What is ping

07/09/2015 01:00

Ping is one of the most useful tool for network Administrators, that is used to check if a host is reachable on an IP Network. Ping is a command line tool which is exists almost on any computer.

It operates by sending ICMP ( Internet Control Message Protocol ) "echo request" packets to the target device and waits for ICMP response, if it received ICMP response packets then means that the target device is accessible and alive but some devices are blocking this kind of packets so is impossible to determine if this device is accessible by using this tool. Ping also measures the time which takes the packet to go to the target and come back, this is called round-trip time and indicates the latency of the route which has the packet follow.

 

Ping

examples

You can use ping tool to check if your computer has internet access by pinging a device on Internet eg the google's web server.

Open the Command Prompt:

"Start->Accessories->Command Prompt"

Type the following command:

ping www.google.com

If your internet connection is ok you will get something similar to the following

Microsoft Windows XP [Version 5.1.2600] (C) Copyright 1985-2001 Microsoft Corp.

C:\Documents and Settings\what-ipaddress>ping www.google.com Pinging www.google.com [74.125.132.106] with 32 bytes of data: Reply from 74.125.132.106: bytes=32 time=67ms TTL=44 Reply from 74.125.132.106: bytes=32 time=67ms TTL=44 Reply from 74.125.132.106: bytes=32 time=69ms TTL=44 Reply from 74.125.132.106: bytes=32 time=67ms TTL=44 Ping statistics for 74.125.132.106: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds: Minimum = 67ms, Maximum = 69ms, Average = 67ms

Otherwise you will see a "Request timed out" or "Destination host unreachable" message.