WO2007107066A1

WO2007107066A1 - A method and a communication device of the loopbacked detection based on ethernet

Info

Publication number: WO2007107066A1
Application number: PCT/CN2006/003795
Authority: WO
Inventors: Shaoyun Wu; Shaowei Liu
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2006-03-18
Filing date: 2006-12-31
Publication date: 2007-09-27
Also published as: CN1859411A

Abstract

A method and a communication device of the loopbacked detection based on Ethernet. The method includes: establishing an Ethernet link of the loopbacked connection between the transmitting port and the receiving port of the communication device; sending the test message from the transmitting port and receiving the message from the receiving port; judging the Ethernet link and the device state according to the case of the message received by the receiving port. Without increasing the additional complicated mechanism, the loopbacked detection based on Ethernet can greatly improve the efficiency and flexibility of the network maintenance and the fault elimination.

Description

Loopback detection method and communication device based on Ethernet link. The application is submitted to the Chinese Patent Office on March 18, 2006, and the application number is 200610034601.X. The invention name is "Communication device link loopback detection method and communication. The priority of the Chinese Patent Application, the entire disclosure of which is incorporated herein by reference. Technical field

The present invention relates to the field of communications technologies, and in particular to a loopback detection method based on an Ethernet link and a communication device employing the same. Background technique

As people's demand for the network continues to expand and network technology continues to evolve, more and more communication devices are put into use. People use a variety of forms of links to connect these communication devices.

High-speed communication equipment commonly used in the form of point-to-point links (PPP, The Point-to-Point Protocol) and Advanced Data Link Control Protocol (HDLC), and other Gigabit Ethernet (Gigabit Ethernet) is also a common and important point-to-point link.

The PPP protocol is a data link layer protocol that provides for the delivery and encapsulation of network layer packets over a point-to-point link. PPP is mainly composed of two types of protocols: Link Control Protocols (LCP) and Network Control Protocols (NCP). The link control protocol is mainly used to establish, tear down and monitor PPP data links; the network layer control protocol family is mainly used to negotiate the format and type of data packets transmitted on the data link. PPP needs to negotiate through the session: LCP negotiation, authentication, network layer negotiation.

Ethernet technology has obvious advantages in addressing the bandwidth and capacity requirements of the network. The connection of the backbone network is developing in the direction of ultra-high speed and super capacity. Ethernet technology has always been the most popular method, with a huge network foundation and long-term insurance knowledge. Ethernet has the advantages of simple implementation, cost performance, scalability and high reliability. High-speed links use a large number of Gigabit Ethernet interfaces for fiber-optic interfaces for point-to-point transmission.

Loopback testing is commonly used to check and analyze port or line problems. In fact, due to some accidents in various aspects such as design and construction, the link cannot be transmitted normally. There are some ways to confirm which part of the link is out of order. The loopback detection method of the cartridge can often quickly locate complex practical problems.

FIG. 1 is a schematic diagram of a prior art PPP for loopback detection. The PPP protocol message can have a Magic Number, and the almost randomly generated magic word is added to the protocol message. When loopback detection is required, the sender and the receiver of one interface a need to be connected to the receiver and the sender of the other interface b, so that the packet with the magic word sent by the PPP is sent. Go out and go back to the receiving port. When PPP finds that the magic word in the received message is equal to the magic word it sent last time, it will perceive that the loopback is being performed at this time, and the interface will automatically enter the loopback state.

However, this method of loopback detection is based on the PPP negotiation mechanism. Loopback detection cannot be implemented for other links (such as Ethernet). PPP needs to establish a session and continuously maintain the session to continuously compare the transmitted and received magic words. The implementation is relatively complicated; the configuration of the PPP on the magic word is embedded in the protocol message, and the number of configurable items is small, and the use is inflexible. Summary of the invention

Embodiments of the present invention provide a method and a communication device based on loopback detection of an Ethernet link, which are used to increase link maintenance and fault diagnosis.

An embodiment of the present invention provides a method for loopback detection based on an Ethernet link, including the steps of: establishing an Ethernet link of a loopback connection between a sending port and a receiving port of the communication device; sending a test packet from the sending port, and Receiving the 4 texts from the receiving port;

The Ethernet link and the device status are determined according to the situation in which the receiving port receives the message. The embodiment of the invention provides a communication device, which has an Ethernet port as a sending port and a receiving port, and the communication device includes:

a unit that generates a test message;

a sending unit that sends a test message from the sending port;

a unit that receives a message from a receiving port;

The determining unit determines whether the received message is the test message, and when the judgment result is yes, determines that the link enters a loopback state.

