RU2427091C2 - Device and method for speed limit-based flow control for mstp device - Google Patents

Abstract

FIELD: information technology.

SUBSTANCE: when data flow exceeds a traffic control threshold, a traffic control signal is sent a remote device directing the remote device to reduce flow of input data, which enables to avoid packet loss due to speed limit in the disclosed device. By controlling flow of output data by marking the service stream, flow can be controlled for the Ethernet level 2 frame port pause and flow can be controlled for a specific service at Ethernet level 3 and malfunction of the service due to overflow of the output queue can be prevented. The invention can also guarantee uninterrupted flow of data of packet services, enables to determine throughput needed for the service, and the corresponding alerting, and meets flow control requirements for the specific service when the Ethernet service is transported in an MSTP transmission device.

EFFECT: guaranteeing integrity of the control module.

12 cl, 4 dwg

Description

Technical field

The present invention relates to transport devices of a multi-service transport platform (MSTP, Multi-Service Transport Platform) in a communication system, and more particularly, to a device and method for controlling traffic based on speed limitation in an MSTP transport device.

State of the art

Traffic management is a typical function in a data network in a communication system. The MSTP device supports access for Ethernet, ATM data transfer services (ATM, Asynchronous Transfer Mode, etc.). For Ethernet applications, the MSTP device can limit the input data rate, and when the Ethernet data flowing to the MSTP device exceeds the agreed speed, service data that exceeds the bandwidth will be discarded, or traffic control will be implemented by sending a frame to the remote device Layer 2 PAUSE control to avoid overflowing the output queue in the direction of transferring Ethernet data coming into the MSTP device due to improper scheduling. Thus, for data flow in the MSTP device, there is traffic control at the input and control of the output queue.

When using the known method of traffic control based on the FIFO buffer (“first come, first served”) or the queue, traffic control through FIFO supports an uninterrupted service process, in which, in the general case, a traffic control frame is sent to the source port (input port of the data stream), when the MAC level FIFO buffer (media access control layer) is almost full or the output queue is almost full. In known technical solutions, the control of the input traffic can be turned on or off, that is, the speed control at the input to limit the speed may or may not take place. When there is no speed control, only bandwidth can be controlled: packets for which the required data throughput exceeds a threshold value will be discarded, which will disrupt services. In addition, the traffic control mechanism is completely isolated from speed limits, and they are not related to each other. That is, since the speed control is carried out at the input, the data transfer of services may be disrupted, since packet loss due to the speed limit is not related to the launch of the traffic control frame.

The method of limiting the input speed used in known technical solutions may disrupt the transmission of data services and, thus, cannot guarantee the integrity of these services.

SUMMARY OF THE INVENTION

The present invention provides a device and method for controlling traffic based on a rate limitation in an MSTP device in order to solve a problem inherent in the known technical solution in which packets can be dropped when the input data bandwidth exceeds a threshold value and service data transmission may be interrupted. since the speed limit is not related to the traffic control frame; Thus, the proposed solution allows for traffic management, which guarantees accurate and complete data transfer services.

The present invention provides a rate limiting traffic control apparatus for an MSTP device. The device includes a data input module, a classification module, a control module, a scheduling / queue management module and a data output module that are connected one after another, as well as an administration module that is connected to and controls all of the above-mentioned modules, while:

a data input module is used to receive an input data stream;

the classification module is used to assign a stream label to the input data stream according to the classification rule and to determine the corresponding output queue, transmitting the stream label to the administration module and transmitting the data stream with the label to the control module;

the administration module is used to set management parameters, which include a speed limit threshold for speed control and a traffic control threshold for traffic control;

the control module serves to control the traffic of the received data stream according to the flow label transmitted by the classification module and the agreed control parameters for the flow label transmitted by the administration module; and when the input data stream traffic exceeds the traffic control threshold, transmitting a traffic control frame to the remote device node instructing to reduce the input data stream traffic, and when the output data stream traffic exceeds the speed limit threshold, discarding the corresponding packet or marking this packet as invalid data, and outputting the data stream to the planning / queue management module;

the scheduling / queue management module serves to manage the received data and scheduling the received data, discarding the packet marked as invalid data, placing the packet marked as normal data in the queue, processing the packet marked as normal data, and then transmitting the processed packet to the corresponding output port for transmission;

the data output module serves to output the normal data stream according to the processing result in the planning / queue management module.

The specified device further comprises:

EOS encapsulation and processing module (Ethernet over SDH, Ethernet over SDH (SDH - Synchronous Digital Hierarchy)), which is associated with the specified scheduling / queue management module and is used to determine the status of the SDH channel and provide real-time information about the SDH channel throughput virtual concatenation group (VCG, Virtual Concatenation Group) in the administration module, when the number of the VCG group member changes;

a traffic control triggering module associated with said monitoring module and triggering the transmission of the corresponding traffic control frame according to the result of monitoring the flow label of a particular service by the monitoring module; and

MAC control module that controls the transmission / reception of a packet over an Ethernet interface.

