Packet-switching across a network

There is so much information around us. As Floridi puts it, Information is notorius for coming in many forms and having many meanings. Over the past decades , it has been common to adopt a General Definiton of Information (GDI), in terms of data and meaning. That means that we can manipulate it, encode it, decode it as long as the data must comply with the meanings (semantics) of a chosen system, code or language. There has been a transition from analogue data to digital data. The most obvious difference is that analog data can only record information (think of vinyl records) and digital data can encode information, rather than just recording it.

But how is the information measured?

Claude Shannon, in his publication “A mathematical theory of communication”, used the word bit, to measure information, and as he said, a bit is the smallest measuring unit of information. A bit has a single binary value, either 0 or 1.

When I think of information, I almost never associate it with data, but rather with meaning. In a way, information to me serves the function of communicating a message. But, when we look at how is the message sent and delivered, is when we can see the data in it.

Shannon’s first diagram, a version of which he used for encryption and
decryption techniques in World War II, outlines a simple, one-way, linear signal path
without the surrounding symbolic and social motivation for the signs and symbols
encoded, transmitted, and decoded.

Now let’s take a look and see how information is sent over the web, and how computers exchange data.In 1961, Leonard Kleinrock introduced the packet-switching concept in his MIT doctoral thesis about queuing theory: “Information Flow in Large Communication Nets”. His Host computer became the first node of the Internet in September 1969, and it was the first message to pass over the internet.

So how does packet-switching works?

An animation demonstrating data packet switching across a network.

First, the TCP protocol breaks data into packets or blocks. Then, the packets travel from router to router over the Internet using different paths, according to the IP protocol. Lastly, the TCP protocol reassembles the packets into the original whole, and that’s how the message is delivered.

When you send e message from your computer to a friend, using the Internet as the mean of this communication, that message is divided into packets/blocks as we saw earlier, it finds different paths from the modem, to the router, finds the Domain Name Server and then the appropriate Web Server using the Internet Protocols, and at this point the message is than reassembled into the packets from the original whole, and that’s how your friend receives that message. There is a trade of complexity and performance that happens while using these design principles, but the end goal of this architecture is to effectively have the flow of information, the transmission of the data packets from one end of the server to the other

As Dr. Irvine explains, information theory contributes to the designs for the physical architectures and kinds of digital information encoding and decoding that we now
use in well-recognized, standardized formats and platforms. So, information theory and semiotics gives the more complete picture of meaning-making in our digital
electronic environment.

Reference:

Floridi, Luciano. Information: A Very Short Introduction

Gleick, James Excerpts from The Information: A History, a Theory, a Flood. New York, NY: Pantheon, 2011

Irvine, Martin. Introduction to the Technical Theory of Information

Claude E. Shannon, E. Claude. A Mathematical Theory of Communication.The Bell System Technical Journal 27 (October 1948): 379–423, 623–656.