In the embodiment of the present invention, for the Ethernet protocol, it is not necessary to add a PPP-like session negotiation mechanism, and the loopback can be automatically detected or loopback detection can be directly performed when necessary. The optional simplicity of the loopback detection mechanism is provided. DRAWINGS

The present invention will be described in more detail below by way of example with reference to the accompanying drawings in which: FIG. 1 is a schematic diagram of a prior art PPP for loopback detection;

2 is a schematic structural diagram of an Ethernet link loopback detection system according to an embodiment of the present invention; FIG. 3 is a flow chart of sending periodic loopback detection according to an embodiment of the present invention;

4 is a transmission flow of manual loopback detection in an embodiment of the present invention;

FIG. 5 is a flowchart of receiving periodic loopback detection according to an embodiment of the present invention; FIG.

6 is a schematic diagram of an interface state machine in an embodiment of the present invention. detailed description

Ethernet technology has significant advantages in addressing the bandwidth and capacity requirements of the network. The connection of the backbone network is developing in the direction of ultra-high speed and large capacity. Ethernet technology has the advantages of simple implementation, cost performance, scalability, and high reliability. Gigabit Ethernet with a large number of fiber interfaces is used to achieve point-to-point high-speed transmission. A point-to-point link using Ethernet technology refers to a communication link established between communication devices through an Ethernet Digital Subscriber Line, which is an Ethernet link, called an Ethernet link.

In order to make the principles, features, and advantages of the present invention clearer, the following is described in conjunction with an example of loopback detection of an Ethernet link.

2 is a schematic structural diagram of Ethernet link loopback detection between communication devices according to an embodiment of the present invention. As shown in Figure 2, an Ethernet link is used between the Ethernet optical ports of communication devices A and B.

Assume that the link between the communication device A and B (the Ethernet port and the optical port) is unreachable. You need to determine whether there is a problem with the link near the interface. In the embodiment of the present invention, it can be confirmed by the following method.

Use the cable connection c, d two points (close to the optical jumper of the A device send port and the receive port) to perform Ethernet link loopback detection. If the interface enters the loopback state, the interface of the A device and the near-end line are not faulty. Also confirm the situation on the B device side. If there is no problem, and the normal link is not connected, it can be confirmed that the line of the c-e segment or the d-f segment (between the jumpers of the devices at both ends) is faulty.

In order to achieve the above process, the following steps are required:

Adjust interface-related configuration items through the NMS or manual configuration. When an external line loopback is performed, a specific test message is issued;

If the receiving is successful, the device enters the loopback state and notifies the NMS. It also displays the command line. If the loopback status is no longer successful, the loopback status is cancelled. The loopback status is cancelled. The NMS is notified and displayed on the command line.

Next, the loopback detection of the present invention will be described in detail.

1. Adjust the related configuration items of the interface through the NMS or manual configuration.

The configurable items can include a boot mode and a timer interval.

Startup method:

A1) Periodic loopback detection. A specific test packet is periodically issued according to the timer setting to detect the loopback status.

If periodic loopback check is enabled, a specific test packet is periodically sent to detect the loopback status.

Otherwise, a specific test packet is sent periodically to detect the loopback status.

B1) Manual loopback detection. In this startup mode, you can specify the test packet to be sent out by the command line.

By default, periodic loopback detection is enabled.

Timer interval:

A2) Send timer Tl. Interval at which the test status of a specific test packet is sent during periodic loopback detection. The default is 3 seconds.

Β 2) Receive timer Τ2. The allowed interval between the periodic loopback detection packets and the received packets. The default is 1 millisecond.

C2) Manual loopback detection state revocation time Τ3. After the manual loopback detection succeeds, it enters the loopback state. After how long, the loopback state is automatically revoked.

The default is 3 seconds.

1. When performing external line loopback, a specific test message is sent.

For Ethernet, the frame header structure is defined as follows (taking Ethernet I I as an example):

The type of load message is discriminated based on the type field.

The type number used for loopback detection packets is, for example, 8999.

For the loopback detection message of the load after Ethernet encapsulation, the following format can be observed:

. 0 1 2 3 45 6 7 8 9 0 1 2 3 45 6 78 9 0 1 2 3 4 5 6 7 8 9 0 1

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- +-+-+-+-+-+-+-+

I Type I Length I Loopback Word I + One + One ₊ One + One + One + - + - + - + - Eleven + One + One + One + One + One + - + - + - + + - + —+——+—+— +—+—+— +—+—+—+_+

I loopback word I

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Type: 1

Length: 6

Loopback word: A 4-byte random number greater than 0. After receiving the loopback detection packet, the interface compares the received loopback word with the loopback word sent last time.

3. If the receiving is successful, notify the NMS and display it on the command line to enter the loopback state.

When the interface receives the loopback detection packet, it compares the received loopback word with the loopback word sent last time. If they are the same, the interface is considered to be in loopback state. The network management software is notified. The interface status is loopbacked on the command line. If no loopback detection packet is received, or the loopback word of the received detection packet is different from the one sent last time, the interface remains in its original state.