In addition, the management parameters set by the administration module include:

a speed limit threshold for speed control, including a data transfer speed Vd to start speed control and a packet burst length Ld when the parameters of the single hole bucket algorithm are set, or Vdmax / Ldmax and Vdmin / Ldmin when the parameters of the double hole bucket algorithm are set ";

a traffic control threshold for flow control, including a data transfer speed Vc for triggering traffic control and a packet packet length Lc when the parameters of the “single hole bucket” algorithm are set;

at the same time, the packet lengths for all these packets must meet one condition: the packet packet lengths exceed the maximum packet length allowed for the passage of the data stream.

In addition, the specified control module is configured to:

stopping the transmission of a traffic control frame to the remote device node indicating to reduce the input data stream traffic when the input data stream traffic is less than or equal to the traffic control threshold; and

traffic control of the output data stream when the remote device does not respond to the specified traffic control frame, while:

when the speed limit threshold is configured in the form of parameters (Vd, Ld) of the “single hole bucket” algorithm, the control module discards the corresponding packet or marks this packet with a red mark indicating that the packet is invalid data if the output stream traffic exceeds the threshold Vd limit speeds, and otherwise - marks the packet with a green label indicating that this packet is normal data and outputs the data stream to the planning / queue management module;

when the speed limit threshold is set in the form of the Vdmax / Ldmax and Vdmin / Ldmin parameters of the “double hole bucket” algorithm, then

if the monitored traffic of the service data stream does not violate the agreed lower thresholds (Vdmin, Ldmin), the control module marks the packets with a green label;

if the monitored traffic of the service data stream exceeds the agreed lower thresholds (Vdmin, Ldmin), but does not exceed the agreed upper thresholds (Vdmax, Ldmax), the control module marks the packets with a yellow mark;

if the monitored traffic of the service data stream exceeds the agreed upper thresholds (Vdmax, Ldmax), the control module marks the packets with a red mark or directly drops the packets; and

sends color labels to packets to the scheduling / queue management module.

In addition, in the specified scheduling / queue management module:

There are two kinds of options for controlling removal from the queue:

a lower half-fill threshold Lh and an almost full fill upper threshold Lf;

when processing received packets, received packets marked with a red mark are discarded directly, and those marked with a yellow / green mark are processed according to the queue status as follows:

when the volume of all packets in the queue is less than the lower threshold Lh of the queue, all packets arrive in the queue;

when the volume of all packets in the queue exceeds the lower threshold Lh of the queue, but is smaller than the upper threshold Lf of the queue, packets marked with a green label go into the queue, and those marked with a yellow label are discarded;

when the volume of all packets in the queue exceeds the upper threshold Lf of the queue, all newly received packets are discarded.

In addition, when the throughput of the specified data encapsulation and EOS processing module in the virtual concatenation group (VCG) is less than the traffic control threshold, this information is sent to the administration module, and the administration module modifies the traffic control threshold for the control module according to the VCG practical throughput by making this traffic control threshold less than or equal to VCG practical throughput.

In addition, the present invention provides a traffic control method based on the above device, comprising the following steps:

(1) the classification module assigns the corresponding stream label to the input data stream according to the classification rule, determines the output queue for input packets, and transfers the specified stream label to the administration module;

(2) the administration module sets, according to an agreed rule, control parameters for services corresponding to the specified flow label, wherein control parameters include a traffic control threshold for traffic control and a speed limit threshold for speed limitation;

(3) the control module controls, according to the control parameters agreed upon by the administration module, the data traffic of services carrying the flow label, starts the flow control when the input data stream traffic exceeds the traffic control threshold, and sends a traffic control frame to the remote device node instructing to reduce the flow input data;

(4) if the remote device does not respond to the traffic control frame, the control module controls, according to the control parameters agreed upon by the administration module, the service data carrying the flow label, and if the output data exceeds the speed limit threshold, marks the packets as invalid data, and in otherwise, marks them as normal data and passes the marked packets to the planning / queue management module;

(5) the planning / queue management module manages and scans received data, discards, according to the label information of received packets, packets that are marked as invalid data, puts packets marked as normal data, and in turn processes packets marked as normal data, and after scheduling sends packets marked as normal data to the corresponding output port.

In addition, setting the control parameters in step (2) includes:

setting the speed limit threshold, including the data transfer speed Vd to start the speed control and the packet packet length Ld when setting the parameters of the single hole bucket algorithm or including the values of Vdmax / Ldmax and Vdmin / Ldmin when setting the parameters of the double hole bucket algorithm; and

setting a traffic control threshold for flow control, including a data transfer speed Vc for triggering speed control and a packet packet length Lc when setting parameters of a “single hole bucket” algorithm;

in this case, the packet lengths of all the indicated packets must meet one condition: the packet lengths exceed the maximum packet length allowed for the passage of the data stream.

