WO2007118396A1

WO2007118396A1 - A method and system for network performance measurement

Info

Publication number: WO2007118396A1
Application number: PCT/CN2007/000503
Authority: WO
Inventors: Daoyan Yang
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2006-04-14
Filing date: 2007-02-13
Publication date: 2007-10-25
Also published as: CN101056215A; CN101056215B

Abstract

A method for network performance measurement, includes the steps of: distributing the flow identification for the measured flow according to the network performance measurement request, configuring the flow identification and the description of the measured flow to the measurement point; the measurement point extracting the packet of the measured flow according to the description of measured flow, generating packet abstract data including the flow identification and the packet identification and reporting it; and calculating the network performance index according to the packet abstract data. The present invention also includes a system for network performance measurement.

Description

Network performance measurement method and system

Technical field

The present invention relates to measurement techniques in the field of communications, and more particularly to methods and systems for measuring network performance. Background technique

With the rapid development of Internet technologies and network services, users' demand for network resources has grown at an unprecedented rate, and the network has become more and more complex. Increasing network users and applications result in heavy network burdens and overloaded network devices, causing network performance degradation. This requires the extraction and analysis of network performance indicators to improve and improve network performance, so network performance measurement has emerged. Through measurement, network bottlenecks can be discovered, network configuration can be optimized, and potential risks in the network can be further discovered, network performance management can be performed more effectively, and network service quality verification and control can be provided. Quantifying, comparing, and verifying service provider quality of service metrics is the primary goal of network performance measurement.

There are two main types of IP network performance measurement methods: active measurement and passive measurement. Active measurement is the use of measurement tools to actively generate measurement traffic at selected measurement points, inject into the network, and analyze the performance of the network based on the measurement data flow. Passive measurement refers to the measurement of the network using measurement equipment on links or devices (such as routers, switches, etc.) without the need to generate excess traffic.

Network performance measurements are divided into directions and can be divided into one-way network performance measurement and round-trip network performance measurement. Unidirectional network performance measurement is a measure of network performance in one direction from one measurement point A to another. The round-trip network performance measurement measures network performance indicators from one measurement point A to another measurement point B and back to measurement point A. For the communication between two points, the QoS may be different in both directions of the round-trip, or the QoS of the same path to and from the two directions is different, so the one-way network performance is not equal to the round-trip delay of the single ticket. Divide by two. Unless otherwise specified in the present invention, network performance measurements are all one-way network performance measurements.

As shown in FIG. 1, the passive measurement system generally includes a measurement controller, a collector, and a measurement device (or a measurement point). The function of the measurement controller is as follows: 1. Configure the measurement points, including: The quintuple of the measured flow, the duration of the measurement. If you use sampling, you also need to configure the sampling algorithm for the measurement points.

■ 2. Receive the network performance indicators reported by the collector and the performance indicators of the text network to the measurement controller of the user or other carrier network.

3. Send measurement requests to the measurement controllers of other carrier networks.

The function of the measuring device is as follows:

1. Extract all or part of the packets belonging to the measured stream according to the configuration of the measurement controller (if the sampling method is used to reduce the number of extracted packets, the measurement points only extract a part of the packets of the measured stream according to the sampling algorithm).

2. Clock synchronization. Performing a one-way performance measurement requires that the measurement points must be clock synchronized.

' 3. If sampling is used, a part of the message of the measured stream is extracted according to the algorithm.

4. Attach a timestamp information to the extracted target message.

5. Generate message digest data according to the extracted packet, and at least the message digest data includes: - a stream identifier, which is used to uniquely identify the stream to be measured. After the packet digest data of different measurement points is aggregated to the collector, the number of packet digests extracted from different measurement points is matched according to the flow identifier to determine the same measured stream collected by different measurement points.

- Message identification, which is used to uniquely identify the essays belonging to the same measured stream. After the summary data of the 艮汇汇汇汇汇汇 , 摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要摘要_ text.

- Timestamp, used to measure point delay. The delay between two measurement points is determined according to the timestamp information in the message summary data of different measurement points.

The functions of the collector are as follows:

1. Store the message summary data sent from the measurement point.

2. Calculate the delay of each packet and whether it is lost according to the packet summary data of different measurement points. (If the upstream measurement point extracts the message and does not extract it at the downstream measurement point, then it is judged that the message is in the transmission process. Lost in it).

' 3, according to the delay and loss of each ^ ^ 艮 text, can be calculated within a period of time (this The time period is called the calculation interval (Evaluation lnterval), and the network performance indicators such as average delay, maximum delay, delay, delay jitter, packet loss rate, and network unavailability.

