	VOQ-12	TC Scheduler 12
			Port 3，TC0	VOQ-13	TC Scheduler 13
Port 3，TC1	VOQ-14	TC Scheduler 14
			Port 3，TC2	VOQ-15	TC Scheduler 15
Port 3，TC3	VOQ-16	TC Scheduler 16

TABLE 4

Step 404, setting a buffer count counter of each virtual output queue.

The main control board sets a buffer count counter for each virtual output queue in table 4, as shown in table 5:

TABLE 5

Step 405, notifying the indication VLAN allocated to each expansion port to the line card board where each expansion port is located.

Step 406, counting the number of the buffered data packets in each virtual output queue.

Step 407, generating a flow control protocol packet with service priority information and indication VLAN for the virtual port corresponding to the virtual output queue reaching the buffer threshold.

In this embodiment, the Flow Control protocol packet is a PFC (Priority-Based Flow Control) Pause frame having a Pause time field. If the count value of Counter-12 reaches the buffering threshold, the main control board generates a PFC Pause frame with indication VLAN300 and traffic priority TC3 and Pause time not equal to 0.

And 408, sending a flow control protocol message to the line card board where the expansion port corresponding to the virtual port is located.

The main control board can know a cascade Port C2 corresponding to the virtual Port Port 2 according to the table 1, and sends the PFC Pause frame to the line card board 0 through the cascade Port C2. The line card board 1 receives the SFC Pause frame, strips the indication VLAN300, and transmits the SFC Pause frame through the expansion Port c corresponding to the indication VLAN 100.

Thus, after receiving the SFC Pause frame, the other devices connected to the Port c stop sending data packets with the service class TC 3.

After the data message cached in the VOQ-12 shown in table 5 is forwarded by the switching chip of the main control board, the forwarded data message leaves the VOQ-12 queue, the data message cached in the VOQ-12 is reduced, and when the count value counted by the Counter-12 is lower than the cache threshold value, the main control board can generate a PFC Pause frame with an indication VLAN300 and a service priority TC3 and with a Pause time equal to 0 for the virtual Port 2, and can know the cascade Port C2 corresponding to the virtual Port 2 according to table 1, and send the PFC Pause frame with the indication VLAN300 and the service priority TC3 and with the Pause time equal to 0 to the line card board 0 through the cascade Port C2. The line card board 0 receives the PFC Pause frame, strips the indication VLAN300, and transmits the frame through the expansion Port c corresponding to the indication VLAN 300. Thus, after receiving the PFC Pause frame, the other devices connected to port c of the expansion port resend the data packet of the service priority TC 3.

Fig. 4B illustrates a method for controlling traffic under the architecture illustrated in fig. 2, the method includes:

and step 409, receiving the flow control protocol message with the indication VLAN and the service priority information from the line card board.

In this application, if the PFC Pause frame with the service priority TC0 is sent by another device connected to the expansion Port d of the cable card 1. The cable card board 1 adds an indication VLAN400 to the received PFC Pause frame, and sends the PFC Pause frame through the cascade port U2.

The main control board receives the PFC Pause frame with the indication VLAN400 and TC0 from the line card board 1.

And step 410, opening or closing the queue scheduler corresponding to the virtual port corresponding to the indicated VLAN and the service priority information according to the flow control protocol message.

If the Pause time of the main control board receiving the PFC Pause frame with the indication VLAN400 and the TC0 through the cascade Port C2 is not equal to 0, the indication VLAN400 and the TC0 corresponding queue Scheduler TC Scheduler13 are closed, so that the data packet of the service priority TC0 is no longer sent through the corresponding expansion Port d of the virtual Port d. Because the Port controller of the virtual Port d is not closed, the expansion Port corresponding to the virtual Port d can still send data messages of other service priorities, and the end-to-end flow control based on the service priorities is realized.