In addition, step (3) further includes:

traffic control of the input data stream according to the stream label transmitted from the classification module and the agreed control parameters for the stream label transmitted from the administration module:

when the traffic of the input data stream exceeds the traffic control threshold Vc, sending to the remote device a traffic control frame instructing to reduce the input data stream; and

when the input data stream again becomes less than or equal to the traffic control threshold Vc, the transmission of the traffic control frame instructing to reduce the input data stream to the remote device is stopped.

In addition, step (4) further includes:

Monitoring traffic of the output data stream according to the stream label transmitted from the classification module and the agreed control parameters for the stream label transmitted from the administration module, as follows:

when the speed limit threshold is set in the form of parameters (Vd, Ld) of the “single hole bucket” algorithm, if the output stream traffic exceeds the velocity limit threshold Vd, discard the corresponding packets or mark packets with a red mark indicating that these packets are invalid data, and otherwise, packets are marked with a green label indicating that they are normal data and the data stream is output to the scheduling / queue management module;

when the speed limit threshold is set in the form of the Vdmax / Ldmax and Vdmin / Ldmin parameters of the “double hole bucket” algorithm,

if the monitored traffic of the service data stream exceeds the agreed lower threshold parameters (Vdmin, Ldmin), but does not exceed the agreed upper threshold parameters (Vdmax, Ldmax), mark the packets with a yellow mark;

if the monitored traffic of the service data stream exceeds the agreed upper threshold parameters (Vdmax, Ldmax), mark the packets with a red mark or drop them directly; and

transmit color labels of packets to the scheduling / queue management module.

In addition, step (2) further includes a step for setting deletion control parameters from the queue, wherein the set of deletion control parameters from the queue includes a lower half-fill threshold Lh and an almost full fill upper threshold Lf;

accordingly, when the scheduling / queue management module processes the received packets in step (5), the received packets marked with a red mark are discarded directly, and those marked with a yellow / green mark are processed according to the status of the queue as follows:

when the volume of all packets in the queue is less than the lower threshold Lh of the queue, packets are queued;

when the volume of all packets in the queue exceeds the lower threshold Lh of the queue, but less than the upper threshold Lf of the queue, packets marked with a green mark are queued, and those marked with a yellow mark are discarded; and

when the volume of all packets in the queue exceeds the upper threshold Lf of the queue, all packets just received are discarded.

In addition, this method further includes the following steps:

when the data encapsulation and EOS processing module is used as the output module, if the capacity of the virtual concatenation group is less than the traffic control threshold, this is reported to the administration module, and the administration module modifies, according to the practical bandwidth of the virtual concatenation group, the traffic control threshold for control module, making the traffic control threshold less than or equal to the practical bandwidth of the virtual concatenation group.

The application of the technical scheme according to the present invention can provide flow traffic control at a given throughput as follows: when the data flow exceeds the traffic control threshold, a traffic control signal is sent to the remote device, which reduces the data flow after receiving the traffic control frame, thus preventing The packet was dropped due to speed limits on the device. Through the marking function of the service flow, traffic control can be carried out for the Ethernet layer 2 pause frame port and for specific Level 3 services, preventing service disruption due to overflow of the output queue.

The present invention optimizes the traffic control strategy in the MSTP transport network, can guarantee the transmission of an unbroken data stream of services based on the packetized data stream in the network, and provides a determination of the throughput for the services and corresponding notification, providing convenience for operators when manipulating the operating modes of services in the network, thus improving the strategy of traffic management in the urban network and meeting the requirements of the Ethernet service for traffic control of specific services in the transport device The MSTP. The present invention allows to reduce resource loading by abnormal services, to avoid disruption of services and to improve the quality of transmission in the network through the mechanism of traffic control and bandwidth.

Brief Description of the Drawings

1 shows a functional block diagram of an MSTP device according to one embodiment of the present invention.

FIG. 2 illustrates a traffic control process by a speed limiting traffic control apparatus according to an embodiment of the present invention.

FIG. 3 shows a traffic control flowchart according to an embodiment of the present invention.

4 shows a flowchart of processing speed parameters for adjusting traffic control according to an embodiment of the present invention.

Preferred Embodiments of the Present Invention

The following describes the implementation of the technical principles of the present invention with the accompanying drawings and embodiments of the present invention.

In this embodiment of the present invention, the main concept of traffic control based on speed limitation is as follows.