4. Report the performance indicators to the measurement controller.

In the prior art, the flow identifier is generally obtained from the extracted packet header, and the flow identifier may be a quintuple, that is, composed of a source IP address, a destination IP address, a source port number, a destination port number, and a protocol type. The packet identifier is also generally obtained from the extracted packet header. For the IPv4 packet, the identifier field (Identification) field and the fragment offset (Fragment-offset) of the IP packet header can be determined as unique identifiers. Packet ID of the packet.

As shown in FIG. 2, in the prior art, the specific process of passive measurement for a measurement task is as follows:

Step 200: The measurement controller configures the measurement point. The configuration includes: the quintuple of the measured stream, the measurement start time, and the measurement end time. If you need to use sampling, you also need to provide a sampling algorithm.

Step 205: The measurement points A and B are configured according to the configuration, and when the measurement start time is reached, the target message is extracted according to the quintuple of the measured flow and the timestamp information is attached; and the flow identifier and the message identifier are generated according to the content of the extracted message.

Step 210: The measurement points A and B combine the flow identifier, the packet identifier, and the timestamp information into a packet summary data transmission measurement data collector.

Step 215: The collector receives the packet digest data of the measurement points A and B, compares the packet digest data received from the measurement points VIII and B, matches the flow identifier and the packet identifier, compares the timestamps, and obtains a single packet. Delay. If a message identifier appears in the message digest data collected from measurement point A and does not appear in the message digest data collected from measurement point B, then the message is judged to be lost.

Step 220: The collector calculates the network performance indicators in a calculation interval according to the delay of the single packet and the packet loss, that is, the average delay, the maximum delay, the minimum delay, the delay jitter, and the packet loss rate. Network unavailability, etc.

Step 225: The collector sends performance indicators such as average delay, maximum delay, minimum delay, delay jitter, packet loss rate, and network unavailability to the measurement controller. Step 230: The measurement controller reports the performance index of the text network to the user or other operators. After the measurement end time is reached, the measurement point stops extracting the target message.

Although the above scheme is capable of passive measurement, the inventors found the following problems during the development process:

(1) Existing passive measurements do not take into account the measurement of the aggregate flow. Although a quintuple can be used to describe the data flow between two hosts, the measured flow may be a data flow between two networks or other forms of aggregated flow. At this point, the quintuple cannot be used to describe the measured Flow, so measurement is not possible.

(2) Since the stream identifier is generated according to the extracted packet header information, when the measured stream is a data stream between the two networks, the stream identifier cannot be generated by using the extracted packet header information. For example: From 100.1.1.0/24 to 200.1.1.0/24, the description of this aggregated flow should be composed of "source network address 100.1.1.0/24, destination network address 200.1.1.0/24, priority information," The packet header does not contain mask information, so the stream identifier of this aggregated stream cannot be obtained from the packet header.

(3) According to the identifier (Identification) field and the fragment offset (Fragment-offset) in the IPv4 header, the identifier is used as the text. For communication between two hosts, the Identification field and the Fragment-offset can be used as fields that uniquely identify the message. However, for an aggregated stream, there may be communication between multiple hosts, so both the identifier field and the fragment offset (Fragment-offset) are likely to be duplicated. In this case, the identifier field and the fragment offset cannot be used as the text identifier, and the generation of the packet identifier does not take into account the IPv6 environment, because there is no IPv4 identifier in the IPv6 header. Field and fragment offset fields. Summary of the invention

The embodiment of the invention provides a network performance measurement method and system, which can solve the problem that the network performance measurement cannot be performed for the aggregated flow in the existing measurement; further solve the problem that the packet identification may not be obtained and the measurement is affected.

A network performance measurement method includes the following steps:

> assigning a flow identifier to the measured flow according to the network performance measurement request, and configuring the flow identifier and the flow description of the measured flow to the measurement point; The measurement point extracts the packet belonging to the measured flow according to the flow description, and generates the packet summary data including the flow identifier and the packet identifier, and generates the packet summary data;

The matching stream identifier and the 艮标识 identifier identify the scorpion digest data reported by different measurement points and belong to the same essay, and calculate the network performance metric according to the packet digest data.

A network performance measurement method includes the following steps:

Configuring a flow description of the measured flow to the measurement point according to the network performance measurement;

The measurement point extracts the packet that belongs to the measured flow according to the flow description, generates a flow identifier according to the flow description, and generates message summary data including the flow identifier and the packet identifier, and reports the data;

The matching flow identifier and the packet identifier determine the summary data of the packets that are reported by the different measurement points and belong to the same packet, and calculate the network performance indicator according to the packet summary data.

