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What does TraceRoute mean? I believe that many inexperienced people are at a loss about this, so this article summarizes the causes and solutions of the problem. Through this article, I hope you can solve this problem.

The traceroute (tracert in Windows) command uses the ICMP protocol to locate all routers between your computer and the target computer. The TTL value can reflect the number of routers or gateways that the packet passes through. By manipulating the TTL value of the independent ICMP call message and observing the abandoned return information of the message, the traceroute command can traverse all the routers on the packet transmission path.

Principle

The program realizes its function by increasing the value of survival time (TTL). Every time a packet passes through a router, its survival time is reduced by 1. When its survival time is 0, the host cancels the packet and sends an ICMP TTL packet to the sender of the original packet.

The first three packets sent by the program have a TTL value of 1, the next three are 2, and so on, it gets a series of packet paths. Note that IP does not guarantee that every packet takes the same path.

Define

It consists of tens of thousands of local area networks and millions of computers all over the world, and communicates between networks through the TCP/IP protocol used in heterogeneous networks. In the Internet, information is transmitted from one end to the other through the transmission media and devices (routers, switches, servers, gateways, etc.) of many segments of the network. Each device connected to the Internet, such as host, router, access server, etc., generally has a separate IP address. Through Traceroute, we can know the path of information from your computer to the host on the other side of the Internet. Of course, each packet from the same starting point (source) to a certain same destination (destination) may take a different path, but basically, most of the time the route is the same. In UNIX system, we call it Tracert in Traceroute,MS Windows. Traceroute measures how long it takes to send a small packet to the destination device until it returns. The Traceroute of each device on a path is tested 3 times. The output includes the time of each test (ms) and the name of the device, if any, and its IP address.

Parameter description

Tracert [- d] [- h maximum_hops] [- j computer-list] [- w timeout] target_name

The diagnostic utility determines the route to the destination by sending Internet Control Information Protocol (ICMP) response messages with different time to live (TTL) to the destination. Each router on the path reduces its TTL value by at least 1 before forwarding the ICMP echo message, so TTL is a valid hop count. When the TTL value of the message is reduced to 0, the router sends back ICMP timeout information to the source system. Tracert can determine the route by sending the first response message with a TTL of 1 and incrementing the TTL value by 1 each time in subsequent transmissions until the target responds or the maximum TTL value is reached. The router can be determined by examining the ICMP timeout (ime Exceeded) information sent back by the intermediate router. Note that some routers "quietly" discard time-to-live (TLS) expired messages and have no effect on tracert.

Parameters.

-d

Specifies that the address is not resolved to the computer name.

-h maximum_hops

Specifies the maximum number of jumps for the lookup target.

-j computer-list

Specifies that the source route is loose in computer-list.

-w timeout

Waits for the number of milliseconds specified by timeout for each reply.

Target_name

The name of the target computer.

After reading the above, have you mastered the method of what TraceRoute means? If you want to learn more skills or want to know more about it, you are welcome to follow the industry information channel, thank you for reading!

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