CN101237392A - A Method for Testing Network Faults in Asynchronous Transfer Mode - Google Patents

Abstract

The invention discloses an asynchronous transfer mode network fault testing method which comprises the following steps that: step one, a sending network element and a receiving network element adopt a service specific connection oriented protocol to transmit data; step two, the sending network element sends a test request data packet to the receiving network element; step three, the receiving network element receives the test request data packet sent by the sending network element and then sends a test response data packet to the sending network element; step four, the sending network element judges whether the test response data packet is received, the step five is executed if the test response data packet is received; step five, the sending network element compares the time of receiving the test response data packet with the time of sending the test response data packet to obtain the time delay of the data.

Description

A Method for Testing Network Faults in Asynchronous Transfer Mode

technical field

The invention relates to the field of asynchronous transfer mode (ATM) transmission, in particular to an ATM network fault testing method.

Background technique

ATM (Asynchronous Transfer Mode) is a fast packet transfer technology. ATM transmission adopts the ATM cell format with fixed byte length to transmit in the network in an asynchronous manner. The ATM data transmission mode is carried out according to the ATM protocol model, and the ATM protocol reference model includes the physical layer, the ATM layer, the adaptation layer AAL (or the signaling adaptation layer SAAL) and high-level applications. AAL adapts high-level information into ATM letter yuan so that it can be transmitted through the ATM network, and then takes the information out of the ATM letter yuan and submits it to the upper level.

Since AAL5 can realize high-efficiency data service transmission adaptation, the AAL5 adaptation type is widely used in data transmission of signaling services. The corresponding protocol AAL is called SAAL (Signaling ATM Adaptation Layer), and the Service Specific Connection Oriented Protocol (SSCOP, Service Specific Connection Oriented Protocol) protocol is the convergence sublayer protocol of SAAL, which ensures the reliability of SAAL application data transmission.

ATM transmission is widely used in telecommunications and communication network transmission, especially for data transmission between two network elements in an ATM network, while AAL5 (ATM Adaptation Layer Type 5) is mainly used for control signaling transmission in WCDMA. The transmission performance between network elements directly affects the progress of high-level services. Therefore, it is particularly important to monitor and track network performance.

In practical applications, the SSCOP protocol can only judge the network situation from the data received at the local end. For example, it is difficult to determine the one-way transmission packet loss caused by the network bandwidth. For example, if there is a switching device connected between two network elements, if the bandwidth of the switching device is lower than the processing bandwidth of the network element, small data packets can be sent between the two network elements, but large data packets cannot be sent to the opposite party. side anomalies. However, the SSCOP protocol cannot directly locate such faults. Therefore, a method is considered to detect similar network transmission abnormalities.

Contents of the invention

The technical problem to be solved by the present invention is to detect in real time the abnormal situation that small packet data can be sent but large packet data cannot be sent on the network when using SSCOP protocol to carry out ATM data transmission between two network elements of the ATM network, and adopt SSCOP A specific type of protocol data unit (PDU) in the protocol performs network detection and provides users with a means of location testing.

For this reason, the invention provides a kind of ATM network failure testing method, comprises steps:

Step 1, using a service-specific connection-oriented protocol for data transmission between the sending network element and the receiving network element;

Step 2, the sending network element sends a data packet in a specific format to the receiving network element;

Step 3: After the receiving network element receives the data packet of the specific format sent by the above-mentioned sending network element, it detects whether the type of the data packet of the specific format is a specific type. If it is a specific type, the data packet of the specific format is a test To request a data packet, go to step 4;

Step 4, the receiving network element sends a test response data packet to the sending network element;

Step 5. The sending network element judges whether the test response data packet is received, and if the test response data packet is received, step 6 is performed;

Step 6: The sending network element compares the time of receiving the test response data packet with the time of sending the test request data packet to obtain the data delay.

Wherein, the data packet in a specific format is a data packet in a service-specific connection-oriented protocol protocol data unit format.

Wherein, the specific type is 0 as the protocol data unit type.

Wherein, the test request data packet has a packet sequence number part, a test request message number, a network element characteristic information part and a filling part.

Wherein, the network element feature information part includes the time when the test request data packet is sent.

Wherein, the step 3 also includes steps:

If the type of the data packet in the specific format is not a specific type, the receiving network element processes the data packet sent by the sending network element according to the service-specific connection-oriented protocol.

