 We have our three Linux machines inside virtual box and set up in an internet where we have a client and router on one land NetA with network address 192.1681.0 and the router and server on a second land NetB 192.1682.0. Let's have a look at PIN communicating between two nodes to test for connectivity and test delay and So I'll use PIN to communicate between the client and server noting the server has address 192.1682.22 and the client 1.11 and we need to go via the router so I'll go to my client and We'll use PIN. PIN triggers Internet control message protocol messages to be sent ICMP messages of a certain time and The simple way to use PIN is to specify the destination. You want to PIN 2.22 in this case. I'm on the client and what it does is It starts this PIN which by default every one second Sends a ICMP echo request to the destination and the destination will receive that and send back an ICMP echo reply and For each second each reply we get PIN prints out a line here showing us some details And it keeps doing that every second so every one second It's continuing it's sending an echo request to the server and the server is getting back a response It'll go forever to stop at control C And when we do control C it lists some Statistics some summary statistics at the end which we'll have a look at in the moment Sometimes we don't want to go forever so we can specify our count with a minus C option. Let's PIN three times to the server And it stops in this case after three PINs So just looking at the output here. What is it saying? The top line is a summary of what's happening We're doing a PIN to 192.1682.22 if we had a domain name like we're trying to PIN www.google.com it would show the domain name and the IP address here This is something about how much data we're sending so what PIN does is it's not about communicating data But the echo request includes some dummy data in it and in this case 56 bytes of dummy data Creating an echo request of total size of 84 bytes There's some header information and then we send that request every one second and in this case we get three replies and a line was printed each second but each reply received We received 64 bytes from the server The ICMP echo reply was containing sequence number one The time to live or TTL Indicates the number of routers we go through in this case the initial value was 64 Every time this message go via router. It's decremented by one So 63 means this message has passed by one router and The time is the roundtrip time the time from when my client sends until it receives the reply So to get there and back 0.276 milliseconds then at depth again and again the summary statistics Number of packets transmitted received No packets lost The total time it took to do that PIN and Then the roundtrip time, which is these three values the min Average maximum and essentially mean or standard deviation in this case the minimum was 0.276 milliseconds max 5.847 The average is calculated in a standard deviation So we can get some summary statistics when we have more multiple PINs Some other options we can specify the interval by default every one second We can set it to send every two seconds You see a slight more delay there every two seconds it prints out a result so we can change the interval using the minus I option and We can set the size of the data being sent the 100 So send three PINs a count of three interval of two seconds two seconds between each PIN and The size of the data a hundred bytes instead of the default 56 bytes and a 108 bytes come back because it's a hundred bytes plus eight bytes of extra header information and there are other options with PIN If you see the man page, you can see the many different options that PIN has so PIN Can be used to test network connectivity if we can ping another node then or another computer that it means We generally have basic connectivity with that IP connectivity with that computer So when I ping from client to server, I know I can communicate with server It tells me on the path between the source and destination the number of routers I've passed through based upon the time to live the TTL. I saw 63 I knew that was one less than 64 meaning one router get passed by it And importantly, it tells us the time to get from client to server and back the round trip time So it can give us some information about delay So use PIN for testing network connectivity connectivity and and measuring delay You