LISP protocol-based air-ground data link switching time delay test method for aviation telecommunication network

Abstract

The invention provides an LISP protocol-based aviation telecommunication network ground-air data link switching time delay test method, relates to the field of civil aviation communication, and solves the problems of long time consumption, complex equipment and high cost of a traditional actual flight method. The method comprises the following steps: building a test platform which comprises corresponding equipment of at least two sets of air-ground communication systems for realizing link switching operation; the method comprises the following steps: configuring an LISP protocol for multiple types of routers in a test platform, and determining a preferred ground-air communication link; configuring a channel simulator, simulating a signal transmission environment in a flight process and connecting equipment; a preferred ground-air communication link is started, and sending of test data is simulated through a computer; the first-choice ground-air communication link is closed, the first-choice ground-air communication link is automatically switched to the alternative ground-air communication link, a corresponding data packet is captured in a router packet capturing mode, and ground-air data link switching time delay is calculated; according to the invention, the test can be completed in a laboratory environment, so that the test process has the characteristics of high efficiency and low cost.

Description

Technical Field

[0001] The present invention relates to the field of civil aviation communication and is applied to a laboratory test environment. Specifically, it is a method for testing the handover delay of the air-ground data link of an aeronautical telecommunication network based on the LISP protocol. Background Art

[0002] In the future concept of air traffic management (ATM), in order to improve safety, airspace capacity, and flight efficiency, the exchange of data between the ground end and the aircraft end will increase significantly, mainly including air traffic services (ATS) and airline operational communications (AOC). The IP-based aeronautical telecommunication network (ATN / IPS) will become the new standard for future ATM infrastructure, enabling IP "end-to-end" communication as Figure 1 shown, and gradually replacing the current civil aviation communication network based on ACARS and the aeronautical telecommunication network open system interconnection (ATN / OSI) protocol. This future communication infrastructure (FCI) can achieve digital transmission of flight-critical data and voice communication between the aircraft end and the ground end ATM in a flexible, secure, and timely manner, and build a multi-link environment by using proposed future data links such as airports, ground, air, and satellites, to achieve higher communication capacity and rate.

[0003] Multi-link operation is a concept of data link usage, which refers to the simultaneous use of at least two independent air-ground data links (A / G) to meet the requirements of flight ATS services in terms of mobility, safety, and quality of service (QoS). The scope of multi-link operation applies to all airspaces except the oceanic remote (ORP) area. Multi-link operation also involves selecting the most suitable radio link for a given data service and performing seamless handover between available data links according to the quality of the currently used A / G data link or user preference settings.

[0004] LISP (Locator / ID Separation Protocol) provides a new type of network architecture that divides the IP address into a RLOC (Routing Locator) address indicating the location and an EID (Endpoint Identifier) address indicating the identity. In the core network, the RLOC address is used for forwarding, and when reaching the edge of the customer network, the outer IP address is stripped, and the EID address is used for forwarding. The ground-based LISP civil aviation communication network provides a solution for multi-link operation, which can minimize the complexity of the aircraft and the overhead of the air-ground data link, achieve seamless handover between available data links, and maintain the continuity of communication during the high-speed movement of the aircraft.

[0005] Whether the handover delay of the ground-air data link in the ATN / IPS can meet the relevant requirements of the International Civil Aviation Organization (ICAO) requires long-term testing and verification. The traditional testing method is to install ground base stations of various communication systems on the flight route and conduct flight test verification by carrying airborne terminals on the aircraft. One flight test takes a long time, the equipment installation is complex and expensive, so the resource cost in terms of manpower and material resources is huge. Therefore, how to design a more efficient and low-cost testing method for the handover delay of the ground-air data link has become the focus of attention of those skilled in the art. Summary of the Invention

[0006] Based on the current situation in the background art, the purpose of the present invention is to solve the problems of long time consumption, complex equipment and high cost existing in the current testing of the handover delay of the ground-air data link of the aeronautical telecommunication network based on the actual flight method. Therefore, a testing method for the handover delay of the ground-air data link of the aeronautical telecommunication network based on the LISP protocol is proposed. The present invention can complete the test in a laboratory environment, combine communication equipment and network equipment, make the test process efficient and low-cost, so as to provide sufficient test data support for the construction of the new generation of civil aviation communication network, save human resources, avoid time waste, and promote the digital and intelligent air traffic control construction in the civil aviation field.