Wherein, the test response data packet has a packet sequence number part, a test response message number, a network element characteristic information part and a filling part.

Wherein, the network element feature information part includes time information when the receiving network element receives the test request data packet sent by the sending network element.

Wherein said step five also includes steps:

If the test response data packet is not received, the sending network element reduces the length of the data packet.

The present invention also provides an asynchronous transfer mode network fault testing method, comprising the steps of:

Step 1, using a service-specific connection-oriented protocol for data transmission between the sending network element and the receiving network element;

Step 2, the sending network element sends a test request packet to the receiving network element;

Step 3: After receiving the test request data packet sent by the sending network element, the receiving network element sends a test response data packet to the sending network element;

Step 4, the sending network element judges whether the test response data packet is received, and if the test response data packet is received, step 5 is performed;

Step 5, the sending network element compares the time of receiving the test response data packet with the time of sending the test request data packet to obtain the data delay.

Wherein, the PDU type of the test request data packet is 0.

Wherein, the test request data packet has a packet sequence number part, a test request message number, a network element characteristic information part and a filling part.

Wherein, the network element feature information part includes the time when the test request data packet is sent.

Wherein, the test response data packet has a packet sequence number part, a test response message number, a network element characteristic information part and a filling part.

Wherein, the network element feature information part includes time information when the receiving network element receives the test request data packet sent by the sending network element.

Wherein said step 4 also includes steps:

If the test response data packet is not received, the sending network element reduces the length of the data packet. .

Since the SSCOP protocol itself provides end-to-end data transmission, various user data can be carried on it. Therefore, adopting this protocol can easily realize the transmission of user-defined test data. Moreover, the user designs a corresponding test process according to the transmission status of the SSCOP network at that time, and the test process has little impact on the normal communication of the network.

By adopting the above-mentioned method of the present invention, the user can start a test from any network element at any time to view the network status. Especially when abnormal network communication is found, the test can quickly find out the reasons that affect the quality of network transmission, and improve the processing efficiency of network faults.

Description of drawings

Fig. 1 is a flowchart of an embodiment of the present invention;

FIG. 2 is a schematic diagram of data transmission between network elements using the SSCOP protocol;

Figure 3 is a schematic diagram of the SSCOP PDU format carrying test data packets.

Fig. 4 is a schematic diagram of the test request packet format;

Fig. 5 is a schematic diagram of sending a test request packet whose length is L;

Fig. 6 is a schematic diagram of the test response packet format;

Fig. 7 is a schematic diagram of returning a test response packet;

Fig. 8 is a flowchart of another embodiment of the present invention.

Detailed ways

The specific implementation manner of the present invention will be described in detail below in conjunction with the accompanying drawings.

Fig. 1 is a flowchart of an embodiment of the present invention. As shown in Figure 1, ATM network failure testing method provided by the present invention comprises the following steps:

Step S1, establish a data transmission protocol between network elements, specifically, use the SSCOP protocol for data transmission between the sending network element 1 and the receiving network element 2; Figure 2 is a schematic diagram of data transmission using the SSCOP protocol between network elements, as shown in As shown in 2, the SSCOP protocol is located in the protocol stacks of the sending network element 1 and the receiving network element 2;

Step S2, sending a data packet in a specific format between network elements; that is, the sending network element 1 sends a data packet in the SSCOP PDU format to the receiving network element 2, and waits for a response at a specified time interval; Figure 3 defines the SSCOP PDU carrying the data packet Format. As shown in Figure 3, according to the ITU standard Q.2110, the SSCOP protocol defines a total of 15 PDU types, and the corresponding PDU types are from 1 to 15. Since each PDU has its own usage method, PDU type 0 is used as the test The bearer of the request data packet, that is, if the PDU type is a specific type, that is, if the PDU type is 0, the data packet is a test request data packet; this can avoid conflicts with other PDUs, and name the PDU as PINGPDU; Figure 4 defines the format of the test request data packet, as shown in Figure 4, the test request data packet has a packet sequence number part, a test request message number, a network element characteristic information part and a filling part; Schematic diagram of network element 2 sending a test request packet with a length of L, as shown in Figure 5, the sending network element 1 encapsulates a test request packet with a size and length of L through SSCOP PDU type 0, and the network element characteristics of the test request packet The information part includes information such as the current time for sending the test request data packet, and then the sending network element 1 sends the test request data packet to the receiving network element 2, and the sending network element 1 starts the timeout timer;

