Heh... interesting reply.
Anyhow, to give you an understanding of what you are seeing, here's what is happening.
Some people who serv anything (doesn't have to be warez as is suggested above) either have a firewall or a router which they cannot configure either because they don't know how, or aren't allowed to (parents, school, etc), or some other reason. If you cannot configure your router or firewall, you cannot send in the normal fashion and must use another form of connection.
Various scripts call this different things such as "firewall workaround" or "reverse DCC" from two of the main scripts that allow this. All it really does is uses DCC Chat instead of a true Fserv to serv things.
The command /dccserver sets a mIRC option which you can access and change without using that command. It is located in the options (Alt-O), DCC > Server.
+sc means to activate the listening for sends and chats.
-f means to deactivate listening for fserv.
on ____ sets the port to listen on.
These commands have NO effect on your connections to any fserv other than one using this method and does not affect your security in any way different than using normal DCC. Usually, you already have the things activated and set to port 59 by default anyhow. Note also that you don't have to use -f on these... only +sc is important.
Now, for why you see different ports... people use whatever ports they have open on their router/firewall or whatever ports they have decent speeds on. If you use normal DCC, there is a port range where you'll see it saying you are getting a file from port _____ one time and a different port the next. With the workaround, you can only use a single port. That's why this has a port listed.
If you want to access one of these servers, you either cannot have a router or firewall, or you need to forward the port that is listed to your computer through the router/firewall. Note that this would also allow you to serv if you did this.
Is it safe opening a port? Well, that's up to you to decide. I can say, however, that you have a better chance of being hit by lightning or winning the full lottery than being hit by a hacker unless you make one mad somehow. And although you have to worry about viruses possibly getting in through a port without direct control by a hacker, if you run a decent anti-virus program and keep it updated, you have nothing to fear from that. It's all a matter of how concerned you want to be about being attacked and how much you want a file.
