Question about IP addresses.

[David]

For another explanation of how IP addressing works, see this quote from a while back:

quote:Originally posted by DJHyperbyte

Firstly, let me clear something up. An IP address is not something special or secret. It's not a number that contains all your personal info and it will not make you coffee.

An IP address is simply an address that network devices (such as computers and routers) can use to reach other network devices in a network. You could see it as a street address. The network is the street and each network device is a house. So, let's say my IP address is '192.168.0.5', then I live in the street '192.168.0' and my house number is '5'.

Now every street has at least one postman. The postman knows the locations of other streets and other houses. Let's take a simple example: you connect to MSN Messenger. You click on the 'Login' button and then your computer immediatly asks the postman "Hey, send this letter to MSN! I want to login!". The postman sends the letter with your username and password to MSN Messenger and then MSN Messenger sends a letter back to either deny or confirm your login.

--- At this point you have already given your IP address to at least two other network devices. The postman in your street and the computers at MSN.

Now you are going to send a file via MSN Messenger to a friend. Your friend clicks 'Accept' and with that, his computer sends you a letter containing: "Yes, I want to accept the transfer. This is my address...".

--- Now at least three computers know your IP address. Your postman, the computers at MSN and your friend's computer.

This is, greatly simplified, how the internet works. Now your original questions:

• If I am not hooked up to the internet, does my computer have an IP address?
  If you buy a house in a street, will it have a house number? Of course! So as long as your computer is participating in a network it will have an IP address.
  
• Is an IP address determined by the manufacterer?
  No, this depends on the network you participate in. Often a network gives you an IP address automatically, sometimes you have to enter one manually.
  
• How do I find my IP address?
  This depends on what IP address you are looking for. If your computer is behind a router then you will have both an internal (LAN) and an external (internet) IP address. With the 'ipconfig' program (Start -> Run -> 'cmd' -> 'ipconfig') you can find your internal IP address. Your external address can be found by visiting this webpage. If you don't have a router, but are connected directly to the internet, then your internal IP address and external IP address will be the same.
  
• If someone hacked my computer, can they find my IP address?
  If someone broke into your house, then must know where you lived in the first place. So if someone on the internet has hacked you, then they knew your IP address already.
  
• Can someone gain administrative rights when they know my IP address?
  Simply put: no. But this really depends on your computer. It might be possible that there is a malicious program (such as a trojan) that opens a backdoor in your computer so hackers can walk right in. Generally, when your computer is behind a router or when you have installed a decent firewall, you don't need to worry about this at all.

Hope this cleared things up.

[This quotation has been revised from the original submission due to BBCode-version issues and broken hyper links]

Now for the previous question: Can someone tell I'm online with my IP address?

The answer is maybe. They cannot tell whether you are on AIM or not, but they may be able to tell if your computer is running or not. Depending on how your equipment is configured, your computer may send a response when asked for one. If this is the case--it's not a big deal, since most people leave their computers on all the time.

When you connect to AIM, you connect to a central login server, everyone connects to this same server (or cluster for your technical people--but thats not relevant). When you make a direct connection the AIM server uses some clever networking technologies to punch a hole in both of your firewalls and allow you to connect to each other directly and send data. During this process, you have a data stream between your and your buddy's computer. So yes, since you are sending data directly to them, they can get your address. But remember this is only while directly connected. If you are just chatting normally, all data is sent through the AOL server, and you are no more than a screen name to the person on the other end.

[Slickrick77]

Thats freakin' awesome!

[Slickrick77]

David, you said maybe they can tell if youre online, well, i hope your not misunderstanding me, what im trying to say is, if you wanna watch someone online, from a screen name they arent aware u have, they there is no way for them to know ur watching them or anyone else on that list of your b/c its via a name they dont associate with you, they can only tell ur online if they see the usual SN on that u use to chat wit them correct?

or are u also saying, no matter how many "covert/ secret" names u have, as long as they know the name u usually use with them, they can track your online status no matter how mnay new and diff. sn's you were to make?

Thanks D.

[patndoris]

I think what David's trying to say is they may be able to tell if your computer is physically ON from and IP address, as opposed to being shut down. They cannot tell what programs you're using, what screen names you may be logged into or anything else, simply that your computer is on and connected to the internet.

I don't personally use AIM, but with most IM programs, in order to "watch" a particular person, you'd have to be on their buddy list. If you don't accept unknown add requests you shouldn't have to worry about being watched. As a good safety practice - not only should you not accept people you don't know, but NEVER accept a direct file transfer from a stranger - photo, document, etc. or you could end up with a virus you didn't expect. Unless you're 100% sure of the source be very careful.

-Doris-

[RU Still Down?]

these days AIM servers can proxy "Direct Connections" (i know Pidgin supports AIM proxied Direct IMs). This is because most people do not know how to forward ports correctly. Also, as far as i know, AIM doesn't use UPnP to automatically forward ports on your router. So, you don't really have to be worried of someone finding out your IP through a direct connect unless you are not behind a router (i.e. are directly connected to your modem).

[Slickrick77]

Hey just for shoots and giggles, lemme put this wild one out there, you think are capabilities out there that allow people with AIM buddy lists to not only see when their buddies sign on, but also, simultaneously, the ip that goes with them also, also like an" ip buddylist"? just a thought..

Secondly...im aware that as of now, without a link in a aim profile, its impossible to see who views it, allegedly b/c aol has not created anything that has embedded tracking yet, m y question is, is there any update to this, are there embedded ways yet to track views without a link?

[Slickrick77]

anyone?

[EEDOK]

1st question, it'll only work if they don't have a firewall that blocks incoming traffic requests, 2nd I wouldn't imagine them doing so.

[dvelez1985]

You can do a whois on the IP and you can find out what physical address that IP is registered to. I've done it on my own and the schools computers. You can try it yourself if you know your IP google whois or download the one from sysinternals.com and do a whois on your own IP to see what you get. As far as hacking unless they have some kind of trojan they really can't hack into your computer the most they can do is stalk you.

I was wrong you can find out the info of the service provider. When I tried whois out I did it at school and their ISP gives all the info about the school so I thought it was the same for homes.

[ahoier]

Theoretically, you could "ping" an IP address to see if they (a buddy, I presume...) is "online". But even so, depending on your "buddies" service, they may have a "dynamic" address, which means everytime their modem/router shuts off, they are assigned a new address. This could/would only really work if your buddy has a "static" IP address.

Even so, some routers (and most software firewalls) are equipped to block ICMP (Ping), so even if they are "online" they will not respond to your ping, making you look like they are offline.