Step S3, after receiving the data packet sent by the above-mentioned sending network element 1, the receiving network element 2 detects whether the type of the PDU in the data packet is a specific type; if it is a specific type, that is, if the PDU type is 0, the receiving network Element 2 judges that the data packet is a test request data packet, and executes step S4; otherwise, if the receiving network element 2 detects that the type of PDU in the received data packet is not a specific type, that is, if the PDU type is not 0, then receive For other types of PDUs, step S5 is performed;

Step S4, the receiving network element 2 sends a test response data packet to the sending network element 1; the details are as follows: Figure 6 is a schematic diagram of the format of the test response data packet, as shown in Figure 6, the test response data packet has a packet sequence number part, and the test response message No., the network element characteristic information part and the filling part, wherein the network element characteristic information part includes information such as the time when the receiving network element 2 receives the test request data packet sent by the sending network element 1; Network element 1 returns a schematic diagram of the test response data packet, as shown in Figure 7. After receiving the test request data packet, the receiving network element 2 modifies the test request message number to the test response message number, and adds The receiving network element 2 sends information such as the current time of the test response data packet, wherein the network element characteristic information and other parts remain unchanged, and then the receiving network element 2 sends the test response data packet to the sending network element 1;

Step S5, the receiving network element 2 processes the data packet sent by the sending network element 1 according to the SSCOP protocol;

Step S6, the sending network element 1 judges whether the test response data packet is received; specifically, if the test response data packet is received within the time specified by the timeout timer, step S7 is performed; if the test response data packet is not received within the time specified by the timeout timer When the test response data packet is received, step S8 is executed;

Step S7, after receiving the test response packet, the sending network element 1 analyzes the network element characteristic information in the test response packet for statistics, and compares the time of receiving the test response data packet with the time of sending the test request data packet to obtain The delay of outgoing data. If there is a delay, it means that there is a large packet loss between the network elements. Therefore, the user can construct different time intervals and different sizes of data packets to test the network, so that the network can be tested according to the data sending and receiving situation. Judgment of network status;

Step S8, if the test response data packet is not received within the time specified by the timeout timer, it means that the network is faulty, and then the sending network element reduces the length of the data packet to be sent.

In addition, according to another embodiment of the present invention, the sending network element 1 can directly send the test request data packet to the receiving network element 2, as shown in FIG. 8:

Step S21, establish a data transmission protocol between network elements, specifically, use the SSCOP protocol for data transmission between the sending network element 1 and the receiving network element 2; FIG. 2 is a schematic diagram of using the SSCOP protocol for data transmission between network elements, as shown in FIG. As shown in 2, the SSCOP protocol is located in the protocol stacks of the sending network element 1 and the receiving network element 2;

Step S22, sending network element 1 sends this test request packet to receiving network element 2; Specifically as follows: Fig. 4 has defined the format of test request packet, as shown in Fig. 4, this test request packet has packet sequence number part, test Request message number, network element characteristic information part and padding part; as shown in Figure 5, sending network element 1 encapsulates a test request data packet with a size and length L through SSCOP PDU type 0, and the network element characteristic information part of the test request data packet Including information such as the current time of sending the test request data packet, then the sending network element 1 sends the test request data packet to the receiving network element 2, and the sending network element 1 starts the timeout timer;

Step S23, after receiving the test request packet sent by the sending network element 1, the receiving network element 2 sends a test response packet to the sending network element 1; the details are as follows: Figure 6 is a schematic diagram of the format of the test response packet, as shown in Figure 6 As shown, the test response data packet has a packet sequence number part, a test response message number, a network element characteristic information part and a filling part, wherein the network element characteristic information part includes information such as the time when the receiving network element 2 sends the test response data packet; Fig. 7 is a schematic diagram of the test response data packet returned by the receiving network element 2 to the sending network element 1. As shown in Fig. 7, after receiving the test request data packet, the receiving network element 2 modifies the test request message number to the test response message number, And add information such as the current time when the receiving network element 2 sends the test response data packet in the network element characteristic information part, and other parts remain unchanged, and then the receiving network element 2 sends the test response data packet to the sending network element 1;

