When a computer in New York wants to send a piece of data to a computer in England, it must know the destination IP address that it woud like to send the information to. I know you are getting confused, but I promise I will explain this in very basic terms so that you can understand this concept.
Using this method, the computer sending the data connects directly to the computer it is sending the data it to, and stays connected for the duration of the transfer. With this method, the two computers can guarantee that the data has arrived safely and correctly, and then they disconnect the connection. This method of transferring data tends to be quicker and more reliable, but puts a higher load on the computer as it has to monitor the connection and the data going across it. A real life comparison to this method would be to pick up the phone and call a friend.
You have a conversation and when it is over, you both hang up, releasing the connection. Using this method, the computer sending the data packages the information into a nice little package and releases it into the network with the hopes that it will get to the right place. What this means is that UDP does not connect directly to the receiving computer like TCP does, but rather sends the data out and relies on the devices in between the sending computer and the receiving computer to get the data where it is supposed to go properly.
This method of transmission does not provide any guarantee that the data you send will ever reach its destination. On the other hand, this method of transmission has a very low overhead and is therefore very popular to use for services that are not that important to work on the first try.
A comparison you can use for this method is the plain old US Postal Service. You place your mail in the mailbox and hope the Postal Service will get it to the proper location. Most of the time they do, but sometimes it gets lost along the way. Lets move on to the next section where we can describe the concept of ports better. As you know every computer or device on the Internet must have a unique number assigned to it called the IP address. This IP address is used to recognize your particular computer out of the millions of other computers connected to the Internet.
When information is sent over the Internet to your computer how does your computer accept that information? An easy way to understand ports is to imagine your IP address is a cable box and the ports are the different channels on that cable box. Labels: logical ports , network ports , ports. Newer Post Older Post Home. Subscribe to: Post Comments Atom.
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Learn how your comment data is processed. By ICANN there are three categories for ports: From 0 to — well known ports assigned to common protocols and services From to — registered ports assigned by ICANN to a specific service From to 65 — dynamic private, high ports range from 49, to 65, Can be used by any service on an ad hoc basis. Ports are assigned when a session is established, and released when the session ends. Like this: Like Loading Namespaces Page Discussion.
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