What Are The Results When You Visit A Web Web site?
Time For Many Alphabet Soup
Whenever you type an address into your web browser, or click on a link in a web site, you are making a demand for a particular document. Managed by the Hyper Text Transfer Protocol (HTTP), your request is sent over the Internet to the server that contains the file you want. Assuming all goes well, the server can respond by sending the file, often a web page composed of graphics and text.
Exactly what is HTTP? It's the main Internet Protocol (IP) suite, and can be used by a 'client,' including a browser, to establish a reference to the server that hosts a particular site. This engaging http://michaeldoven.com link has numerous forceful lessons for the purpose of it. The host displays TCP port 80 because it waits for incoming requests.
Associations on the net that allow 2 computers to switch information are made from the Transmission Get a handle on Protocol (TCP). TCP is prepared to properly transmit information to its destination, and to identify the computer. To get further information, please consider having a gander at: www.michaeldovenphotography.com.
Machine To Browser -- Behind The Scenes
A few TCP ports can be found with standard uses. For case, TCP Port 21 is normally reserved for FTP (File Transfer Protocol) for uploading and downloading files. Port 80 is usually useful for HTTP.
In the event the server receives a request chain on TCP port 80 in-the type of GET / HTTP/1.1 it will send an answer code, depending on perhaps the requested web page is available or not. A normal request will look like this:
GET /faq.html HTTP/1.1
It is a request for the site 'faq' to the host site 'my-website.' The 'host' should be specified to tell apart between websites which are managed on shared servers. If faq.html is available, the server will respond some thing like:
HTTP/1.1 200 OK
Date: Mon, 12 October 2005 22:38:34 GMT
Server: Apache/1.3.27 (Unix) (Red-Hat/Linux)
Last-Modified: Wed, 08 Jan 2003 23:11:55 GMT
... followed by the actual website.
How Data Gets Where It's Going
The very first line above, HTTP/1.1 200 OKAY, means that the requested website is available. Other rules are often returned. For instance, the code 404 means the server can't discover the requested page.
When found, the website is sent via TCP as a group of data packets, each with a header that describes its location and its order in the data stream. The many packages may take different routes to reach their destination.
Each is sent through a modem, which polls other routers nearby. If a connection with the initial switch is unavailable, the info is going to be delivered through a different one. This permits the data to attain its destination as quickly as you can.
What Happens When I-t Gets There
Once the browser receives the data, it sends back an acceptance. This insures that all the packages have been received within a particular time. Or even, they'll be re-transmitted by the machine. TCP also checks to be sure the info is undamaged.
The data is then reassembled in-the proper order, due to the sequence number of each data packet.
And Presto! The internet page appears on your screen, often in a matter of seconds..