Step S24, the sending network element 1 judges whether the test response data packet is received; specifically, if the test response data packet is received within the time specified by the timeout timer, step S25 is performed; if the test response data packet is not received within the time specified by the timeout timer When the test response packet is received, step S26 is performed;

Step S25, after the sending network element 1 receives the test response packet, it analyzes the network element characteristic information in the test response packet for statistics, and compares the time of sending the test response data packet with the time of sending the test request data packet to obtain The delay of data, if there is a delay, it means that there is a large packet loss between the network elements, so the user can construct different time intervals and different sizes of data packets to test the network, so that the network can be adjusted according to the data sending and receiving situation. Judgment of status;

Step S26, if the test response data packet is not received within the time specified by the timeout timer, it means that the network is faulty, and then the sending network element reduces the length of the data packet to be sent.

Of course, the present invention can also have other various embodiments, and those skilled in the art can make various corresponding changes and deformations according to the present invention without departing from the spirit and essence of the present invention, but these corresponding Changes and deformations should belong to the scope of protection of the appended claims of the present invention.

Claims (16)

1. network failure testing method under asynchronous transmission mode comprises step:

Step 1 adopts professional specific connection oriented protocol to carry out transfer of data at transmission network element and reception network element;

Step 2 sends network element to receiving the packet that network element sends specific format;

Step 3, after the reception network element was received the packet of the specific format that above-mentioned transmission network element is sent, whether the type that detects the packet of this specific format was particular type, if particular type, then the packet of this specific format is the test request packet, execution in step four;

Step 4 receives network element and sends the test response data bag to sending network element;

Step 5, transmission network element judge whether to receive the test response data bag, if receive the test response data bag then execution in step six;

Step 6 sends network element and will receive that the time of this test response data bag and the time that sends this test request packet compare the time-delay that draws data.

2. the method for claim 1 is characterized in that, wherein, the packet of described specific format is the packet of the protocol Data Unit form of professional specific connection oriented protocol.

3. method as claimed in claim 2 is characterized in that, wherein, described particular type is 0 for the protocol Data Unit type.

4. as claim 1 or 3 described methods, it is characterized in that wherein, described test request packet has bag sequence number part, test request message number, network element characteristic information part and filling part.

5. method as claimed in claim 4 is characterized in that, wherein, comprises the time that sends this test request packet in the described network element characteristic information part.

6. as claim 1 or 3 described methods, it is characterized in that, wherein, also comprise step in the described step 3:

If the type of the packet of this specific format is not a particular type, receives network element and handle according to the specific connection oriented protocol of business sending the packet that network element sent.

7. the method for claim 1 is characterized in that, wherein, described test response data bag has bag sequence number part, test response message number, network element characteristic information part and filling part.

8. method as claimed in claim 7 is characterized in that, wherein, comprises in the described network element characteristic information part that receiving network element receives the temporal information that the transmission network element sends the test request packet.

9. the method for claim 1 is characterized in that, also comprises step in the wherein said step 5:

If do not receive the test response data bag, send network element and reduce data packet length.

10. network failure testing method under asynchronous transmission mode comprises step:

Step 1 adopts professional specific connection oriented protocol to carry out transfer of data at transmission network element and reception network element;

Step 2 sends network element and sends the test request packet to receiving network element;

Step 3, receive the test request packet that network element receives that above-mentioned transmission network element sent after, send the test response data bag to sending network element;

Step 4, transmission network element judge whether to receive the test response data bag, if receive the test response data bag then execution in step five;

The time that step 5, transmission network element will receive this test response data bag compares the time-delay that draws data with the time that sends this test request packet.

11. method as claimed in claim 10 is characterized in that, wherein, the PDU type of described test request packet is 0.

12., it is characterized in that wherein, described test request packet has bag sequence number part as claim 10 or 11 described methods, test request message number, network element characteristic information part and filling part.

13. method as claimed in claim 12 is characterized in that, wherein, comprises the time that sends this test request packet in the described network element characteristic information part.

14. method as claimed in claim 10 is characterized in that, wherein, described test response data bag has bag sequence number part, test response message number, network element characteristic information part and filling part.

15. method as claimed in claim 14 is characterized in that, wherein, comprises in the described network element characteristic information part that receiving network element receives the temporal information that the transmission network element sends the test request packet.

16. method as claimed in claim 10 is characterized in that, also comprises step in the wherein said step 4:

If do not receive the test response data bag, send network element and reduce data packet length.

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