many thanks for that, for my understanding, if we are using http web page, how come the traffic is not sent across port 80 then ?, or is it using both ? please help

Car, it all depends on the IIS app server and what ports it is configured to respond to, for example I have seen IIS developers configure a particular Webserver to respond to different tcp port numbers for various purposes and different access, so you could have an IIS server listening not only on default port 80 but in addition to other tcp ports of their choice, which then requires the source to especify http:\\1.1.1.1:5050.

You may have different applications listening on different ports, for exmaple

monitoring software, ciscoworks, etc.. listens to different ports and not the default 80 port.

HTH

Jorge

As I said, the primary use for multiple ports is application selection - I would expect a server to respond on 80 as well, but it may well be a different response IYSWIM.

A single server may well run multiple applications, and those applications can potentially be selected in a number of ways.

I will assume that we are talking purely about browser-based applications.

If a single server is running payroll, scheduling and intranet as an example, there are three primary ways the server can handle the selection.

The first is by name. eg payroll.mycompany.com, sched.mycompany.com www.mycompany.com. DNS would resolve these to the same IP address, but the browser would be configured to direct requests for those names to different bits of the server.

The next bit is by specifying further into the URL - www.mycompany.com/payroll mycompany.com/scheduling and www.mycompany.com/intranet as an example.

The third way i by using the port. This allows a totally different application can be listening on the port - it means you can even run apache, IIS and any other at the same time, and say Oracle can handle clients directly - www.mycompany.com would be intranet www.mycompany.com:8008 may be scheduling www.mycompany.com:5000 for payroll etc - the numbers to a degree to not matter - they are just a way of selecting.

Think of it as being like extention numbers when phoning a building - an extension number for payroll, an extension for scheduling.

P.

thanks for that, lastly, all i need to know is that if you type the port number at the end, are we still talking over http ? as i thought http is port 80 ? or if you specify port number at the end like you say it only talks on that port , or is it both ?

If a port number is specicifed, it will still be using HTTP, but on port whatever. The first bit of the URL indicates it is http (the http: bit) If no port is specified, the browser will assume port 80, but if a port is specified it will use that instead, not as well as. HTTP is the application - ie what we do with the data being sent) the port number is simply the port to connect on.

so i gather http is not always port 80, it can be many other ports, so even though i type in http:// with say :50 at the end it will not use port 80 it will use port 50 but is still http ?

Exactly!

80 is the well knwn port for HTTP, it is not mandatory.

yes, it is still http, because you are specifying HTTP:// in front of the URL. By putting the :50 at the end of the URL, you are specifying to use port 50.

HTTP is the communications protocol

TCP is the transportation protocol

Port 80 is the default port # HTTP uses

:)

-brad

www.ccbootcamp.com

(please rate the post!)