I was on the ICQ chatrooms recently. So some idiot managed to get me into a swearing match with him. And so we swore a couple of times.
So I got kicked out. OK. Fair enough. Simple. Straightforward. I come back on with a new username and hey presto! I’m back in the chat. But something happened. I couldn’t get back on (with either my old nick or my new nick). What the hell happened?
It seemed to bar me completely from the chatrooms - I couldn’t even get onto it with a completely different username.
My instincts then told me (well it was obvious if you had half-a-brain-cell) that they had barred me somehow by tracing my address.
The wonderful news for me was that I am on a public computer system (i.e. a pooled set of public computers in big rooms which you must log on and off with a specified username and password). I am gathering that this means that there is no fixed address that they can trace. I logged off… logged back on and Hey Presto! , I’m back… albeit with a different username.
My Q is, how the hell did they know which computer I was using?
Upon further enquiry in the chat-room, I found out that they can apparently trace your ISP address (enlighten me - I have no idea what this is). How true is this? Does that mean the moderators could kick anyone out whenever they wish?
And if this occurs how can I protect myself? Is it specific for private/public computers? If I was sitting at home using my (private) computer and I got barred from the chat rooms would this be forever? And finally, how the hell do I get back on line once I have been kicked off (whilst sitting at home that is)…?
Whenever your computer is connected to the internet, it uses an IP (internet protocol) address so that the computers it connects to (IRC, web, usenet servers, whatever) know where to send the information you request.
Looks like you violated the terms of that ICQ server and got banned for good.
There are ways to get around it, but we’re not allowed to talk about them on the SDMB, because the Lynn et all would like to be able to, uh, band people for good.
If you’re on dialup, it’s usually as simple as disconnecting, then reconnecting, because your ISP assigns you a new ISP every time you dial in. That’s as much as I’m going to tell you.
Any time your computer is receiving information from a remote server, your IP address is visible.
ICQ makes your IP address particularly visible. I can see any connected ICQ user’s IP address (in Trillian) by hovering my mouse over their name. Through the ICQ client itself, there are various security settings (show my IP address to all users, to users in my contact list, to no users), but any script kiddie can get around this by luring you into a file transfer – that is, a direct connection between their computer and yours.
Some firewalls block web pages from picking up IP addresses, but ICQ will not run without being exempt from a few of the rules that prevent this. AFAIK, the only way to truly hide your IP address is to connect through a proxy (and even then, your IP is stored on the proxy server).
But they can still ban your entire subnet, which will not only keep you out, but also a lot of your fellow users on your ISP. They will probably have no idea why they have been banned.
Your ISP gives you a new one when you use a dial-up (and actually, most broadband connections change every couple of days) because they (the ISP) has a limited number of IP’s (Internet Protocal Addresses) to give out to there customers. So, for example, say that your IP has available to them X number of IP addresses. But they have twice as many customers. All of there customers can not log on at the same time because they don’t have enough IP addresses. So, what they do is when you log on, you get IP addres 155.155.155.100 (just BS numbers, by the way). Then you log off. Your IP address is then “available” to anyone else that logs on to your ISP AFTER you’ve logged off. So the next time you log on, you could get IP 155.155.155.125.
Hope that helps and hope I explained it correctly.
ISP addresses are dynamic. ISPs use a system called DHCP, the D is for dynamic. When you connect, the ISP’s server says “Gee, I have a range of, say, two hundred IP addresses, 14 are still open, I’ll give you number X”.
Home networks often use fixed IPs (though I think its a bad idea as a Linux DHCP server is easy to set up), but ISP will allot you an IP in their range on connection.
Well, no. IP addresses are only static if you have a connection to the Internet that is more stable than a dialup. For example, DSL users commonly have static IP addresses.
Of course, this is a question of how IP addresses are assigned: They are bought in bulk by those who buy Internet access from an upstream provider (such as your ISP buying from a larger bandwidth seller), and then, in the case of a dialup ISP, are kept in a pool to be handed out on demand. When someone logs on using that ISP, they are assigned an IP address out of the block their ISP has purchased. When they log off, their IP address is returned to the pool for reassignment.
This works because of the way routing is handled: Nobody has to deal with getting a packet from one end of the network to the other. Everyone hands them off to the next guy down the line, who, in turn, is only interested in knowing enough to make the next handoff. By the time a packet reaches your ISP, their routers can determine which IP address goes with which phone line at the moment. Therefore, discontinuities in which IP address goes with which machine can be handled at the lowest possible level.
(Incidentally, if the system outlined above sounds like it could survive nuclear holocaust, don’t be surprised. It was developed by the Department of Defense in the 1960s.)
Unless they check manually, they can’t tell whether I am on a subnet or not - I could be on a lease line. Besides, they have no idea which subnet I am on if I am using an ISP. No way they are going to ban a class A subnet, or even a Class B.
Under a new username, you said. They fully intended to ban you under your old one, so they blocked both that IP address and the username; and by logging out and back in you changed your IP address, so by registering under a new username you were able to get back on.
They could set masks, as well, where your PC name (based on IP) would be matched against a certain filter.
For example, you could set a ban against the imaginary *.florida.rr.com which would ban RoadRunner users from Florida.
Not as harsh as banning rr.com in general, but still pretty unhappy for the 99% of FL RoadRunner users who aren’t being abusive.
A certain IRC channel I used to frequent did bans this way.
The question is whether they can or not, it is whether they will or not. There are 65536 IP addresses in a class B subnet, and sure as heck they won’t ban all of them just because some person cursed a couple of times on one of them. Class C is still 256 addresses.
And why can they ban (and how) a specific set of numbers on the subnet? e.g.
???
Surely if they can identify the culprit (as they seem to be able to by this explanation - they can locate him in a target range at least) it is better to ban the specific user from the website instead of multiple numbers?
I understand that your IP numbers can get banned and that if you are on a dial-up your numbers are “available” to anyone when you log out (great explanation guys by the way DTFan and Derleth) and hence your IP number changes continously, but I don’t get about banning entire subnets (and why its even feasable).
A subnet is a network within a network. It’s a concept used when routing network traffic, so it’s not really the term that should be used here. IP range is more like it. And why? In a world where you could easily get a new IP by hanging up and reconnecting, banning a specific IP would be a short-term solution. But chances are your new IP would be very close to your old one. Thus some places will just ban all IPs very similar to the one that caused the trouble – 10.0.0.* if 10.0.0.24 was the problem, and especially if it is clear that one troublemaker has been connecting from a lot of similar IP addresses.
How? It’s what computers do. They look at numbers and make decisions based on them. They decide not to let your connection be established.