What is an IP Address?

We live in a world of networks. Networks are literally everywhere, from power grids, roads, cell towers, financial and legal networks to social networks, and, of course, the Internet. Networks lay over each other and touch all over the place. We navigate them daily, often without even noticing they are there, but have you ever thought about how a network might see you? To a financial network you might appear as an ID number with an amount attached to it, to a cell phone network as data, meta data and location data.

We recently learned that our phones are tracked and tapped, every step of the way. However, our phones can only work when they know where they are and constantly inform the phone company about it. That’s not surveillance, that’s just how the technology works.

The Internet must also know who you are and where you are located. It does that through a number your Internet Service Provider (ISP) assigns to you, your Internet Protocol address, better known simply as your IP address.

What is an IP address?

Computers need to speak a common language, that language is called Internet Protocol. They communicate by sending packets of information that include the IP address of the destination computer. Simply put an IP address is a big number that identifies a computer on the Internet. Currently the majority of Internet traffic is routed using Internet Protocol Version 4, or IPv4. This addressing scheme was adopted by the IETF in 1981, and consists of 32-bit numbers organized in 4 octets, 74.125.227.99 (google.com) for example.

Vint Cerf, now an Internet Evangelist at Google, could not have foreseen the number of IP addresses needed when he picked the 32 bit address space. Even though roughly 4.3 billion IPv4 addresses exist, only about 14% of them are in active use according to an article from 2011. This number is probably higher today, but nowhere near 100%! Originally they were handed out in large chunks  for free to anyone who showed interest (IBM, Apple, AT&T, DoD, etc.), leaving millions of IP addresses unused. While some organizations are voluntarily returning their unused address space to ARIN, others aren’t.

The IETF formalized the successor protocol IPv6 in 1999. IPv6 addresses are 128-bit numbers displayed in 8 groups of 16. This allows for 340 undecillion (3.4×1038) IP addresses, about 100 addresses for every atom on the surface of the earth. Based on Google’s traffic analysis, at this time about 96% of Internet traffic is routed using IPv4, and the other 4% is routed via IPv6. Because the headers of IPv4 packets differ significantly from IPv6 headers, the two protocols are not interoperable and it is expected they will be used side-by-side for the foreseeable future.

What information can be gleaned from an IP address?

Every device connected to a network must have an IP address to receive data. This is not much different than a postal address or phone number – without an address or phone number nothing can be routed to the intended recipient. Interestingly, the domain name system (DNS) is an extension of this system to make addresses easier for humans to remember (google.com translates into 74.125.227.99).

The important point here is that IP addresses (IPv4 and IPv6) are assigned, therefore there is a trail leading from the highest assigning authority (ARIN) to your ISP and from your ISP to you, or, more simply put, your IP address uniquely identifies your device on the Internet just like your fingerprint identifies you offline. Your IP address becomes your identity on the Internet.

IP addresses serve many useful functions, but they can be used against you. Therefore, it is smart to know how they are being used and how you can use IP addresses to your advantage.

Network Information

Internet Service Providers (ISP) usually own a range of IP addresses that they purchased and registered through ARIN. Time Warner Cable Internet LLC, for example, owns 24.92.0.0 through 24.92.143.255. Consequently, if you are a Time Warner Cable customer you will be assigned an IP address within that range.

Anyone with access to your IP address can easily look up the network you are connecting from by searching ARIN’s registry entries.

Location

Not surprisingly your IP address indicates your location. If you’ve ever gotten a message from Youtube that some content isn’t available for your location, then you know what I mean. While this isn’t 100% accurate, it is accurate enough to use IP addresses to restrict content to certain locations. Entertainment streaming sites like Hulu and Pandora use your IP address to determine if you are eligible to use their service. Let’s call that Macro-Location to distinguish it from the more precise Micro-Locations.

Your Macro-Location is determined by converting an IP address into an IP number and then looking up the IP number (the result of the calculation) in an IP-Country database.

Some websites show your location on a map, sometimes with astonishing accuracy (Micro-Location). However, this isn’t a function of your IP address itself, rather it is a function of cross-referencing data points from different sources using your IP address as the common denominator. The accuracy varies greatly depending on the number of data points available to the specific site.