[0007] The present invention adopts the following technical solutions to achieve the purpose:

[0008] A testing method for the handover delay of the ground-air data link of the aeronautical telecommunication network based on the LISP protocol, the method comprising the following steps:

[0009] S1. Based on a computer, a router and a channel simulator, build a test platform; the test platform includes the corresponding devices and subnets of at least two sets of ground-air communication systems for realizing link handover operations;

[0010] S2. For multiple types of routers in the test platform, configure the LISP protocol and the OSPF protocol correspondingly to determine the preferred ground-air communication link and the alternative ground-air communication link;

[0011] S3. Configure the channel simulator to simulate the signal transmission environment during the flight process; connect the corresponding devices of each set of ground-air communication systems to the channel simulator;

[0012] S4. Turn on the ground-air communication system corresponding to the preferred ground-air communication link, and simulate the process of sending test data from the ground station end to the aircraft end by means of computer simulation;

[0013] S5. Turn off the ground-air communication system corresponding to the preferred ground-air communication link, and the ground-air communication system corresponding to the alternative ground-air communication link automatically switches and generates test data;

[0014] S6. By means of router packet capture, capture the corresponding data packets when the preferred ground-air communication link is closed and when the alternative ground-air communication link switches successfully, and calculate the ground-air data link switching delay.

[0015] Further, the test platform built in step S1 includes an aircraft end, at least two sets of ground-air communication systems, an ATN / IPS main network, and an AOS / ATS server; each set of ground-air communication systems includes an airborne end and a ground station end connected through a channel simulator; the aircraft end and the AOS / ATS server are each configured with a corresponding computer and router, and the ATN / IPS main network is configured with a router network; the aircraft end is connected to each set of ground-air communication systems, each set of ground-air communication systems is connected to the ATN / IPS main network, and the ATN / IPS main network is connected to the AOS / ATS server.

[0016] Specifically, in each set of ground-air communication systems, use RF cables to connect the airborne end to the channel simulator and the channel simulator to the ground station end; in the aircraft end, the ATN / IPS main network, and the AOS / ATS server, use network cables to connect the corresponding computers to the routers.

[0017] Specifically, the aircraft end is constructed by a first computer and the correspondingly configured airborne router, and the airborne router is connected to the airborne end of each set of ground-air communication systems.

[0018] Specifically, each set of ground-air communication systems has a ground subnet composed of a subnet router and a border router, and the ground station end of each set of ground-air communication systems is connected to at least one subnet router of the corresponding ground subnet; each set of ground-air communication systems is connected to the ATN / IPS main network through the border router in the corresponding ground subnet.

[0019] Specifically, the ATN / IPS main network is constructed by multiple main network routers and at least one MS / MR router; the MS / MR router is used as a LISP mapping server; the ATN / IPS main network is connected to the AOS / ATS server through the main network router.

[0020] Specifically, the AOS / ATS server is constructed by a second computer and the correspondingly configured border router, and the border router is connected to the main network router in the ATN / IPS main network.

[0021] Further, in step S2, first configure the LISP protocol for the border routers of the ground subnet in each ground-air communication system and the border routers in the AOS / ATS server. Then, configure the LISP protocol for the MS / MR routers in the ATN / IPS main network. After the configuration is completed, set the EID addresses of the aircraft side and the AOS / ATS server respectively, and determine and set the preferred ground-air communication link and the alternative ground-air communication link. At the same time, configure the OSPF protocol in the subnet routers and the main network routers.

[0022] Preferably, in step S3, use computer software in cooperation with the channel simulator to generate the flight trajectory coordinate data of the aircraft for simulation testing, and import it into the channel simulator. According to the characteristics of the ground-air signal transmission environment required for the simulation test, modify the configuration parameters of the channel simulator, and then connect the channel simulator to each ground-air communication system at the same time.

[0023] Further, in step S4, generate test data through the second computer configured in the AOS / ATS server, and transmit the test data through the ground-air communication system corresponding to the preferred ground-air communication link to simulate the process of the AOS / ATS server sending data to the aircraft side. Then perform step S5, and the ground-air communication system corresponding to the alternative ground-air communication link performs an automatic switching operation when the preferred ground-air communication link is closed.

