connection with the servers?

thedrama

There is something i didn't figure out somehow regarding servers. Lets imagine two different examples. First, connecting to gmail,hotmail etc.. second, connecting to a forum like this.

1) For the first example, lets say the domain name is gmail.com and i mean, 'a website'. However, the purpose of connecting to gmail is to contact for 'mail exchange.' So, after i typed gmail.com and got the page on my browser(client) , is this said a connection to HTTP server or a mail server?

2) For the second example, i typed techexams.net then received the main page on my browser again. This indicates an HTTP connection again. Nevertheless, titles topics and other stuff are said to be 'files' . In this way, did i set up a connection to
an HTTP server or a file server?

lordy

The type of connection your browser creates is always indicated by the protocol prefix. E.g. http://, https://, ftp://, etc.

If you do not provide a prefix, the default is HTTP. So in your examples you are only using HTTP.

Everyone

In both your examples you're connecting to a web (http) server.

In example 1, the web server is acting like a mail client on your behalf, it connects to other servers on the back-end to retrieve your mail. You only ever connect to the web server.

For example 2, again the web server you're connecting to is just the front end piece. The content on a forum like this is typically stored in a database. The only "files" you access are the HTML, PHP, ASP, or whatever language the website runs off of. Only a web server knows how to present these types of files to your web browser. If you accessed the same files off a file server (i.e. a file share on a server), they wouldn't function properly in your web browser, but you could open them up in an editor to make changes to them in order to change their appearance or behavior when accessed via the web sever.

thedrama

Well, then, how about the network protocols used during both situation?

I mean, i initiated a connection(connection request)to a web server across TCP through HTTP and after that did i make use of SMTP cos i requested mail? (for the first)

For the second example, the first protocol is same. However will the second protocol be FTP?

Everyone

YOU only use HTTP to the web server. It doesn't magically switch over to another protocol. Web traffic is web traffic is web traffic.

Go read up on your ports and protocols. Short answer to both is NO you did not.

RobertKaucher

thedrama wrote: »

Well, then, how about the network protocols used during both situation?

I mean, i initiated a connection(connection request)to a web server across TCP through HTTP and after that did i make use of SMTP cos i requested mail? (for the first)

For the second example, the first protocol is same. However will the second protocol be FTP?

You are confusing intention (getting your email) with reality (connecting to a web server front end that uses some other format to connect to data on the back end).

When you make a request to gmail.com you are sending an HTTP GET request (I am simplifying the next steps so as to be instructive) the web server (assuming you are authenticated) then contacts whatever service on the backend it uses to find your email messages. This could be a MySQL or other database, it could be any sort of system that can store data - it does not need to be a mail server. The database then returns the the data to the web server which composes the webpage used to represent your "inbox". The web server sends your browser back this page.

Now when someone sends you an email at your gmail account an SMTP server receives the message and routes it to another application which parses it and then stuffs it into the data store. It would be inefficient to compose an HTML based web app that used something like JavaScript and AJAX to access an SMTP/POP3 server directly as a client. You would use some sort of server side technology for that.

dustinmurphy

I want to add that in general... EVERY webpage you hit is a file on a server of some sort. Some application servers convert coding to HTML (i.e. ColdFusion) and display the page as HTML, however each page is a file of some sort. Pages such as the forum are dynamic, which means it pulls data (posts, etc) from a database, and displays the data.

As has been said... when YOU browse to a website, you're either using HTTP or HTTPS. Your browser doesn't know how to speak SMTP. It understands FTP, but FTP doesn't have any styling. It just shows directories and files.... not stylized content. The servers do many things on the backend, like was said ... the backend servers receive the SMTP requests and parse the emails and store them in a data store (most likely a database), then when you access the front end via HTTP, it displays the information to you. When you send an email from GMAIL, your web browser doesn't setup an SMTP connection (it doesn't know how)... but the coding on the website has a backend process that has an SMTP relay server that will relay the mail to your intended recipient.

MentholMoose

Install Wireshark and you can see for yourself exactly what is sent/received.