A network performance measurement system includes: a measurement controller, a collector, and a measurement device; the measurement controller allocates a flow identifier for the measured flow according to the network performance measurement request, and configures the flow identifier and the flow description of the measured flow to Measuring device

The measuring device extracts the packet belonging to the measured flow according to the flow description, generates the packet summary data including the flow identifier and the message identifier, and reports the packet summary data to the collector;

The collector calculates a network performance indicator according to the reported message summary data, and sends the network performance indicator to the measurement controller.

A network performance measurement system includes: a measurement controller, a collector, and a measurement device; the measurement controller configures a flow description of the flow to be measured according to a network performance measurement request;

The measuring device extracts a packet belonging to the measured flow according to the flow description, generates a flow identifier according to the flow description, and generates message summary data including the flow identifier and the packet identifier, and reports the packet summary data to the collector; The network performance indicator is calculated according to the reported message summary data and sent to the measurement controller.

In the embodiment of the present invention, the flow identifier is allocated by the measurement controller, or the flow point identifier is generated by the measurement point according to the flow description of the measured flow, instead of being obtained from the extracted target message, and therefore, the measurement of the micro flow and the aggregate flow can be supported. . According to the content of the header of the extracted IP packet and the content of the payload part It can not only support IPv4 and IPv6 formats, but also support streaming (determination of a stream by IPv4 quintuple or IPv6 triple) and measurement of aggregated flows. DRAWINGS

1 is a schematic structural view of a measurement system in a prior art;

2 is a flow chart of implementing passive measurement in the prior art;

FIG. 3 is a flow chart of implementing passive measurement by a process controller by assigning a process identifier according to an embodiment of the present invention;

FIG. 4 is a flow chart of passive measurement performed by a measurement point according to a flow description to generate a flow identifier according to an embodiment of the present invention. detailed description

Embodiment 1

Referring to FIG. 1, in the measurement control system, in addition to completing the existing basic functions, the measurement controller assigns a unique flow identifier to the flow description of each measured flow according to the measured request, ' The flow description and the flow identifier are configured to the measurement point, and the measurement point extracts the packet belonging to the measured flow according to the flow description, attaches the flow identifier to the generated message summary data, and reports it to the collector; the collector matches the flow identifier and The packet identifier identifies the packet digest data that is reported by the different measurement points and belongs to the same packet, and calculates the network performance indicator according to the packet digest data and reports it to the measurement controller. The measurement controller and the acquirer can be separate entities or the same entity. In this way, as long as the corresponding table of the flow identifier and the flow description is saved in the measurement controller and the measurement point, the calculation of the performance index of the collector has nothing to do according to the specific meaning of the flow identifier, as long as it can uniquely identify a measured flow, This makes it possible to achieve and improve efficiency.

' To support performance measurement of different granularity flows (including microflow and aggregated flows), and support at the same time

For IPv4 and IPv6, the description of the measured stream sent by the measurement controller to the measurement point can be one of the following descriptions:

(1) Source IP address, destination IP address, source port number, destination port number, protocol type (applies only to IPv4).

(2) source network address, destination network address, differential code point (DiffServ Code Point, DSCP) (applies only to IPv4).

(3) Source IP address, destination IP address, flow label (applies only to IPv6) ₀

(4) Source network address, destination network address, traffic type (Traffic Class) (applies only to IPv6 λ

(5) Multi-Protocol Label Switching (MPLS) label.

(6) Description of other aggregated flows.

According to the IP packet format, it can be known that the IPv4 packet or the IPv6 packet has different contents in the header of the packet and the payload of the packet in different packets. Therefore, these differences can be compared. Large fields are grouped together to form a suffix identifier that uniquely identifies a suffix.

For IPv4, you can use the identifier and the Fragment-offset to combine the part of the protocol, the source IP address, and the destination IP address. Or the contents of all the fields to generate a message identifier; further, a part of the payload data (generally, the first 20 bytes of the payload portion) may be added to generate a message identifier.

For IPv6, the Payload Length, the Next Header, the Source IP address, and the Destination IP address are used to generate the 4 艮 identifier; further, it can be added The upper partial payload data (generally, the first 20 bytes of the payload portion can be generated) generates a ^^ text identifier.