[0024] In step S6, record the moment t1 when the ground-air communication system corresponding to the preferred ground-air communication link is closed. At the same time, capture packets of the MS / MR routers in the ATN / IPS main network, and record the packet moment t2 corresponding to the closure of the preferred ground-air communication link to obtain the closure delay T1 = t2 - t1. Immediately after the alternative ground-air communication link switches successfully, capture packets of the MS / MR routers in the ATN / IPS main network, and record the packet moment t3 corresponding to the successful switch to obtain the first switching delay T2 = t3 - t2. Subsequently, when the AOS / ATS server receives data after the successful switch, capture packets of the border routers in the AOS / ATS server, and record the packet moment t4 corresponding to the received data to obtain the second switching delay T4 = t4 - t3. Thus, calculate the switching delay T from the preferred ground-air communication link to the alternative ground-air communication link as T = T1 + T2 + T3.

[0025] In summary, due to the adoption of this technical solution, the beneficial effects of the present invention are as follows:

[0026] The test method of the present invention has high flexibility and can dynamically adjust the number of network nodes according to test requirements. In addition, with the help of a channel simulator, the real environment of ground-air data propagation can be accurately simulated, and different propagation environments can be simulated by simply changing the relevant parameters. This method enables testers to select different systems under test according to actual needs and quickly build a test network that meets the requirements, so as to efficiently and accurately test the handover delay of the ground-air data link in various environments.

[0027] Compared with traditional test means, the present invention greatly reduces the test cost and time required. Traditional methods usually require deploying the ground base stations of each communication system on the ground and conducting tests by actual flight with airborne terminals carried. Each test costs up to hundreds of thousands of yuan and takes a long time. After adopting the method of the present invention, all necessary test work can be completed in a laboratory environment, which not only avoids the high flight test costs but also saves a large amount of time and resources.

[0028] The computers, communication, and network devices used in the present invention are all standard products that can be directly purchased on the market, and their reliability has been widely verified. At the same time, all parameters required for flight trajectory modeling and transmission channel simulation are supported by solid theoretical bases, ensuring the effectiveness and feasibility of the entire test process. The configuration of network protocols also follows general standards, making the test process easy to implement and operate. Brief Description of the Drawings

[0029] Figure 1 It is a schematic diagram of the future ATN / IPS aeronautical telecommunication network;

[0030] Figure 2 It is a brief flowchart of the overall process of the test method of the present invention;

[0031] Figure 3 It is a schematic diagram of the structure of the test platform built by the present invention;

[0032] Figure 4 It is a schematic diagram of the handover of the data link in the method of the present invention;

[0033] Figure 5 It is a schematic diagram of the Map-Register drop IP data packet in the embodiment of the present invention;

[0034] Figure 6 It is a schematic diagram of the Map-Register IP data packet in the embodiment of the present invention;

[0035] Figure 7 It is a schematic diagram of the Map-Reply IP data packet in the embodiment of the present invention. Detailed Embodiment

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. The components of the embodiments of the present invention usually described and illustrated in the drawings here can be arranged and designed in various different configurations.

[0037] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0038] Embodiment

[0039] A method for testing the handover delay of the ground-air data link of an aeronautical telecommunication network based on the LISP protocol Figure 2 The overall process of this method is briefly described, and its steps can be summarized as follows:

[0040] S1. Based on a computer, a router, and a channel simulator, build a test platform; the test platform includes the corresponding devices and subnets of at least two sets of ground-air communication systems for implementing link handover operations;

[0041] S2. For multiple types of routers in the test platform, configure the LISP protocol and the OSPF protocol correspondingly to determine the preferred ground-air communication link and the alternative ground-air communication link;

[0042] S3. Configure the channel simulator to simulate the signal transmission environment during flight; connect the corresponding devices of each set of ground-air communication systems to the channel simulator;

[0043] S4. Turn on the ground-air communication system corresponding to the preferred ground-air communication link, and simulate the process of sending test data from the ground station end to the aircraft end through computer simulation;

[0044] S5. Turn off the ground-air communication system corresponding to the preferred ground-air communication link, and the ground-air communication system corresponding to the alternative ground-air communication link automatically switches and generates test data;

[0045] S6. By means of router packet capture, capture the data packets corresponding to when the preferred ground-air communication link is closed and when the alternative ground-air communication link is successfully switched, and calculate the handover delay of the ground-air data link.

