Learn about IP and how it can point right at you and your location

Introducing the IP (Internet Protocol)

What´s the IP? The topic of IP is a complex one, and here we can only touch on the basics. The reader is actively encoureged to research on their own. For the sake of simplicity, we will say that the IP number is very much like a phone number, identifying EVERY computer ON the Internet with a specific number, UNIQUE TO that particular computer. The IP address is to the computer as your fingerprint is to you: it is unique, such that there cannot be two computers with the same IP address.

IP Internet addresses are 32-bit (4 bytes) long logical numbers, normally written as 4 bytes or octets (in decimal form) using the numbers 0 to 255 and separated by periods, e.g. Althought 8 bits have 256 possible combinations, the 0 and 356 are reserved. Both networks, hosts and clients can only use 0 through 254.

Originally, addresses were broken into classes-A, B, C and the IP addresses were assigned by InterNIC (internet Network information Center) the agency responcible for Internet addressing and managment, and is currently owned by Network Solutions. The class system is no longer in use, but it still can provide an easy way to describe the networks. The first octet or byte is the class.

CLASS SIZE OF NETWORK ADDRESS RANGE Possible Networks Possible # of Computers
per network
Class A Very large the first octet is the class, the 3 others are for the computers (hosts) 1.xxx.xxx.xxx through 126.xxx.xxx.xxx it allows for 16,387,064 computers to be attached to one network
(254 X 254 X 254)
Class B Large 128.xxx.xxx.xxx through 191.254.xxx.xxx limited to 64,516 computers
Class C Small from 192.xxx.xxx.xxx through 223.254.254.xxx 621,999,996 limited to 254 clients(computers)

Anything sent over the internet needs a 1. specific origin and 2. a specific destination. For this reason, every computer must have it's own IP address. The IP information is placed in the header of the data being transferred to ensure correct forward and return data transmission.

So Watch your Trail!

Since your IP is attached every time you request a page, that IP address is sent to the page that you are browsing (along with a LOT of other personal information). What OTHER personal information?..Just about everything about your computer- the OS, the name of your computer on the Net(from Net BIOS), (to check the name of your PC on the Net, do the following: find your Network Neighborhood Icon, select Properties, then the Identification tab. Right there is your computer's name, which could have been set by some other piece of software. Change it to something else, click on ok. I believe you'll have to reboot your computer before the change takes affect) your email adrress, the Time, the Date, Browser Type, Referer from(where you came from or the last web page before the current one even silly things like your screewn resolution, ets, ets For more info on what information your browser sends out read the The Secret Life of your Web Browser Revealed! FAQ . All this info (IP address + everything else) can be recorded by the host site through Java/Javascript, a counter, . The newest idea is to include a counter one pixel wide hidden inside an image to grab your IP number. Some Bulletin Boards even post your IP along with your post, making it available for anyone to see. This is why we recommend using an anonymizer OR proxy whenever surfing the web, and especially when browsing unknown sites or posting to boards. See the next section (- Anonymous Surfing) for more information on using anonymizers.

Hotmail and other "anonymous" mailers send your IP in the header of your message. We suggest that you use an anonymous Remailer to send e-mail, and include your hotmail address (or other mail address not associated with your own ISP) in the message if you want a reply. One good Remailer can be found at: http://www.gilc.org/speech/anonymous/remailer.html.

For more Remailers, ideas, read Proxies and where to find them, Remember that its best too err on the side of caution. The fewer that see your IP, the better.

Static vs. Dynamic IP's

The IP may be Static or Dynamic. A static connection means that your computer has one specific IP address assigned to it, and keeps that number irregardless of whether you are logged on or off the local network or the internet. A dynamic IP means that when you log onto the network, your ISP (Internet Service Provider) assigns you the next available IP address from its bank of available addresses. That address remains assigned to your computer until you log off. The next time you log on to your ISP, you will most likely have a different IP number. The ISP computer writes in its internal log file "at hour xxxx date xxx the user xxx is using the xxx.xxx.xxx.xxx account".
Dynamic IP's are used by nearly every ISP. The reasons for this are simple. First, with more and more people accessing the internet, many with multiple accounts, there would be a shortage of available IP addresses if everyone had there own. Also, assigning each computer a static IP would tend to make a mess for the backbone routing systems, causing fragmentation, and a great loss of efficiency of routing, resulting in longer transfer times.

DNS (Domain Name System)

You know how you can just type www.microsoft.com for example and you will be connected to them. Well this is accomplished with the Domain Name System - DNS where an name is mapped to a particular IP address, since it is easier for us humans to rememeber a name than a string of numbers. This adress name sets itself together from all other names. As an example IP adress this is the combination for the ftp.urz.uni-heidelberg.de (university - heidelberg - germany) On the left site ever stands the PC name in this example it is "ftp" this name could be any other name too.The administrator sets it up. The next is "urz" this keeps all the PC's in the calculating mashine center together. Followed by the domain "uni-heidelberg" that keeps all the PC's from the whole university together. And at last "de" it's the "top or level" domain for all PC's in Germany.

What about the ISP logs?

Okay, so now your ISP has a log of who is logged in under which IP number at any particular time. They also maintain a log of data transfers, logging each transfer of information, the originating IP, and the destination IP. So it might seem a routing process to do a search of the logs and find any illegal activity, and associate it with the exact computers involved.
So why do the ISP's maintain logs of all internet activity? Mostly for the purpose of debugging. If the ISP servers develop a problem or they crash, technicians may scan the logs to determine if a particular transfer was involved with the problem.
Now consider a normal day surfing the web. In a normal day I can download/upload 2000 or 3000 files (the gifs of the pages, the wallpapers, etc. etc.). Now if the ISP has 10000 or more clients (normally an ISP needs at least 10000 users to survive)that results in: 10000 x 3000 = 30,000,000 operations in a day. Every line has 128 lines (or bytes) = 3.840.000.000 bytes... wow! The logs takes 3 Gigas from the disk !!! :) and I dont know an ISP who will waste this much memory for more 3 days. Consider also the amount of time and money it takes to go through those logs looking for something that the ISP doesn't want to find in the first place.

The Dangers...

However, if a federal agency has a search warrant with probable cause, they have the authority to demand a search of the logs. If the logs for that time period are available, they can trace that data transfer to you. If almost anyone else gets your IP address and tries to identify you, they have practically no chance of doing so.

Your biggest danger is if you are using a computer at work, at school, or in a public library. They keep their own logs, which are usually much smaller than a regular ISP. They also have more incentive to search their logs, to keep their image clean, and keep an eye on the activities of their employees/students. We recommend that you do not use such computers for any questionable activity.