I don't know what those 4 letters are...and depending on how I interpret them, you can end up in a multitude of "interesting" circumstances...
ISI by no means will guarantee you that. Period. There were some discussions about that already. But, in the same time... as far as means and their plans go, they will try to keep the service running as long as possible - at least, that's how I understand various answers given by ISI staff.
Does rf2 support LAN races? If so I believe there are services that use this to enable online play with older games.
No it doesn't. I guess to prevent people with ilegal copies from participating in any sort of multiplayer. This also means if you can't connect to ISI's server for what ever reason (i.e. their servers are down for maintenance, they got hacked and don't want to run on a compromised system, you're having DNS problems, ...) you can't participate in any sort of multiplayer too. Some people here including me had connection issues that went away after more than a week with a gray multiplayer button... Link No one knows what it was but i guess a faulty or overloaded router as the problem was regional and ISI said they haven't had any problems during that time. So you have to think about 3 factors (your connection, ISI and all the network equipment in between which is a lot) and not just ISI's servers. If it's something in between you and ISI then you can only pray for it to be fixed soon no matter how good ISI is dealing with high availability.