[0046] This embodiment will introduce detailed examples of each part of the above method, which is applicable to various civil aviation communication systems. In this embodiment, a very high frequency (VHF) radio and an L-band digital aeronautical communication system (L-DACS) are taken as examples for introduction. The VHF radio corresponds to Figure 3 the ground-air communication system 1 in the test platform shown. The L-DACS system corresponds to the ground-air communication system 2. In the test, the VHF radio will be selected as the preferred ground-air communication link, and data will be sent to the aircraft end by simulating the AOS / ATS server through a computer. After the link corresponding to the VHF radio is manually disconnected as the preferred ground-air communication link, it will automatically switch to the ground-air communication link of the L-DACS system. Then, the time for the corresponding router to update the EID-to-RLOC path due to the link disconnection error and cache it in the LISP mapping server will be calculated to achieve the test of the ground-air data link switching delay. Refer to Figure 4 for the schematic diagram.

[0047] As Figure 3 shown, the following equipment and configuration information are used in this embodiment for example.

[0048] The aircraft end is simulated by computer LIVM1 with the IP address set to 10.1.1.5; R1 is the airborne router with the IP address set to 10.1.1.1.

[0049] The ground-air data link consists of the airborne and ground station equipment of two ground-air communication systems and a channel simulator to simulate the real propagation of civil aviation ground-air data.

[0050] In the ground subnet of the ground-air communication system 1, the specific composition of multiple routers is as follows: R2 is the access router with the IP address set to 192.168.22.1; R3 and R4 are border routers (xTR) with the IP addresses set to 192.168.23.1 and 192.168.24.1 respectively.

[0051] In the ground subnet of the ground-air communication system 2, the specific composition of multiple routers is as follows: R5 is the access router with the IP address set to 192.168.11.1; R6 is the border router (xTR) with the IP address set to 192.168.12.1.

[0052] The multiple main network routers in the ATN / IPS main network include Figure 3For R7 to R13 among them, the IP addresses are respectively set to 10.0.100.1, 10.0.101.1, 10.0.102.1, 10.0.103.1, 10.0.104.1, 10.0.105.1, 10.0.106.1; meanwhile, there is additionally an MS / MR router as a LISP mapping server, and the IP address is set to 10.0.20.1.

[0053] The AOS / ATS server is simulated by the computer LIVM2, and the IP address is set to 10.2.1.4; R14 is a border router (xTR), and the IP address is set to 10.2.1.1.

[0054] In this embodiment, the above computer can adopt a personal computer, which is a general shelf product; the specific model of each router can be H3C MSR2630; the channel simulator is the Spirent Vertex series of channel simulator products produced by Spirent Communications.

[0055] In accordance with Figure 3 Connect each device in the above manner and set the corresponding IP addresses to build a test platform; in each ground-air communication system, use a radio frequency cable to connect the airborne end and the channel simulator, as well as the channel simulator and the ground station end; at the aircraft end, the ATN / IPS main network and the AOS / ATS server, use a network cable to connect the corresponding computer and the router network.

[0056] Configure the LISP protocol for routers R3, R4, R6, and R14 that are border routers (xTR). The main configuration commands are as follows:

[0057] Router(config)#system-view

[0058] Router(config)#lisp

[0059] Router(config-lisp)#itr

[0060] Router(config-lisp)#itr map-resolver 10.0.20.1

[0061] Router(config-lisp)#etr

[0062] Router(config-lisp)#database-mapping X.X.X.X X.X.X.X priority Xweight X

[0063] (Fill in 192.168.23.1 for R3, 10.0.100.5, priority 30, weight 30;

[0064] Fill in 192.168.24.1 for R4, 10.0.101.5, priority 20, weight 20;

[0065] Fill in 192.168.12.1 for R6, 10.0.102.5, priority 10, weight 10;

[0066] (Fill in 10.2.1.1 for R14, 10.0.105.5, priority 10, weight 10)

[0067] Router(config-lisp)#etr map-server 10.0.20.1 authentication-mode sha-1 authentication-key plaintext 123456

[0068] Router(config-lisp)#quit

[0069] Immediately afterwards, configure the LISP protocol for the MS / MR router acting as the LISP mapping server. Set the EID of the aircraft side to AIR, the EID of the AOS / ATS server side to ATS, and the preferred air-ground communication link EID-to-RLOC to the data link corresponding to the VHF radio (i.e., through the subnet router R3). The main configuration commands are as follows:

[0070] Router(config)#system-view

[0071] Router(config)#lisp

[0072] Router(config-lisp)#map-resolver

[0073] Router(config-lisp)#map-server

[0074] Router(config-lisp)#site A

[0075] Router(config-lisp-site-A)#authentication-mode sha-1 authentication-key plaintext 123456

[0076] Router(config-lisp-site-A)#eid-prefix 10.1.1.5 AIR

[0077] Router(config-lisp-site-A)#eid-prefix 10.2.1.4 ATS

[0078] Router(config-lisp-site-A)#database-mapping AIR 192.168.23.1 priority 30

[0079] Router(config-lisp-site-A)#quit

[0080] Router(config)#quit

[0081] Next, configure the OSPF (Open Shortest Path First) protocol for the routers in the ground subnet of the ground-air communication system and the ATN / IPS main network. The main configuration commands are as follows:

[0082] Router(config)#router ospf [process-id]

[0083] The above process completes steps S1 and S2 in the method. Next, enter step S3.