On the receiving side of the MSTP device, if the received data stream detected by the monitoring module exceeds the agreed bandwidth, this module notifies the remote device of the need to reduce the data stream sent to the MSTP device by feedback using the traffic control frame sent to the remote device (not discarding services in excess of bandwidth), to control bandwidth with respect to port or stream-based service data, to avoid disruption of transport with uzhby.

In addition, in the direction from the Ethernet network to the Synchronous Digital Hierarchy (SDH) network, if the service channel bandwidth in the direction of the Ethernet over SDH (EOS, Ethernet over SDH) encapsulation and processing module of the MSTP decreases for communication line abnormalities, the device control module adjusts the bandwidth parameters for traffic control of the input stream of the Ethernet service corresponding to this communication line, and when it detects that the bandwidth of the input service data stream exceeds the predetermined output traffic control bandwidth parameters, it controls the service data bandwidth. In this case, a report on changes in the practical throughput of the communication line can be received through the control interface in real time.

This embodiment of the present invention provides a traffic control device based on a rate limitation in an MSTP device. Figure 1 shows a functional block diagram of a device that contains the following main parts: data input module, classification module, control module, planning / queue management module, data output module and administration module, wherein:

1) the data input module includes a MAC and EOS processing module, that is, it is a data input interface. It is used to receive a service data stream transmitted from an external device and transmit a service data stream to a classification module;

2) the classification module is used to assign a stream label and organize an output queue for a service data stream transmitted from an external device, according to an agreed rule.

In the classification module, input service packets are classified in accordance with an agreed rule (classification rule) for classifying and identifying the service data stream, and those packets that obey the rule are marked with the corresponding flow label, which is transmitted to the administration module. The process taking place in the classification module also includes determining the target queue of the output packets.

An agreed rule is a classification rule; for an Ethernet service, it can, but is not limited to, include the following: port / port + VLAN / port + VLAN + DSCP / port + VLAN + 802.1P,

which is used to distinguish subscriber service flows (a way to define a service flow is to generate a flow label according to the above information). The above agreed rule is a known technical solution.

3) The administration module is used to offer a configuration management interface that organizes and manages the data input / output module, classification module, control module, Queue planning / management module, and manages and issues an information report on the data flow and queue parameters according to the flow label for the service data stream, for example, monitoring the VCG bandwidth and configuring the control module control parameters, including the traffic control threshold, assigned to control traffic, and a speed limit threshold designed to limit speed.

In accordance with the agreed rule, the administration module sets the agreed control parameters for the service data stream corresponding to the stream label, including data transmission speed V and packet packet length L.

One type of parameter is the data rate Vd for triggering the speed control and the length Ld of the packet burst, that is, the rate limiting threshold for speed limiting.

Another type of parameter is the data rate Vc for triggering the rate control and the packet length Lc, that is, a traffic control threshold for managing traffic.

In any parameter configuration mode, the length L of the packet packet must meet one condition: it exceeds the maximum packet length allowed for the passage of the data stream.

4) The control module is used to control the bandwidth for the service according to the control parameters (mainly speed parameters) generated by the administration module, and to control the speed or to send a traffic control frame according to the parameters of the service flow.

When the control module receives packets, it controls the data stream according to the identifier (ID) of the data stream label transmitted from the classification module and the agreed control parameters for the stream label transmitted from the administration module, and performs the corresponding process according to the traffic control result (determines if it is violated rule or not).

When the traffic of the service data input stream exceeds the generated traffic control threshold, this module sends a traffic control frame to the service data source node, instructing it to reduce the input data rate to reduce the input stream;

When the traffic output stream of the service data exceeds the generated rate limit threshold, data that does not meet the rule is discarded or marked, and marked packets are sent to the scheduling / queue management module.

5) According to the flow label, the queuing / scheduling module is used to assign a queue for received packets according to the output port and packet priority, performs queue management and scheduling, and transfers the packets to the corresponding output port. In this case, after the specified planning / queue management module receives packets, it places the input packets in the queue or discards them according to the packet labeling information, as well as the conditions for using the resource in the target queue corresponding to the packets. At the same time, it schedules packets in a queue and sends packets to the corresponding output port (Ethernet port or EOS port).

6) The data output module contains a MAC control module, an EOS module, etc. and is used to send packets to the appropriate port.

Figure 2 shows a device for controlling traffic based on a speed limit, which, according to this Embodiment of the present invention, may comprise:

EOS data encapsulation and processing module, which is used to detect the status of the SDH channel and transmit real-time information about the bandwidth of the SDH channel of the VCG group to the administration module when the number of members in the VCG group changes;

a traffic control frame trigger module that is used to trigger a corresponding traffic control frame according to a result of detecting a particular service flow label by the monitoring module;

MAC control module, which is used to receive and transmit control data via Ethernet.