In order to save storage space and network resources as much as possible, a suitable function can be used (ie, it can avoid the occurrence of message identification conflicts, that is, the message identification is unique during the measurement), and generate a text identifier according to the above fields, for example, using a loop. Check code function (CRC32), compression function or hash function (HASH).

Referring to FIG. 3, the process of implementing the passive measurement by the flow controller by the measurement controller is as follows: 'Step 300, the measurement controller assigns a flow identifier to the measured flow and configures the measurement point. The configuration includes: a flow identifier of the measured flow, a flow description of the measured flow, a measurement start time, and a measurement end time. If you need to apply sampling, you also need to provide a sampling algorithm. The flow is described as one of the foregoing descriptions. Step 305: When the measurement start time is reached, the measurement points A and B respectively extract the target message according to the measured flow description and attach the time stamp information, and at the same time, adopt an identifier (Identification), a fragment offset (Fragment-offset), The protocol type, the source IP address, and the destination IP address are used to generate the suffix identifier (using IPv4 as an example).

Step 310: The measurement points A and B respectively combine the flow identifier, the packet identifier, and the timestamp information into the message summary data and send the data to the collector.

Step 315: The collector receives the packet digest data of the measurement points A and B, compares the packet digest data received from the measurement points A and B, matches the flow identifier and the packet identifier, compares the time stamps, and obtains a single packet. Delay.

If a message identifier appears in the message digest data collected from measurement point A and does not appear in the message digest data collected from measurement point B, it is determined that the message is lost.

Step 320: The collector calculates the network performance indicators in a calculation interval according to the delay of the single packet and the packet loss, that is, the average delay, the maximum delay, the minimum delay, the delay jitter, and the packet loss rate. Network unavailability, etc.

Step 325: The collector sends performance indicators such as average delay, maximum delay, minimum delay, delay jitter, packet loss rate, and network unavailability to the measurement controller.

Step 330: The measurement controller reports the performance index of the text network to the user or other operators. After the measurement end time is reached, the measurement point stops extracting the target message.

Embodiment 2

As shown in FIG. 1 , in the measurement control system of the embodiment, the flow identifier is obtained by the flow description of the measured flow that is sent by the measurement controller, instead of from the extracted target information. obtain. In this way, turbulence measurements can be supported while also supporting the measurement of aggregated flows. Measuring point The field described by the measured stream can be subjected to a function operation to calculate a stream identifier. This calculation function can be a cyclic redundancy code (CRC16, CRC32) function, a compression function or a hash function (HASH), as long as the stream identifier generated by the function is guaranteed to be unique during the measurement period. In this way, a fixed-length stream identifier can be generated, which also helps to match the packet summary data.

The flow description of the measured stream and the manner of generating the text are the same as those in the first embodiment. Referring to FIG. 4, the process of generating a flow identifier according to the flow description to implement passive measurement is as follows: Step 400: The measurement controller configures the measurement point. The configuration includes: a flow description of the measured flow, a measurement start time, and a measurement end time. If you need to apply sampling, you also need to provide a sampling algorithm. The flow is described as one of the foregoing descriptions.

Step 405: When the measurement start time is reached, the measurement points A and B respectively extract the target message according to the measured flow description and attach the time stamp information; meanwhile, generate a flow identifier by using a cyclic redundancy code function according to the field in the measured description, and Use the Payload Length, Next Header, Source IP address, Destination IP address, and the first 20 bytes of the payload to generate the text identifier (in IPv6). example).

Step 410: The measurement points A and B respectively combine the flow identifier, the packet identifier, and the timestamp information into the packet summary data and send the data to the collector.

Step 415: The collector receives the packet summary data of the measurement points A and B, compares the packet summary data received from the measurement points A and B, matches the flow identifier and the identifier, compares the time stamp, and obtains a single ^ The delay of the text.

Step 420: The collector calculates the network performance indicators in a calculation interval according to the delay of the single packet and the packet loss, that is, the average delay, the maximum delay, the minimum delay, the delay jitter, and the packet loss rate. And network unavailability, etc.

Step 425: The collector sends performance indicators such as average delay, maximum delay, minimum delay, delay jitter, packet loss rate, and network unavailability to the measurement controller.

Step 430: The measurement controller reports the performance indicators of the network to the user or other operators. After the measurement end time is reached, the measurement point stops extracting the target message.

From the above, it can be used to support not only IPv4 and IPv6 formats, but also microflow (determining a stream by IPv4, quintuple or IPv6 or triple) and aggregated flow measurements.