[0084] Use the dedicated tool software equipped with the channel simulator Spirent Vertex to generate the flight trajectory coordinate data of the aircraft and import it through the USB-RS232 / RJ45 cable.

[0085] According to the characteristics of the ground-air signal transmission environment required for the simulation test, set parameters such as path loss, multipath effect, and Doppler frequency shift to ensure that the signal transmission situation during the flight can be accurately simulated.

[0086] Connect the transceiver of the very high frequency (VHF) radio and the airborne and ground station ends of the L-DACS system to the two bidirectional channels of the channel simulator respectively.

[0087] The following is a detailed introduction to steps S4 to S6 in the method.

[0088] Data transmission: Through the computer LIVM2, simulate the AOS / ATS server to send test data to the aircraft end AIR.

[0089] Link switching: Close the data link corresponding to the very high frequency radio and record the closing time t1 at the same time.

[0090] Calculate the time taken for the "Map-Register drop" of the VHF radio's corresponding data link: Capture the received data at the MS / MR router, and confirm that the MS / MR router receives the register drop IP packet sent by router R3 or R4 (as shown in Figure 5 ), and record the time t2 at this moment. Then, the time taken for the "Map-Register drop" of the VHF radio's corresponding data link T1 = t2 - t1.

[0091] Calculate the time taken for the "Map-Register" of the L-DACS system's corresponding data link: Capture the received data at the MS / MR router, and confirm that the MS / MR router receives the register IP packet sent by router R6 (as shown in Figure 6 ), and record the time t3 at this moment. Then, the time taken for the "Map-Register" of the L-DACS system's corresponding data link T2 = t3 - t2.

[0092] Calculate the time taken for the "Map-Reply" of the L-DACS system's corresponding data link: Capture the received data at router R14, and confirm that router R14 receives the Map-Reply IP packet sent by router R6 (as shown in Figure 7 ), and record the time t4 at this moment. Then, the time taken for the L-DACS system's corresponding data link when updating the EID-to-RLOC path T3 = t4 - t3.

[0093] Through the above calculation process, the complete handover delay from the VHF radio's corresponding data link to the L-DACS system's corresponding data link is T = T1 + T2 + T3, thus realizing the handover delay test of the air-ground data link of the aeronautical telecommunication network based on the LISP protocol.

Claims

1. A method for testing the time delay of ground-to-air data link switching in an aviation telecommunication network based on the LISP protocol, characterized in that: The method comprises the following steps: S1. Building a test platform based on computers, routers and channel simulators; the test platform includes corresponding equipment and subnets of at least two sets of ground-to-air communication systems for implementing link switching operations; S2. For multiple types of routers in the test platform, configure the LISP protocol and the OSPF protocol accordingly to determine the preferred ground-to-air communication link and the alternative ground-to-air communication link; S3. Configure a channel simulator to simulate the signal transmission environment during flight; connect the corresponding equipment of each ground-to-air communication system to the channel simulator; S4, start the ground-to-air communication system corresponding to the preferred ground-to-air communication link, and simulate the process of the ground station sending test data to the aircraft through computer simulation; S5. The ground-to-air communication system corresponding to the preferred ground-to-air communication link is turned off, and the ground-to-air communication system corresponding to the alternative ground-to-air communication link is automatically switched and generates test data; S6. By means of router packet capture, the corresponding data packets when the preferred ground-to-air communication link is closed and when the alternative ground-to-air communication link is switched successfully are captured, and the ground-to-air data link switching delay is calculated.

2. The method for testing the time delay of ground-to-air data link switching in an aviation telecommunication network based on the LISP protocol according to claim 1 is characterized in that: The test platform built in step S1 includes an aircraft end, at least two ground-to-air communication systems, an ATN / IPS main network and an AOS / ATS server end; each ground-to-air communication system includes an airborne end and a ground station end connected through a channel simulator; the aircraft end and the AOS / ATS server end are both equipped with corresponding computers and routers, and the ATN / IPS main network is equipped with a router network; the aircraft end is connected to each ground-to-air communication system, each ground-to-air communication system is connected to the ATN / IPS main network, and the ATN / IPS main network is connected to the AOS / ATS server end.