Figure 2 illustrates the traffic control process for the input data stream according to the configuration based on the combination of modules shown in figure 1, in order to control the speed and traffic of the input data in one Ethernet port, while data output occurs through the VCG port.

If you need service data accessed via the Ethernet port, the allowed guaranteed bandwidth for the service is 30 M, peak bandwidth is 35 M, VCG bandwidth is 30 M, the GFP encapsulation protocol is used at the VCG output, and virtual concatenation supports the protocol LCAS. The following steps take place:

A. According to the service configuration, the classification module assigns a flow label and assigns an output queue for data received on the Ethernet port, the administration module configures the agreed control parameters, which are used to control the speed / limit of the flow rate with the flow label ID, VCG members and operation mode .

A1. The management parameters agreed upon by the administration module include the agreed data transmission rate V and the agreed packet packet length L, and in this embodiment of the present invention they correspond to two kinds of control parameters:

control parameters for traffic control used to start the traffic control frame in order to limit the required input bandwidth;

control parameters for speed limitation, used to limit the required throughput when transmitting in the output direction.

For control parameters intended for speed control, depending on the type of service, you can select the control parameters of the “single hole bucket” or “double hole bucket” algorithm. The parameters of the single hole bucket algorithm are Vd / Ld, and the parameters of the double hole bucket algorithm are the maximum values of Vdmax / Ldmax and the minimum values of Vdmin / Ldmin. At the same time, the controlled throughput corresponding to Vdmax and Ldmax is relatively large and corresponds to the throughput for packets with upper threshold parameters; the controlled throughput corresponding to Vdmin and Ldmin is relatively small and corresponds to the guaranteed throughput for lower threshold parameters. In this embodiment of the present invention, Vdmax = 35 M and Vdmin = 30 M. In the output process, control parameters for speed control can be used to control the output stream and apply appropriate invalid data processing according to the result of the traffic control.

For control parameters for traffic control, the Vc / Lc parameters of the “single hole bucket” algorithm are used, and they are formed by comparing with lower threshold parameters (guaranteed throughput), for which the controlled throughput in the control parameters for speed control is relatively small. The method of forming parameters is as follows:

a) the data transfer rate for starting the speed control is equal to the speed for starting the traffic control (Vd = Vc), while the packet packet for starting the speed control exceeds the length for starting the traffic control (Ld> = Lc), which can be implemented as: Vd = Vc = 30 M, Ld = Lc = 64 kB;

b) the data transfer rate for starting the speed control exceeds the speed for starting the traffic control (Vd> Vc), and the length of the packet packet for starting the speed control is equal to the length of the traffic control start (Ld = Lc), which can be implemented as: Vd = 30 M and Vc = 29 M, Ld = Lc = 64 kB;

c) the data transfer rate for starting the speed control exceeds the speed for starting the traffic control (Vd> Vc), and the packet packet length for starting the speed control exceeds the length for starting the traffic control (Ld> Lc), which can be implemented as: Vd = Vc = 30 M, Ld = Lc = 64 kB, Ld = 64 kB / 1 s = 60 kB.

A2. The classification module assigns an output queue for the service corresponding to the stream label ID, the queue corresponds to the VCG output port. Queues at VCG ports can be organized using different priorities. There are two types of queue removal control parameters: the lower half-fill threshold Lh and the almost full fill upper threshold Lf. When the volume of packets in the queue exceeds the corresponding volume, for the new input packets, the corresponding operation is performed according to the color mark, and this corresponding operation is illustrated in C2.

B. As shown in FIG. 3, the monitoring module monitors the traffic of the service data for the identifier of the stream label (including the control of the input data stream and the output data stream) according to the “leaky bucket” algorithm and performs the corresponding operations according to the result of such monitoring.

IN 1. When these services do not match the control parameters (Vc, Lc) for traffic control, the traffic control starts. In this case, the notification of the remote device occurs, instructing it to reduce the flow of incoming data by sending a PAUSE traffic control frame (PAUSE) to the remote device connected to the device in question in the Ethernet port in full duplex mode; if the data stream for the monitored service with the stream label identifier does not violate the agreed control parameters (Vc, Lc), it stops sending the PAUSE traffic control frame.

Here, the term “does not violate” means that the practical data rate does not exceed the data rate Vc specified in the control parameters. Using the traffic control frame processing mechanism, it is possible to efficiently manage practical traffic / required throughput of received service data. A reasonable time to send the PAUSE traffic control frame can be ensured by the fact that the traffic control frame enters the queue for transmission with the highest priority. The content of the PAUSE traffic control frame complies with standard technical solutions. The traffic control frame contains timestamp information that determines when the remote device should stop sending a data frame after receiving this PAUSE frame. The timestamp value in the PAUSE frame sent by the device is 0, which means that the traffic control ends at that moment.

