define

Ping is a computer networking tool that tests whether a packet can reach a specific host over an IP protocol. Ping works by sending an ICMP request echo packet to the target host and waiting for the echo response packet to be received. The program will estimate the packet loss rate (packet loss rate) and packet round-trip time (network delay, round-trip delay time) according to the time and the number of successful responses.

Numerical meaning

In Ping Baidu.com on Windows, the following screenshot is shown:

byte

The size of each packet.

time

The time of the round trip. As shown in the screenshot, after ping, four packets were sent, and the corresponding time was 39ms/37ms/38ms/38ms respectively, which was relatively stable. That is, there is no network jitter.

TTL

Time To Live (TTL) is a computer networking term that refers To the maximum distance (hops) that a packet can travel while passing through a router. Each time a packet passes through a router, its number of lives is subtracted by one. When the number of survival is 0, the router will cancel the packet forwarding. In the case of IP network, an ICMP TTL packet will be sent to the sender of the original packet to inform the hop point limit has been exceeded. It is designed to prevent packets from being unable to reach and depleting network resources due to the infinite loop caused by incorrect routing table.

The TTL value is not the smaller the better, instead, the larger the better. Because the higher the TTL value is, the fewer routers the packet is sent through, and the faster it will arrive at the destination.

The TTL default value is not the same in different operating systems.

Here’s how to view Windows 10 Pro:



So the default decimal value is 64.

It’s called ping baidu.com. It’s 64-51=13 routes.