In our various discussions of network technology and equipment, we’ve referred to the concept of an IP address on multiple occasions. The “IP” in “IP address” stands for “Internet Protocol.” It’s the communications standard that powers the entire Internet. All of the various servers, routers, and computers, from supercomputers to smartphones, communicate using what’s known as the Internet Protocol. The combined software suite that governs both basic packet routing and more advanced functions, such as the World Wide Web, is called TCP/IP.
A digital IP address functions very similarly to a physical address for your home or apartment. When you attach your computer, tablet, or smartphone to a router, you are assigned a private IP address. These virtually always begin with the digits 192.168.XXX.XXX. A common IP address, for example, is 192.168.1.100. The second system connected to the router would then be assigned 192.168.1.101. These local, private IP addresses tell your router how to find each individual system on its network, in the same way that your street address tells your postal worker how to find your individual house.
This raises the question: How does traffic get from Google.com to your router in the first place?
A typical home Internet connection consists of a cable or ADSL modem connected to a router. All of the Internet-capable devices in the home connect through the router, which assigns them their respective private IP addresses. The cable modem has a public IP address, derived from your geographical location and your local Internet provider. Comcast, for example, has its own bank of IP addresses, as does Time Warner Cable, AT&T, Verizon, and a variety of other academic, governmental, and corporate institutions across the US.
The digits that compose your public IP address tell the servers your router communicates with precisely how to route the information back to you, in the same way that the combination of a zip code and street address tells the post office how to transfer mail. No, the server at Google doesn’t necessarily know where your house is – but it doesn’t need to. It can return the information you requested to your cable modem’s network address. The network then passes this information to the router, and the router – your local postman – knows the exact location of your house.
One of the strengths of the IP address system is that both the public and private pool of addresses can shift on a regular basis without anyone on the Internet losing track of anyone else. While routers can assign static IPs to anyone on the local network (to ensure, for example, that advanced router functions work properly), the IP address you are assigned by your ISP likely changes on a regular basis, unless you pay extra for a specific IP address. This system is designed to ensure that no pool of computers can sit on certain addresses for an unduly long period of time, but the change from address to address is smooth enough that you’ll rarely notice it.
The neat thing about IP addresses is that using them takes you a step closer to how your PC actually processes Internet addresses and locations. For fun, hit the Windows key, type “CMD” (no quotes), press “Enter,” and then type “Ping Google.com.”
The window will then display the following: “Pinging Google.com [XXX.XX.XXX.XXX] with 32 bytes of data.” Open a browser window, and type the same digits into the bar where you’d normally type “Google.com.” Press “Enter,” and you’ll find yourself at the popular search engine without ever having typed the company name.
IP addresses are the backbone of how data communication flows across the Internet, from your local router to far-flung servers in faraway countries. Not bad for a string of digits and dots.
The post What is your IP address? appeared first on Speedtest Blog.