In the embodiment of the present invention, the flow identifier is allocated by the measurement controller, or the flow point identifier is generated by the measurement point according to the flow description of the measured flow, instead of being obtained from the extracted target message, and therefore, the micro flow can be supported. And measurement of aggregated flows. The packet identifier is generated according to the content in the header of the extracted IP packet and the content of the payload portion, and not only supports the IPv4 and IPv6 formats, but also supports the microflow (determining a flow by the IPv4 quintuple or the IPv6 triplet) And the measurement of the aggregate flow. The spirit and scope of the invention. Thus, it is intended that the present invention cover the modifications and the modifications of the invention

Claims

Rights request

A network performance measurement method, comprising the steps of:

Assigning a flow identifier to the measured flow according to the network performance measurement request, and configuring the flow identifier and the flow description of the measured flow to the measurement point;

The measurement point extracts the packet belonging to the measured flow according to the flow description, and generates and reports the packet summary data including the packet identifier and the assigned flow identifier;

Calculate network performance indicators based on packet summary data.

2. The method according to claim 1, wherein the measurement point further attaches timestamp information after extracting the message, and carries the timestamp information in the message summary data.

3. The method according to claim 1, wherein the measurement point generates a message identifier according to the content in the packet header; or generates a message identifier according to the content in the packet header and the content of the payload portion.

The method according to claim 3, wherein, in the IPv4 format message, the content in the packet header includes an identifier and a fragment offset field content in the packet header, and a protocol type, The content of some or all of the source and destination addresses.

The method according to claim 3, wherein, in the IPv6 format message, the content in the packet header includes a payload length, a next header, a source address, and a destination address field in the packet header. Content.

The method according to claim 3, 4 or 5, characterized in that the content in the message header or the content of the content in the header and the content of the payload portion are subjected to a function operation to generate a message identifier.

7. The method of claim 1 wherein the stream of the stream being measured is described as one of the following descriptions:

(1) source IP address, destination IP address, source port number, destination port number, and protocol type;

(2) source network address, destination network address, and differential code point;

(3) source IP address, destination Π>address and flow label;

(4) source network address, destination network address, and traffic type;

(5) MPLS label.

8. A network performance measurement method, comprising the steps of:

The measurement point is used to extract a packet that belongs to the measured flow, and generates a flow identifier according to the flow description, and generates a message summary data including the flow identifier and the packet identifier, and reports the data;

Calculate network performance indicators based on packet summary data.

9. The method according to claim 8, wherein the measurement point further attaches timestamp information after extracting the message, and carries the timestamp information in the message summary data.

10. The method according to claim 8, wherein the content of the field in the stream description is subjected to a function operation to generate a stream identifier.

The method according to claim 8, wherein the measurement point generates a message identifier according to the content in the message header; or, the message identifier is generated according to the content in the message header and the content of the payload portion.

The method according to claim 11, wherein, for the IPv4 format message, the content in the packet header includes an identifier and a fragment offset field content in the header, and a protocol type, The content of some or all of the source and destination addresses.

The method according to claim 11, wherein, for the IPv6 format message, the content in the packet header includes a payload length, a next header, a source address, and a destination address field in the header. Content.

The method according to claim 11, 12 or 13, wherein the content of the message header or the content of the content and the payload portion of the header is subjected to a function operation to generate a message identifier.

15. The method of claim 8 wherein the stream of the stream being measured is described as one of the following descriptions:

(3) source IP address, destination IP address, and flow label;

(4) source network address, destination network address, and traffic type;

(5) MPLS label.

16. A network performance measurement system, comprising: a measurement controller, a collector, and a measurement device;

The measurement controller allocates a flow identifier for the measured flow according to the network performance measurement request, and configures the flow identifier and the flow description of the measured flow to the measurement device;

17. The system according to claim 16, wherein the measuring device generates a message identifier according to the content in the packet header; or generates a message identifier according to the content in the packet header and the content of the payload portion.

18. A network performance measurement system, comprising: a measurement controller, a collector, and a measurement device;

The measurement controller configures a flow description of the measured flow to the measurement point according to the network performance measurement request;

The measuring device extracts a packet belonging to the measured flow according to the flow description, generates a flow identifier according to the flow description, and generates message summary data including the flow identifier and the packet identifier, and reports the packet summary data to the collector; The network calculates the network performance indicator based on the message digest data of the upper node and sends it to the measurement controller.

19. The system of claim 18, wherein the measuring device is based on a header in the message header

■ The content generation message identifier; or, the message identifier is generated according to the content in the header and the content of the payload portion.