Tech Talk #27 – June 11, 2016

We get the word “internet” by combing the first parts of the words interconnected and networks. The internet connects millions of smaller networks, each owned independently, but connected with all the other networks.

 

Arguably, the internet has changed the world more than any other technology in history and has had the fastest adoption curve of any technology in history.

 

Here are the major components of the Internet and what they do:

 

Your computer – Opening your favorite browser and typing in “facebook.com” starts a specific chain of events that happen quickly. Here’s what happens: Your browser tries to figure out the IP address for “facebook.com” using Domain Name Service (DNS) queries (we can go over the mysteries of DNS in another column if you want.) Once your browser “knows” the IP address of the facebook.com server, it sends a GET request to that IP address.

 

Your router – Your router receives the IP address from your browser, looks around on the network in your home or business to see if it can get to the address locally, and if not, it sends the IP address request to your modem.

 

Your modem (the gateway) – Your modem sends the IP address request to a bigger network owned by your Internet Service Provider (AT&T, Brighthouse, etc.) over a combination of copper and fiber optic cables.

 

Your Internet Service Provider (ISP) – Your ISP sends your request to its Internet Point of Presence.

 

A Point of Presence (PoP) –An Internet PoP is an ISP’s access point to the internet. It’s an actual physical place with servers, switches, and routers. It might belong to your ISP or it might be a co-location space with a telecom carrier. ISPs typically have multiple PoPs for redundancy and load balancing. At the ISPs PoP, your request is sent to an Internet Exchange Point for access to the Internet.

 

An Internet Exchange Point (IXP) – An Internet Exchange Point is another actual physical place with even more servers, switches, and routers. Here, your ISP can access the networks of other ISPs. Now that your ISP can reach the IP address you requested using other the IPS’s networks, your request is sent to a datacenter using an Internet Backbone.

 

Internet Backbone – An Internet Backbone is a high-speed fiber optic wide area network connecting the lower-speed networks. A country typically has several backbones linking all of its ISPs. National backbones interconnect in a mesh with the backbones of other countries, usually via land or undersea cables or satellites, and exchange Internet traffic between countries, continents and across the oceans. So now your request can be sent to the correct datacenter.

 

Datacenters – A Datacenter is another actual physical place with hundreds or thousands of servers, switches, and routers where a company stores content on servers. Currently, corporations and telecom carriers currently own more than 500,000 data centers all over the world. Microsoft has more than 1,000,000 servers in their data centers. Facebook has more than 900,000 servers in their data centers. One of the servers in a data center receives your GET request, processes it, and sends you the result, following the reverse of the path your request took.

 

Sounds easy, doesn’t it?

 

Note: I’m not talking about the World Wide Web in this column. Tim Berners-Lee invented the World Wide Web in 1989. He combined hypertext with a transmission protocol and created the Hyper Text Transfer Protocol (HTTP) to transfer information between two terminals connected by an internet. The internet is the plumbing that delivers the WWW.

 

Parents these days…

Eat your veggies or I’ll change our WiFi password!

 

Do you have a computer or technology question? Greg Cunningham has been providing Tehachapi with on-site PC and network services since 2007. Email Greg at greg@tech-hachapi.com.                                                                                                                          

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