what is ping?

Sound like it is something from out of space. There are many meanings to what ping is. This website will be about computer networking ping. If this is not what your looking for then here is a friendly link to all the other definitions of ping.

What is IP?

IP stands for Internet Protocol. All devices such as PCs, website servers, switches and routers have an IP address to communicate over the internet. Think of an IP address as a postcode or zip code, without the postcode or zip code, we cannot receive our mail through the postal system. An Internet Protocol address is a 32-bit number, which looks similar to 217.17.21.17 (each 8 bit number can start from 1-255). I do not want to go into to much detail, but hope you get the idea that all devices on the internet will have an IP address.

What is ICMP?

ICMP stands for Internet Control Message Protocol. ICMP was created to send test messages across an IP network. Sending these messages would let you know if a device like PCs, website servers, switches and routers are contactable over an IP network. Ping uses ICMP to contact other devices on the IP network.

The nature of ping.

Many people in the IT world will recognise ping as a network utility to test whether or not a device such as a router, server or switch is contactable. The way this works is the computer or device will generate an ICMP packet that is sent over the local network or internet. The ICMP packet will find its way across the network by having a source and destination IP address. When the device receives this information it then sends a reply saying “yes, I am here”. As I work for an ISP (Internet Service Provider) myself this is an essential tool to help do my job. Ping is used a lot in IT and network troubleshooting.

Ok, still don’t understand what ping is?

Right I guess some of you are not technical that is why you are on this site. The best analogy that I can think off for ping is; say you are at home and you want to get a newspaper from the shop, the shop is about 3 miles away, so you get in your car. It takes about 10 mins to get to the shops, 2 mins to buy the paper and another 10 mins to get back to your house. The total journey time is 22 minutes. The same concept applies ping. The packet is generated by your PC and sent into the internet cloud, and the destination (being another PC, server, switch or router) receives this ICMP packet processes it and sends it back with an ICMP response.

Obviously depending where you are sending a ICMP packet around the world will tell you how much delay you will get in your response times. If you pinging within your country and it has a good internet infrastructure response times should be quicker than if your pinging to a different country as the ICMP packet has to travel a greater distance.

Right I sort of get ping, how do I do it from my Windows PC?

Enough talk about ping. First we need to get a command prompt open. If your using Windows, most versions have the “run” function.

So click on Start (or Windows Symbol Left hand side) > Run > Type cmd in the box then hit OK or Enter.

A black screen should appear before you. Now we need to find an IP address to ping. You can find a website address to ping to see if the web server responds back with an ICMP packet. In the example below, we can see a response from www.cisco.com. Simply type ping www.cisco.com (or any other website you want), hopefully you will see four lines of response saying the Cisco Webserver is there and how long is took (ms = milliseconds). In this example the four ICMP packets took around 125ms to get to the Cisco webserver and back to my PC.

C:\Documents and Settings>ping www.cisco.com

Pinging e144.cd.akamaiedge.net [84.53.164.170] with 32 bytes of data:

Reply from 84.53.164.170: bytes=32 time < 125ms TTL=128
Reply from 84.53.164.170: bytes=32 time < 135ms TTL=128
Reply from 84.53.164.170: bytes=32 time < 125ms TTL=128
Reply from 84.53.164.170: bytes=32 time < 125ms TTL=128

Ping statistics for 10.163.2.169:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 125ms, Maximum = 135ms, Average = 126ms

Note: Some websites you might not be able to ping for security reasons, and get a “Request time out” message. This is due to a Firewall being present which blocks ICMP packets. A firewall is a security device that prevents attacks or viruses entering your computer network and often can be standard practise that firewalls blocks ICMP packets.

Conclusion about ping

I hope I have given some insight into ping for some people who are not technical. There are more advanced functions of ping that you can use. You can research more advanced techniques of ping at our sister site “How to Ping” (coming soon). I wish you well in your first step into Internet networking by utilising the ping function.