How can you use IP Addresses to your advantage?

All devices connected to the Internet must have an IP address, otherwise the Internet would stop working the way it does. Every server, every router, and every switch must know where to forward the packet to, therefore every device has access to the origin and destination IP addresses. Again, this is not surveillance, it’s the way this technology works. Many devices on the route your information travels are potentially capable of logging and storing this information.

While you can change your real IP Address (by restarting your cable modem, for example), you will still have an IP address that can be traced back to you and which correctly identifies your Macro-Location.

To hide your real IP address all you need to do is to put a proxy-server between you and the rest of the Internet. Instead of your computer sending out requests with your IP address to the Internet, your computer sends your requests to the proxy server which replaces your IP address with its own then sends your requests to the internet and then channels responses back to you. This technique allows anyone to bypass region and content restrictions, and to hide their identity from prying eyes. How does one do that, you ask?

Proxy Server

A proxy server is a server or an application that acts as an intermediary for clients (such as your computer) to request resources from other servers (a web server for example).

Proxies can perform many functions such as security, caching, filtering of data and content, translation, logging and eavesdropping, bypassing filters and censorship, or accessing services anonymously. For the purposes of this article only anonymizing proxies, also called web proxies, are of interest.

By connecting to the Internet via a web proxy you can change your IP address to that of the proxy server, thereby bypassing region restrictions and hiding your real IP address.

VPN

A Virtual Private Network (VPN) is a private network within a public network; private, because you need login credentials to connect, and public, because you connect through the Internet. VPNs are a hot item since the days of Edward Snowden, and you have literally hundreds of options to choose from – free or paid, anonymous or not so anonymous – but more about that later. VPNs function essentially like a proxy server but offer better security because the connection between you and the server is encrypted, making it impossible to eavesdrop on your Internet activity.

While just about anyone can run a proxy server, VPN servers are usually owned by businesses, therefore eliminating – to some extend – the mystery of whom you are doing business with and trusting with your data. However, keep in mind that every rule has exceptions and only connect to proxy servers, including VPNs, run by people you trust!

Tor

The Onion Router, known as Tor, is a free service comprised of the Tor Network and the Tor Software. After connecting to the Tor network the Tor software randomly chooses a minimum of three relay points – think of them as proxies – to establish an untraceable route for each data transfer. Information packages are wrapped in layers of encryption – like an onion – for each relay point, or node, to peel off just one layer in such a way that no node knows the entire route, effectively hiding the origin of the request and the destination the response will be sent to.

Similar to a VPN your HTTP request is sent via an encrypted connection to a Tor entry node, then takes a random path through the Tor network to a Tor exit node from where your request is sent openly (not encrypted) via the Internet. However, in contrast to a VPN you don’t control the location of the exit node, therefore Tor is less useful to navigate geo-fencing, but is great at anonymizing Internet traffic, hence used by many who have a vital need for privacy.

Summary

Your IP address, your unique online ID, serves many useful functions, but also imposes limitations because it provides location information about you and can ultimately be traced back to you personally, fortunately (in most cases), not without a court order or similar legal premise.

Hiding your real IP address is easily done by establishing a connection to a server or service – known as a proxy – that acts as an intermediary between you and the Internet.

Proxy servers offer the most basic way to hide your IP address and your location. However, proxies also pose the highest risk as they are easy to setup and, unless you trust the person or organization who runs it, are not very secure.

VPNs offer higher levels of security, high speed, and the option to choose the location of your proxy (VPN server). They vary in price and features and the extent of their network from a presence in just a handful of countries with a limited pool of IP addresses to worldwide presence with thousands of IP addresses to hide behind.

Tor is probably the most secure service to choose if you want to hide your real IP. It’s free, run by volunteers, but it doesn’t let you choose your IP address location. Because of the elaborate encryption and routing process, Tor is slow compared to VPNs.

In the early days of the Internet changing IP addresses was limited to the few technically astute among us whereas today it is easily available to everyone. I hope you now have a clear understanding of what an IP address is and how you can change it to fit your purposes. For more information check out the references provided.

Reference Articles

Seeing Like a Network

Image Credit: Timo Newton-Syms

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