TCP was part of the initial network transmission program that eventually gave way to the Internet Protocol used in modern networking. TCP is widely used for its reliability, ordered nature the packets are processed in a fixed sequence, not just as they arrive , and error correction. TCP is used for a ton of things, like email, file transfers, and any other operation where ordered, error-free data is more important than pure speed.
In network diagnostic software like PingPlotter, TCP is best used when testing specific situations where a TCP-like segment fails or struggles to reach its destination. A great example is with FTP. This means UDP datagrams can be sent without establishing a connection between two devices, allowing them to be sent without consideration for rate or sequence.
For UDP, the primary focus is speed. Since UDP datagrams are coordinated by the application and not the protocol, they can be received and processed as they come.
This is critical for things like video streams or VOIP, where processing info as fast as possible is more critical than reassembling the data in perfect order.
In PingPlotter, using UDP to test things like livestreams or other time-sensitive applications can give you a better idea where your data is being held up. If the connections are good and the target computer is up, a good return packet will be received. PING can also tell the user the number of hops that lie between two computers and the amount of time it takes for a packet to make the complete trip.
Additionaly, an administrator can use Ping to test out name resolution. If the packet bounces back when sent to the IP address but not when sent to the name, then the system is having a problem matching the name to the IP address. If this takes an extended period of time, it is indicative that something may be wrong. The modern Ping program was written by Mike Muuss in December, , and has since become one of the most versatile and widely used diagnostic tools on the Internet.
Muuss named his program after the sonar sounds used for echo-location by submarines and bats. Just like in old movies about submarines, sonar probes do sound like a metallic "pingggg". The Ping program works much like a sonar echo-location. The IP address Therefore, a ping to that address will always ping yourself and the delay should be very short. You can perform a ping on a Windows computer by opening an MSDOS window and then typing "ping" followed by the domain name or IP address of the computer you wish to ping.
You can list the available options with the command "ping -? If you can't use Ping from your own computer because of a firewall or other restriction, or want to do a ping from another location than your own, you can use one of the following web sites:. These pings are sent from the computer hosting the web site, not from your computer, so the times returned reflect the time for communication from that web site, not from your computer.
However, they are useful to determine if an address can be reached from different places around the Internet, and to determine how long it takes to reach one site compared to others from most sites. Data will pass back and forth from one to the other until the session times out or, in this particular case, the maximum hop limit is reached. Note : You will often see this if the end user has been 'wall gardened'. A 'walled garden' refers to a browsing environment that controls the information and Web sites the user is able to access.
This is a popular method used by ISPs in order to keep the user navigating only specific areas of the Web. This is often for the purpose of shielding users from information, such as restricting children's access to unsuitable material. Ping is a network utility used to see if the end user can reach other devices connected to the internet. When using Ping, always test a few different sites to see if it is just one site or all sites.
The program reports errors, packet loss, and a statistical summary of the results. In the following examples, the Ping command was used to check the connection to device The following example shows the screen display after a successful ping attempt, where four packets were sent, and four packets received. A ping result, where the target device is not responding, or there is a connection issue, will look like this:.
Note : A result like this does not always mean the device is not online or working correctly. Many devices have ICMP ping responses disabled for security or service reasons. So even if they are up and running it will appear as if they are unreachable.
Unfortunately, a sample set of four pings is not suitable for detecting packet loss, so we need to run a longer test. This is done by adding the —n option flag, followed by the number of pings you want performed, as in the following example; ping —n This will ping the target times, and fill the screen with every ping sent. We don't need to view every ping, just the final result, which will look like this:.
As you can see in this test we dropped two packets but, due to the large sample size, this is negligible and is well within working parameters. We judge packet loss on a case by case basis. If significant loss is seen, we require some further testing using either PathPing or the MTR utility.
MTR probes routers on the route path by limiting the number of hops that individual packets may traverse, and listening to responses of their expiry. It will regularly repeat this process, usually once per second, and keep track of the response times of the hops along the path.
Please check the name and try again. If the end user is able to ping an IP address, but can't ping a domain name, such as bbc. This network utility is a more advanced version of the Ping tool, which performs a ping to each hop along the route to the destination unlike Ping, which just pings from the originating device to the destination device. It is extremely useful in diagnosing packet loss, and can help with diagnosing slow speed faults.
The advantages of PathPing over Ping and Traceroute are that each node is pinged as the result of a single command, and that the behaviour of nodes is studied over an extended time period, rather than the default ping sample of four messages, or default traceroute single route trace. The disadvantage is that it takes a total of 25 seconds per hop to show the PathPing statistics. In the following examples, the PathPing command was used to check the connection to device In the example, there were five hops along the route from the origin, At each hop, packets were sent and no packets lost.
The example illustrates some of the different results you might encounter. Look at each of the hop results, and what they signify. In the example, we will focus on hops 1, 3, 4, and 9. A result showing loss from the first hop indicates the likely cause to be the originating end user's router, and would be reflected with the IP address of the router such as In this instance, check, and if necessary replace, the router, then retest.
If the loss is evident from a hop after the originating router most likely hop 2 onwards , then the issue should be raised to the service provider.
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