B2. If the remote device does not respond to the traffic control frame sent by the device, the data flow received by this device may gradually increase, and in this case the output bandwidth limit for the monitoring module starts to operate, ensuring the device and the network work properly, this process is shown in B3.

IN 3. The control module monitors the data stream of the identifier of the stream label according to the parameters (Vd, Ld) of the speed limit;

when the monitored traffic of service data does not go beyond the lower threshold parameters (Vdmin, Ldmin), marks packets with a green label;

when the monitored service data traffic exceeds the agreed lower threshold parameters (Vdmin, Ldmin), but does not exceed the agreed upper threshold parameters (Vdmax, Ldmax), marks the packets with a yellow label;

when the service data traffic exceeds the upper threshold parameters (Vdmax, Ldmax), marks packets with a red mark or directly discards them;

sends packet color labels to the scheduling / queue management module.

C. When the scheduling / queue management module receives a packet, it makes a decision whether to queue packets or not, depending on the amount of packets waiting to be scheduled in the target queue at the VCG port, the color label of the packets just received, and their length.

C1. It directly discards received packets that have a red mark.

C2. It processes the received packets marked in yellow / green as follows depending on the status of the queue:

if the volume of all packets in the queue is less than the lower threshold Lh for the queue, queues the packets;

if the volume of all packets in the queue exceeds the lower threshold Lh for the queue, but is less than the upper threshold Lf for the queue, queues the packets marked with a green label and discards those marked with a yellow label;

if the volume of all packets in the queue exceeds the upper threshold Lf for the queue, discards all new received packets.

D. The scheduling / queue management module scheduling according to the port's throughput and transfers packets in the queue at the port to the output port and transmits them from the device. Output ports include a VCG port and an Ethernet port, and data transmitted from a VCG port is encapsulated using the GFP protocol in the EOS module and output from the device via the SDH interface.

In this embodiment of the present invention, throughput without interruption in service is controlled by two-stage traffic control:

The first stage: control and processing of the start of traffic control affect only the processing of the PAUSE frame;

Second stage: only control and processing of the speed limit can lead to packet loss.

It is because of this that you can guarantee uninterrupted service when the controlled bandwidth for starting traffic control is less than the bandwidth for speed limitation: when the remote device receives the PAUSE frame, while not reducing the packet sending speed, if the rate limiting mechanism for the second stage detects that the service is illegal, it drops the packet, that is, the packet is lost.

The above embodiment of the present invention, illustrated in FIG. 2 and FIG. 3, shows a traffic control method based on a Rate limitation. Figure 4 shows an advanced version of traffic control. The following describes the operation method of the VCG output port, in which virtual concatenation supports traffic control within the framework of the LCAS protocol when the throughput changes, and the following sequence of operations is presented to understand the process described in Fig. 4:

4.1. When the EOS processing module supports the LCAS protocol, the number of VCG group members is dynamically increasing or decreasing, and the VCG bandwidth is changing as part of the VC channel is broken. When the VCG throughput is less than the speed threshold Vc in the control parameters for traffic control, the control parameters (Vd, Ld) for speed limiting cannot effectively control the data transfer rate, and there are losses due to scheduling congestion in the output port queue. Therefore, when the throughput offered by the VCG is less than Vc, the administration module modifies the control parameters used by the flow label identifier in the control module according to the practically available throughput of the VCG: modifies the Vc, making this parameter less than or equal to the practical throughput of the VCG, at this leaving Lc unchanged.

4.2. The traffic control process for the control module is the same as the sequence of operations during normal processing: the control of the input data of the stream label ID service and the formation of the traffic control frame are started when the service data stream does not satisfy the new control parameters (Vc, Lc) for traffic control ; the process of generating control parameters for controlling the speed is compatible with a conventional processing process.

The method of dynamically adjusting control parameters for controlling traffic of a data stream according to VCG bandwidth can effectively reduce the probability of loss of service data packets when the VCG bandwidth is less than the default configuration, and thus avoiding service outages in the transmission path.

In the embodiment of the present invention shown in FIG. 2, FIG. 3 and FIG. 4, the administration module can report a change in throughput for a service through a software interface, thereby providing real-time throughput information for the access service and improving the function service management in the MSTP device.

Industrial application

The present invention discloses a device and method for controlling traffic based on speed limitation in an MSTP device in a communication system for controlling traffic based on speed limitation, thereby ensuring uninterrupted transmission of packetized service data flow in the network and determining the throughput for services and transmitting the corresponding report in order to reduce resource loading by abnormal services, prevent service disruption and improve the quality of transmission in the network.

