How to send strings between two computers?

Question

Possible duplicate:
New to Delphi Network!

I would like to learn how to get two machines to exchange data, send and receive simple strings. Machines can be on the same local network - or not. I'm talking about something more or less similar, as you saw in the chat. I understand Delphi, but I know absolutely nothing about things like TCP, sockets, ports, etc. Where would you advise me to learn this? ... I know how to use Google, but to be honest, I'm not quite sure where to start the search!

Thanks, as always.

Answer 1

to learn how to communicate through sockets, the best IMO articles:

http://www.felix-colibri.com/papers/web/socket_programming/socket_programming.html
http://www.felix-colibri.com/papers/web/delphi_socket_architecture/delphi_socket_architecture.html (it explains to you at the socket level how everything happens)

and

http://delphi.about.com/od/networking/l/aa112602a.htm

as a starter for this kind of thing, I suggest you also http://delphi.about.com , which is a very good resource.

Once you understand the concepts well, you can go to the next level and use Indy or any other components that make your life easier.

Answer 2

Delphi has been shipped with Indy for several years as part of the initial installation. If you go to the Indy download page (linked), you will find a link to several demo applications, one of which is a chat demo.

You did not specify which version of Delphi you are using, so the demos may or may not need minor changes. If you cannot understand them, you can post specific questions about the problems here (if they are no longer there).

Edit: It seems they have refused to demonstrate the chat in recent versions. There's a full chat application (with code) on Delphi.About that can help (along with a few other Indy demos and articles).

Answer 3

Start with the OSI Model (7 layers) and then read more about each layer, in particular Ethernet in the physical layer , TCP and UDP on the transport layer and possibly HTTP on the application layer .

The Indy library encapsulates things very well at the transport level with classes such as TIdTCP , and at the application level with classes like TIdHTTP .