If the Pause time of the main control board receiving the PFC Pause frame with the indication VLAN400 and the TC0 through the cascade Port C2 is equal to 0, the indication VLAN400 and the TC0 corresponding queue Scheduler TC Scheduler13 are opened, and the data message of the service priority TC0 sent through the corresponding expansion Port d of the virtual Port d is recovered.

Fig. 4A and 4B are simplified descriptions, and only TC0-TC3 of TC (Traffic Class) is taken as an example of the service priority, and the manner of the virtual output queue and the queue scheduler for each virtual port and TC0-TC7 is the same as that described above in the description, and details are not repeated.

FIG. 5 is a schematic diagram of an embodiment of an apparatus for flow control under the architecture of FIG. 2; the device 500 may be used as a master control board for a centralized forwarding box switch device. The apparatus 500 includes a processor, a switch chip, and a memory; the exchange chip is provided with a receiving module, a storage module, a sending module, a counting module, a flow control module, a configuration module and a notification module.

A plurality of buffer quantity counters of the counting module respectively correspond to each virtual output queue of the storage module; the plurality of buffer quantity counters are used for counting the number of the buffer data messages of each corresponding virtual output queue. The flow control module is used for generating a first flow control protocol message for a first virtual port corresponding to the virtual output queue reaching the cache threshold value; the first flow control protocol message is provided with a first indication virtual local area network VLAN identification of a first virtual port.

And the sending module is used for sending a first flow control protocol message to the first line card board where the first expansion port corresponding to the first virtual port is located. The setting module is used for distributing the virtual ports of the expansion ports and indicating the VLAN; distributing a virtual output queue and a port scheduler of each virtual port; and setting a plurality of buffer quantity counters corresponding to the virtual output queues. And the notification module is used for notifying the indication VLAN of each divided expansion port to the line card board where each expansion port is located. And the receiving module is used for receiving a second flow control protocol message with a second indication VLAN through the second line card board. And the flow control module opens or closes a port scheduler of a second virtual port corresponding to the second indication VLAN according to the second flow control protocol message.

The flow control module is further configured to generate a first flow control protocol packet and first service priority information for a first virtual port corresponding to the virtual output queue that reaches the buffer threshold. The sending module is further configured to send a first traffic control protocol packet with a first indication VLAN identifier and first service priority information to a first line card where a first expansion port corresponding to the first virtual port is located. The setting module is also used for distributing the virtual port of each expansion port to indicate the VLAN; a port scheduler for allocating each virtual port; distributing each virtual port and each virtual output queue of service priority and a queue scheduler; and setting a plurality of buffer quantity counters corresponding to the virtual output queues. And the notification module is further used for notifying the indication VLAN of each expansion port to the line card board where each expansion port is located.

And the receiving module is also used for receiving a second flow control protocol message with a second indication VLAN and second service priority information through the second line card board. And the flow control module is also used for opening or closing a second virtual port corresponding to the second indication VLAN and a queue scheduler of second service priority information according to the second flow control protocol message.

The present invention is not intended to be limited to the particular embodiments shown and described, but is to be accorded the widest scope consistent with the principles and novel features herein disclosed.

Claims

1. A method of flow control, the method comprising:

counting the number of the cache data messages of each virtual output queue;

generating a first flow control protocol message for a first virtual port corresponding to a virtual output queue reaching a cache threshold; the first flow control protocol message is provided with a first indication Virtual Local Area Network (VLAN) identifier of the first virtual port;

sending the first flow control protocol message to a first line card board where a first expansion port corresponding to the first virtual port is located; and the first line card board sends the first flow control protocol message with the first indication virtual local area network VLAN identification stripped through the first expansion port corresponding to the first indication virtual local area network identification.

2. The method of claim 1, wherein before counting the number of buffered data packets per virtual output queue, the method further comprises:

allocating a virtual port and an indication VLAN of each expansion port;

allocating a virtual output queue and a port scheduler for each virtual port;

setting a buffer quantity counter of each virtual output queue to count the number of buffer data messages of each virtual output queue;

and informing the indication VLAN of each expansion port to the line card board where each expansion port is positioned.

