What happens when we type http://www.google.com

What happens when we type www.google.com . Can anyone please provide me the step by step process.

Pradeepvu,


In a very compact step-by-step, here's the procedure. Let's assume you typed: www.cisco.com :

1) Your PC will need to resolve www.cisco.com to an IP address. It will therefore need to send a query to your DNS server ( usually your ISP's DNS).

2) The Pc constructs a DNS query packet with a destination IP address equal to your DNS server and a destination MAC address of your router (gateway).

3) The DNS query process begins. This is explained in much detail on our DNS page: www.firewall.cx/dns-resolution.php

4) Once your PC (web browser application) receives the IP address of the destination web server, it will construct a HTTP GET request and send it to Cisco's web server.

5) Cisco's Web server will reply and start sending your application the necessary data using TCP sessions. These sessions are again explained in great detail in our TCP protocol analysis: www.firewall.cx/tcp-quick-overview.php

6) The application will start to draw and present the website on your screen.

Of course, between all the above data exchanges, the packets that run in your local network have their destination and source mac addresses set to the relevant local machines (your pc and router).

Hope that helps!

Cheers.

Just whatever you do, don't type google into Google...you can break the Internet

Source:

KiLLaBeE - hahaha good one mate !!!! 50 points to KiLLaBeE!

Chris,

I agree with everything you said so I'm just going to copy it and add to it.

In a very compact step-by-step, here's the procedure. Let's assume you typed: www.cisco.com :

1) Your PC will need to resolve www.cisco.com to an IP address. It will therefore check need to your computers local host file and if it doesn't find the IP address (which it generally does not unless you put it there) it will send a query to your DNS server ( usually your ISP's DNS).

Your host file can be located at: C:\winnt\system32\drivers\etc
if you are on a windows system. It looks like this:



After checking the host file and finding nothing USER enabled DNS settings will be checked. If none are found it defaults to your ISP'S DNS service.




2) The Pc constructs a DNS query packet with a destination IP address equal to your DNS server and a destination MAC address of your router (gateway).

3) The DNS query process begins. This is explained in much detail on our DNS page: www.firewall.cx/dns-resolution.php

4) Once your PC (web browser application) receives the IP address of the destination web server, it will construct a HTTP GET request and send it to Cisco's web server.

5) Cisco's Web server will reply and start sending your application the necessary data using TCP sessions. These sessions are again explained in great detail in our TCP protocol analysis: www.firewall.cx/tcp-quick-overview.php

6) The application will start to draw and present the website on your screen.

Of course, between all the above data exchanges, the packets that run in your local network have their destination and source mac addresses set to the relevant local machines (your pc and router).

This is really helpful but can anyone tell me what exactly happens in transport and network layer when GET request is sent