learning-tech-publicly

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Names & Numbers: How Data Finds its Destination on the Net

As explained before, the Internet is the global network of networks. And with billions of computers and devices connected to the Internet, how does data know where to go when it is sent?

When the foundations of the Internet were being laid in the early 1970's, Vint Cerf and Bob Kahn developed the first internetworking protocol. A protocol is a set of standards and rules that are agreed upon for all future technology to follow. The protocols that followed as the Internet grew, allowed for the massive global network we find today.

One of those protocols, the Internet Protocol (IP), determines how devices are located on networks as well as the structure of addresses for data sent, much similar to how postal services follow a set structure for home addresses (a protocol). IP addresses currently follow the IPv4 (version 4) or IPv6 (version 6) standards.

IPv4 is a set of 32 numbers (32 bits) separated into 4 parts with 8-bits (a byte) in each part and written in dot-decimal notation. Here's an example of an IPv4 address (111.24.221.18). The first two bytes represent the country or region of the address. The third byte represents the subnetwork and the final byte the device on that subnetwork. By using 32 bits, IPv4 was capable of over 4 billion internet addresses. However, this was not enough.

Enter IPv6, a 128-bit addressing protocol. IPv6 consist of a set of eight hexadecimal strings, each 16-bits long. This increases the total amount of possible internet addresses to over 340 undecillion (10^36). Plenty to go around.

You may be wondering, but if I type in a website domain into my browser bar, how to I get to that website without typing in the specific IP address? Now it is time to introduce DNS or the Domain Naming System.

You know how when you want to save someone's phone number into your own smartphone, you type in a name and save it to your contacts. Then when you want to call or text that person, you just click on their name and soon you are connected. DNS works the exact same way but is better in another way. DNS works like that contact list in your phone.

There are a bunch of DNS servers that hold the addresses and domain names of all the websites in existence. When you type in the name of a website in your browser, your request is sent to a DNS server who then returns that IP address to your system so that you may set up a connection with the website server. If the particular DNS server does not know the address, it asks the vast network of other DNS servers if they know the address. Once it gets the correct address, the DNS server you originally contacted, will save that address for your convenience. Nifty huh?

However, DNS does have a downside. Because it an open and public protocol, it is possible for criminal elements to disrupt or manipulate the routing of the DNS server. An unethical hacker could perform a DNS spoof, which could force traffic meant for a legitimate website to be rerouted to a malicious website or phishing site.

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How information travels across the Internet

All data sent across the Internet is in the form of binary data, or a bunch of zeros and ones that computers understand and can translate into information usable by us humans. Each "0" or "1" in the bunch is called a bit.

The current major mediums for this bit transfer are; electricity over Ethernet wires, light through fiber optic cables, or radio from routers, cell towers, or satellites.

The electric transfer of data utilizes copper wires to move the bits between locations. Wired Ethernet connections are cheap and easy to setup and maintain. However, a downside of using electrical wires to transmit data is the possibility of signal loss as the distance of the wire increases.

Light can also be used to transmit binary data. The obvious benefit of using light is that it travels faster than anything else we can send. This light can be sent through fiber optic cables at very high speeds. And since fiber optic cables suffer little to no signal loss, these types of connections are used to cover vast distances like oceans. The major downside to this type of connection is the expense of using and working with fiber optic cables.

The final medium of bit transfer is through the use of radio waves. Most Americans are very used to utilizing this technology when their phones or other devices are connected to the Internet through Wi-Fi or cellular connection. Equipment such as routers are used to turn digital information into radio waves or vice versa. While there is a great chance for signal loss, degradation, or blocking when using radio waves, the ability to access the internet away from wired components makes it an invaluable way to transmit information.

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What is the Internet?

Before I define the Internet, I have to define a computer network. A computer network is a set of computers that are able to communicate with each other through a standard set of protocols (I'm sure these protocols will be defined more deeply in future learning). A network can be small, like a typical home network, which may have desktops, laptops, smart devices, and mobile devices linked through Wi-Fi or ethernet. Networks can be large like those belonging to business, education organizations, or corporations. The Internet is the global network of all these smaller networks.

The Internet came to be starting in the early 1970's. The roots of the network began with the Department of Defense and their Advanced Research Projects Agency Network or ARPANET. The design of the network was based on the need that the network must withstand a nuclear attack without losing communications between all the networks.

The final design, and still in use today, is the distributed packet-switched network. Every system and network is connected to every other system and network giving exponential connection points for information to travel. Bang! Internet created.

No single entity controls the internet, yet everyone controls internet.

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About this Blog

Hello, my name is Patrick and I have been learning information technology (IT) at a university for the past 3 years. This is a career change for me as I am in my 40's and currently a care taker for an elderly parent. Currently, I am an internship away from completing my degree (hit me up if you have an opportunity!). I do have experience in many of the subjects I will post on this blog but I want to keep learning move forward and reinforcing that which I have already learned. I am open to any criticisms or tips as I move through this continual learning process.

I came across this idea of learning publicly through this blog post here. In that article, the author mentions that most people learn in private and do not create content as they learn. This is a detriment to the learner as well as others that may find value in the knowledge learned.

The author also mentions to write the content for yourself and pay no attention to engagement, likes, or shares. Only focus on what you are learning and make it for yourself. Of course there is many more content avenues listed in that article, but for right now, it's Tumblr for me.

Here's to future me and future you.