4. If the detection packet is no longer successfully received in the loopback state, the loopback status is revoked, the network management is notified, and the command line is displayed.

After the interface enters the loopback state, if the packet with the same loopback word is not received within the timer T2 after the loopback detection packet is sent, the loopback state is revoked, the original state is entered, and the network management software is notified. Displayed under the command line.

The entire flow of loopback detection in the embodiment of the present invention includes three parts as shown in Figs. 3, 4 and 5.

FIG. 3 is a flow chart of sending periodic loopback detection, and the specific steps are as follows: In step 310, the sending timer T1 is started, and the timer Τ2 is received.

In step 320, it is judged whether T1 is up. If no, the decision is continued. If yes, go to step 330.

Step 330, constructing a loopback word, recording.

Step 340: Send a loopback detection packet.

Step 350, clearing the timer T1, and returning to the beginning of the process.

Figure 4 shows the transmission process of manual loopback detection. The specific steps are as follows:

Step 410: Manually input a loopback detection command. At step 420, a loopback word is constructed, recorded. At step 430, a loopback detection message is sent.

Figure 5 is a flow chart of receiving periodic loopback detection. The specific steps are as follows:

Step 510: The interface receives an Ethernet packet.

Step 520: Determine whether the destination MAC=interface MAC? If no, go to step 530 to perform the original normal processing; if yes, go to step 540.

Step 540, determining whether the type is = 8999? If not, proceeding to step 530; if yes, proceeding to step 550.

Step 550, determining whether the loopback word received = the loopback word sent last time? If yes, go to step 560 to discard the message; if no, go to step 570.

Step 570: The timer starts counting from the sending loop report, and determines whether the receiving timer T2 times out? If it times out, the process goes to step 580, the timer T2 is cleared, and then in step 590, the original state is entered.

If it has not timed out, the process proceeds to step 600, and the timer T2 is cleared.

Next, in step 610, the interface enters a loopback state.

Step 620: Determine whether to manually loopback detection? If no, go to step 630 and the interface will maintain the loopback status.

If yes, proceed to step 640 to determine if the deactivation timer Τ3 has expired. Otherwise continue the decision step.

If yes, proceed to step 650 to clear the timer Τ3. Then, the process proceeds to step 660, where the original state is entered and the network management is reported.

Figure 6 is a schematic diagram of an interface state machine. If the detection packet receives timeout, it is judged as non- Loopback status. If the detection packet reception does not time out, it is determined to be in the loopback state.

It can be seen from the above specific embodiments of the present invention that the method provided by the present invention can perform loopback detection based on the Ethernet link without adding additional complicated mechanisms, thereby greatly improving the efficiency and flexibility of network maintenance and troubleshooting.

It should be noted that the present invention is applicable to Ethernet link loopback detection of optical communication equipment.

It is to be understood that the invention described herein may be susceptible to many modifications and variations may be made without departing from the spirit and scope of the invention. Therefore, all changes and equivalents that are obvious to those skilled in the art are included in the scope of the present invention.

Claims

Rights request

A method for loopback detection based on an Ethernet link, comprising the steps of: establishing an Ethernet link of a loopback connection between a sending port and a receiving port of the communication device; and sending a test packet from the sending port, And receiving the message from the receiving port;

The Ethernet link and the device status are determined according to the situation in which the receiving port receives the message.

The method according to claim 1, wherein the test message includes an address of the receiving port and/or a loopback word and/or a type number, wherein the loopback word is a random number.

The method of claim 1, wherein the step of sending a test packet from the sending port comprises: sending the test packet periodically, specifically:

a step of setting a first timer, where the first timer determines a time interval during which the test message detection state is periodically issued;

A step of setting a second timer, the second timer determining an allowable time interval between the sending of the test message and the receipt of the test message.

The method according to claim 3, wherein the issuing the test from the sending port is done manually.

The method according to claim 4, further comprising: setting a third timer, and determining, by using the third timer, a time interval for automatically revoking the loopback state after the loopback detection enters a loopback state.

A communication device having an Ethernet port as a transmitting port and a receiving port, comprising:

a unit that generates a test message;

a sending unit that sends a test message from the sending port;

a unit that receives a message from a receiving port;

7. The communication device according to claim 6, wherein the means for generating a test message uses a random number as a loopback word of the test message.

8. The communication device according to claim 6, comprising: a first timer and a second timer, wherein the generating device and the transmitting device are separated according to a time interval determined by the first timer The test message is periodically sent, and the second timer determines an allowable time interval between the test message and the test message being received.

9. The communication device according to claim 6, comprising a third timer, an interval.