1. Now they all connect to the IRC server "server.com" except they are located in different areas correct?
No. The two servers both have hostnames which happen to be subdomains of server.com (ie.
something.server.com), but that does not in any way mean that they connect to a server using the hostname server.com (although the owners must have some affiliation with it to be using a subdomain). To answer the second part of that sentence: yes, they could very well be in different locations.
2. If they are located in different areas how exactly do they share information. I remember tomato king did some minor explaining to me. He was really nice but I still failed to understand it.
They are connected to each other, in basically the same way that you or I or any other client would connect to one of those servers. The difference being that both servers have been specifically configured to treat certain connections (identified usually with a password and sometimes accepted only from certain domains or IP addresses) as servers, which means they allow certain commands that would be ignored if an ordinary client connection sent them.
3. He said that the servers often share information every 24 hours or so. What about nickserv chanserv etc. And even chatting. When I type does the server relay that to other users on another location of the server. EG I am on dallas, does london read my text I sent.
I don't know anything about sharing information every 24 hours, AFAIK all information is shared in real-time, but then again I haven't been a network administrator on a *real* IRC network before so I couldn't say for sure that tehre isn't some information that gets sent only at certain intervals. Nickserv, Chanserv, and any other services bots are just users (often connected to their own separate server) that have certain flags set so that they can 'see' what's happening in all channels, and can do other things that regular connections cannot. As for your text, it is only seen by servers which it has to pass to/through in order to be sent to everyone you want it to be sent to. For example:
Let's say there are four servers named
A,
B,
C, and
D connected like this:
A[color:green]--B
--C
--D[/color]
Let's say you're connected to server
A, and you're on a channel with two other users: 'Joe' connected to
A, and 'Arnie' connected to
C.
If you send a message to the channel it will be sent to
A first of all (since that's where you're connected), relayed back to Joe since he's also on
A, and also sent
through B to
C, which is where Arnie is. However
D will never see the message. The same thing happens with private messages; it will only be sent to the servers which have to see it in order for all targets of the message to receive it.
4. How much does this type of operation and set up cost?
It depends. If you're only running a small server or network with perhaps just 50 or less regular users you might get away with using your home connection as a server (assuming you have a static IP and broadband). If you're planning on hundreds or perhaps thousands of users then you'll need to get hosting which supports IRCds. I don't know the pricing offhand, but I do know it can get very expensive.
5. Are there any problems and issues. What type of software is required. Is it really hard and is it recommended. I have seen quite a few servers use this method.
The only software required is an IRCd, many of which are completely free. Services are usually separate, but are often free also. Hard? Depends on your level of experience/knowledge of networks, both with IRC and in general. Recommended? Only if you're willing to put in time and probably money with little chance of getting much in the way of thanks. Not sure what you mean by 'method'.
6. When connecting to a server it is best to connect to one closer to your location right?
Yes, it usually is. However if you connect to a local one and it seems lagged you can always try one further away to see it it's better. Typically you'll get a decent enough connection with any IRC server anywhere in the world anyway, it's just 'better' to use one closer to home if possible.