3. The method for testing the time delay of ground-to-air data link switching in an aviation telecommunication network based on the LISP protocol according to claim 2, characterized in that: In each ground-to-air communication system, RF cables are used to connect the airborne end and the channel simulator, as well as the channel simulator and the ground station end. On the aircraft end, ATN / IPS main network and AOS / ATS server end, network cables are used to connect the corresponding computers and router networks.

4. The method for testing the time delay of ground-to-air data link switching in an aviation telecommunication network based on the LISP protocol according to claim 2, characterized in that: The aircraft end is constructed by a first computer and a correspondingly configured airborne router, and the airborne router is connected to the airborne end of each ground-to-air communication system.

5. The method for testing the time delay of ground-to-air data link switching in an aviation telecommunication network based on the LISP protocol according to claim 2, characterized in that: Each ground-to-air communication system has a ground subnet composed of subnet routers and boundary routers. The ground station end of each ground-to-air communication system is connected to at least one subnet router of the corresponding ground subnet; each ground-to-air communication system is connected to the ATN / IPS main network through the boundary router in the corresponding ground subnet.

6. The method for testing the time delay of ground-to-air data link switching in an aviation telecommunication network based on the LISP protocol according to claim 5 is characterized in that: The ATN / IPS main network is constructed by multiple main network routers and at least one MS / MR router; the MS / MR router is used as a LISP mapping server; the ATN / IPS main network is connected to the AOS / ATS server through the main network router.

7. The method for testing the time delay of ground-to-air data link switching in an aviation telecommunication network based on the LISP protocol according to claim 2, characterized in that: The AOS / ATS server is constructed by a second computer and a correspondingly configured border router, and the border router is connected to a main network router in the ATN / IPS main network.

8. The method for testing the time delay of ground-to-air data link switching in an aviation telecommunication network based on the LISP protocol according to claim 6 is characterized in that: In step S2, first configure the LISP protocol for the border router of the ground subnet and the border router in the AOS / ATS server in each ground-to-air communication system, and then configure the LISP protocol for the MS / MR router in the ATN / IPS main network; after the configuration is completed, set the EID addresses of the aircraft end and the AOS / ATS server respectively, determine and set the preferred ground-to-air communication link and the alternative ground-to-air communication link; at the same time, configure the OSPF protocol in the subnet router and the main network router.

9. The method for testing the time delay of ground-to-air data link switching in aviation telecommunication network based on LISP protocol according to claim 1, characterized in that: In step S3, the flight trajectory coordinate data of the aircraft used for the simulation test is generated by computer software used in conjunction with the channel simulator and imported into the channel simulator; the configuration parameters of the channel simulator are modified according to the ground-to-air signal transmission environment characteristics required for the simulation test, and then the channel simulator is connected to each ground-to-air communication system at the same time.

10. The method for testing the time delay of ground-to-air data link switching in aviation telecommunication network based on LISP protocol according to claim 2, characterized in that: In step S4, the test data is generated by the second computer configured in the AOS / ATS server, and the test data is transmitted through the ground-to-air communication system corresponding to the preferred ground-to-air communication link, so as to simulate the process of the AOS / ATS server sending data to the aircraft. Then, step S5 is performed, in which the ground-to-air communication system corresponding to the alternative ground-to-air communication link performs an automatic switching operation when the primary ground-to-air communication link is closed; In step S6, the time t1 of closing the ground-to-air communication system corresponding to the preferred ground-to-air communication link is recorded, and at the same time, the MS / MR router in the ATN / IPS main network is captured to record the time t2 of the data packet corresponding to the closing of the preferred ground-to-air communication link, and the closing delay T1=t2-t1 is obtained; Then, when the alternative ground-to-air communication link is switched successfully, the MS / MR router in the ATN / IPS main network is captured, and the corresponding data packet time t3 when the switching is successful is recorded, and the first switching delay T2=t3-t2 is obtained; then, when the AOS / ATS server receives data after the switching is successful, the border router in the AOS / ATS server is captured, and the corresponding data packet time t4 when the data is received is recorded, and the second switching delay T4=t4-t3 is obtained; Thus, the switching delay T=T1+T2+T3 of the preferred ground-to-air communication link switching to the alternative ground-to-air communication link is calculated.

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