Claims (12)

1. A device for controlling traffic by limiting the speed in the device multiservice transport platform, containing:
a data input module, a classification module, a control module, a planning / queue management module and a data output module, connected one after another, as well as
an administration module that is connected to and controls all of the above-mentioned modules, while
a data input module is used to receive an input data stream;
the classification module is used to assign a stream label to the input data stream according to the classification rule, to determine the corresponding output queue, to transfer the stream label to the administration module and to transfer the data stream with the label to the control module;
the administration module is used to set control parameters, which include a speed limit threshold for speed control and a traffic control threshold for traffic control based on the specified stream labels transmitted from the classification module;
the control module serves to control the traffic of the received data stream according to the flow label transmitted by the classification module and the control parameters for the flow label transmitted by the administration module; and when the input data stream traffic exceeds the traffic control threshold, transmitting a traffic control frame to the remote device node instructing to reduce the input data stream traffic, and when the output data stream traffic exceeds the speed limit threshold, discarding the corresponding packet or marking this packet as invalid data and outputting the data stream to the planning / queue management module;
the scheduling / queue management module is used to manage the received data and scheduling the received data, discarding the packet marked as invalid data, placing the packet marked as normal data in the queue, processing the packet marked as normal data, and then transmitting the processed packet to the corresponding output port for transmission;
the data output module serves to output the normal data stream according to the processing result in the planning / queue management module. 2. The device according to claim 1, which further comprises:
EOS (Ethernet over Synchronous Digital Hierarchy, Ethernet over Synchronous Digital Hierarchy) data encapsulation and processing module, associated with the specified planning / queue management module, designed to determine the channel status of the synchronous digital hierarchy and to provide real-time information about the channel bandwidth of the synchronous digital hierarchy for a virtual concatenation group to the administration module, when the member number of the virtual concatenation group changes;
a traffic control triggering module associated with said monitoring module and triggering the transmission of the corresponding traffic control frame according to the result of monitoring the flow label of a particular service by the monitoring module; and
a media access control layer control module that manages packet reception / transmission over the Ethernet interface. 3. The device according to claim 1, in which the control parameters set by the administration module include:
a speed limit threshold for speed control, including a data transfer speed Vd to start speed control and a packet burst length Ld when the parameters of the single hole bucket algorithm are set, or Vdmax / Ldmax and Vdmin / Ldmin when the parameters of the double hole bucket algorithm are set ";
a traffic control threshold for flow control, including a data transfer speed Vc for triggering traffic control and a packet packet length Lc when the parameters of the “single hole bucket” algorithm are set;
at the same time, the packet lengths for all of the indicated packets must meet one condition: the packet packet lengths exceed the maximum packet length allowed for the data flow. 4. The device according to claim 3, in which the specified control module is configured to:
stopping the transmission of a traffic control frame to the remote device node indicating to reduce the input data stream traffic when the input data stream traffic is less than or equal to the traffic control threshold; and
control the traffic of the output data stream when the remote device does not respond to the specified traffic control frame, while
when the speed limit threshold is configured in the form of parameters (Vd, Ld) of the “single hole bucket” algorithm, the control module discards the corresponding packet or marks this packet with a red mark indicating that the packet is invalid data if the output stream traffic exceeds the threshold Vd limit speeds, and otherwise - marks the packet with a green label indicating that this packet is normal data and outputs the data stream to the planning / queue management module;
when the speed limit threshold is set in the form of the Vdmax / Ldmax and Vdmin / Ldmin parameters of the “double hole bucket” algorithm, then
if the monitored traffic of the service data stream does not violate the agreed lower thresholds (Vdmin, Ldmin), the control module marks the packets with a green label;
if the monitored traffic of the service data stream exceeds the agreed lower thresholds (Vdmin, Ldmin), but does not exceed the agreed upper thresholds (Vdmax, Ldmax), the control module marks the packets with a yellow mark;
if the monitored traffic of the service data stream exceeds the agreed upper thresholds (Vdmax, Ldmax), the control module marks the packets with a red mark or directly drops the packets; and
sends color labels to packets to the scheduling / queue management module. 5. The device according to claim 4, in which in the specified module planning / queue management:
There are two kinds of options for controlling removal from the queue:
a lower half-fill threshold Lh and an almost full fill upper threshold Lf;
when processing received packets, received packets marked with a red mark are discarded directly, and those marked with a yellow / green mark are processed according to the queue status as follows:
when the volume of all packets in the queue is less than the lower threshold Lh of the queue, all packets arrive in the queue;
when the volume of all packets in the queue exceeds the lower threshold Lh of the queue, but is smaller than the upper threshold Lf of the queue, packets marked with a green label go into the queue, and those marked with a yellow label are discarded;