3. The method of claim 2, further comprising:

receiving a second flow control protocol message with a second indication VLAN through a second line card board;

and opening or closing a port scheduler of a second virtual port corresponding to a second indication VLAN according to the second flow control protocol message.

4. The method according to claim 1, wherein the first traffic control protocol packet generated for the first virtual port corresponding to the virtual output queue reaching the buffering threshold further carries first traffic priority information; the method further comprises:

sending the first flow control protocol message to a first line card board where a first expansion port corresponding to the first virtual port is located; and the first line card board transmits a first flow control protocol message with the first indication virtual local area network VLAN identifier stripped through the first expansion port corresponding to the first indication virtual local area network identifier to suppress the data message corresponding to the first service priority information.

5. The method of claim 4, wherein before counting the number of buffered data packets per virtual output queue, the method further comprises:

allocating a virtual port of each expansion port and indicating a VLAN;

a port scheduler that allocates each virtual port;

distributing each virtual port and each virtual output queue of the service priority and a queue scheduler;

and informing the indication VLAN allocated to each expansion port to the line card board where each expansion port is located.

6. The method of claim 5, further comprising:

receiving a second flow control protocol message with a second indication VLAN and second service priority information through a second line card board;

and opening or closing a second virtual port corresponding to a second indication VLAN and a queue scheduler of second service priority information according to the second flow control protocol message.

7. The flow control equipment is characterized by at least comprising a statistical module, a storage module, a flow control module and a sending module;

a plurality of buffer number counters of the statistical module respectively correspond to the virtual output queues of the storage module; the plurality of buffer quantity counters are used for counting the number of the buffer data messages of each corresponding virtual output queue;

the flow control module is used for generating a first flow control protocol message for a first virtual port corresponding to the virtual output queue reaching the cache threshold value; the first flow control protocol message carries a first indication Virtual Local Area Network (VLAN) identifier of the first virtual port;

the sending module is configured to send the first traffic control protocol packet to the first line card where the first expansion port corresponding to the first virtual port is located.

8. The apparatus of claim 7, further comprising:

the setting module is used for distributing the virtual ports of the expansion ports and indicating the VLAN; allocating a virtual output queue and a port scheduler of each virtual port; setting the plurality of buffer quantity counters corresponding to the virtual output queues;

and the notification module is used for notifying the indication VLAN of each expansion port to the line card board where each expansion port is located.

9. The apparatus of claim 8,

the receiving module is used for receiving a second flow control protocol message with a second indication VLAN through a second line card board;

and the flow control module opens or closes a port scheduler of a second virtual port corresponding to a second indication VLAN according to the second flow control protocol message.

10. The apparatus of claim 7,

the flow control module is further configured to generate the first flow control protocol packet and first service priority information for the first virtual port corresponding to the virtual output queue that reaches the cache threshold;

the sending module is further configured to send the first traffic control protocol packet with the first indication virtual local area network VLAN identifier and the first service priority information to the first line card where the first expansion port corresponding to the first virtual port is located.

11. The apparatus of claim 10,

a setting module, configured to allocate a virtual port of each expansion port to indicate a VLAN; a port scheduler that allocates each virtual port; distributing each virtual port and each virtual output queue of service priority and a queue scheduler; setting the plurality of buffer quantity counters corresponding to the virtual output queues;

the notifying module is further configured to notify the indication VLAN of each expansion port to the line card board where each expansion port is located.

12. The apparatus of claim 11,

the receiving module is further configured to receive, through the second line card, a second traffic control protocol packet with a second indication VLAN and second service priority information;

the flow control module is further configured to open or close a second virtual port corresponding to a second indication VLAN and a queue scheduler of second service priority information according to the second flow control protocol packet.