when the volume of all packets in the queue exceeds the upper threshold Lf of the queue, all newly received packets are discarded. 6. The device according to claim 2, in which, when the throughput of the specified data encapsulation and EOS processing module in the virtual concatenation group is less than the traffic control threshold, this information is sent to the administration module, and the administration module modifies the traffic control threshold for the control module according to the practical bandwidth of the virtual concatenation group, making this traffic control threshold less than or equal to the practical bandwidth of the virtual concatenation group. 7. The method of traffic control based on the device according to claim 1, comprising the following steps:
(1) assign the appropriate stream label to the input data stream according to the classification rule, determine the output queue for input packets and transmit the specified stream label to the administration module;
(2) establish, according to an agreed rule, control parameters for services corresponding to the specified flow labels transmitted from the classification module, the control parameters including a traffic control threshold for traffic control and a speed limit threshold for speed limitation;
(3) control, according to the control parameters agreed upon by the administration module, the data traffic of services carrying the flow label, start the flow control when the input data stream traffic exceeds the traffic control threshold, and transmit a traffic control frame to the remote device node instructing to reduce the input data stream ;
(4) if the remote device does not respond to the traffic control frame, control, according to the control parameters agreed upon by the administration module, the service data carrying the flow label, and if the output data speed exceeds the speed limit threshold, mark the packets as invalid data, otherwise mark them as normal data and transfer the marked packets to the planning / queue management module;
(5) manage the received data and plan it, discard, according to the label information of the received packets, those packets that are marked as invalid data, put the packets marked as normal data, in turn process the packets marked as normal data, and after planning transmit packets marked as normal data to the corresponding output port. 8. The method according to claim 7, in which setting the control parameters in step (2) includes:
setting the speed limit threshold, including the data transfer speed Vd to start the speed control and the packet packet length Ld when setting the parameters of the single hole bucket algorithm or including the values of Vdmax / Ldmax and Vdmin / Ldmin when setting the parameters of the double hole bucket algorithm; and
setting a traffic control threshold for flow control, including a data transfer speed Vc to start speed control and a packet packet length Lc when setting parameters of a “single hole bucket” algorithm;
in this case, the packet lengths of all the indicated packets must meet one condition: the packet lengths exceed the maximum packet length allowed for the passage of the data stream. 9. The method of claim 8, in which step (3) further includes:
traffic control of the input data stream according to the stream label transmitted from the classification module and the agreed control parameters for the stream label transmitted from the administration module:
when the input data stream traffic exceeds the traffic control threshold Vc, sending a frame to the traffic control unit to the remote device instructing to reduce the input data stream; and
when the input data stream again becomes less than or equal to the traffic control threshold Vc, the transmission of the traffic control frame instructing to reduce the input data stream to the remote device is stopped. 10. The method according to claim 8 or 9, in which step (4) further includes:
monitoring the traffic of the output data stream according to the stream label transmitted from the classification module and the control parameters for the stream label transmitted from the administration module, as follows:
when the speed limit threshold is set in the form of parameters (Vd, Ld) of the “single hole bucket” algorithm, if the output stream traffic exceeds the velocity limit threshold Vd, discard the corresponding packets or mark packets with a red mark indicating that these packets are invalid data, and otherwise, packets are marked with a green label indicating that they are normal data and the data stream is output to the scheduling / queue management module;
when the speed limit threshold is set in the form of the Vdmax / Ldmax and Vdmin / Ldmin parameters of the “double hole bucket” algorithm,
if the monitored traffic of the service data stream exceeds the agreed lower threshold parameters (Vdmin, Ldmin), but does not exceed the agreed upper threshold parameters (Vdmax, Ldmax), mark the packets with a yellow mark;
if the monitored traffic of the service data stream exceeds the agreed upper threshold parameters (Vdmax, Ldmax), mark the packets with a red mark or drop them directly; and
transmit color labels of packets to the scheduling / queue management module. 11. The method according to claim 10, in which step (2) further includes a step of setting deletion control parameters from the queue, wherein the set of deletion control parameters from the queue includes a lower half-fill threshold Lh and an almost full fill upper threshold Lf;
accordingly, when the scheduling / queue management module processes the received packets in step (5), the received packets marked with a red mark are discarded directly, and those marked with a yellow / green mark are processed according to the status of the queue as follows:
when the volume of all packets in the queue is less than the lower threshold Lh of the queue, packets are queued;
when the volume of all packets in the queue exceeds the lower threshold Lh of the queue, but less than the upper threshold Lf of the queue, packets marked with a green label are queued, and those marked with a yellow label are discarded; and
when the volume of all packets in the queue exceeds the upper threshold Lf of the queue, all packets just received are discarded. 12. The method according to claim 7, further comprising the following steps:
when the data encapsulation and EOS processing module is used as the output module, if the capacity of the virtual concatenation group is less than the traffic control threshold, this is reported to the administration module, and the administration module modifies, according to the practical bandwidth of the virtual concatenation group, the traffic control threshold for control module, making the traffic control threshold less than or equal to the practical bandwidth of the virtual concatenation group.

Images