The Magic of the Internet Protocol
As you read this article today, take a moment to think about the miracle of its arrival on your PC, tablet or smartphone. Every bit and byte from my desk has arrived perfectly on yours. It might have travelled via optical fibre, coaxial cable, twisted pair ADSL, under-ocean cable, satellite or terrestrial microwave transmission. But thanks to the Internet Protocol (or IP), data transmission is standardised and can drive business, finance, social media, email, Zoom and the Internet … transparently. Isn’t that exceptional? Yes.
We forget how exceptional this level of standardization is when it could so easily have been otherwise. Our lives as consumers are plagued by devices and standards which differ across countries. For example:
1. Motorists in the USA and continental Europe drive on the right; the UK, Australia, southern Africa and the Indian sub-continent drive on the left;
2. Mains electricity plugs vary so much (at least 15 types of round-pin, square-pin, two-pin, three-pin) that airport boutiques form a cottage industry selling adapters to allow you to use your equipment when you travel;
3. Apple makes an immoral business of changing the type of charger plug to connect to your device; the pre-2014 30-pin connector; the MagSafe power cable; the Lightning cable on new 2018 iPad Pro; non-standard USB ports. Can a brief moment of sales of Apple’s own cables, before the aftermarket chimes in, really outweigh the confusion they sow, the jumble of wires at our charging stations and the antipathy of their customers?
4. Americans abbreviate their dates to MM/DD/YYYY; 9/11 for them means the 11th of September. In many other parts of the world, dates are written DD/MM/YYYY: 9/11 means the 9th of November.
For all the unity that globalisation has brought about, it is a great irony that we still cannot standardise on such basic principles.
In stark contrast, the Internet seems to work by magic. It appears simple. But underneath is a miracle unparalleled in electronics and industry. Arthur C Clark’s comment about advanced technology being indistinguishable from magic is at the heart of the Internet. The magic ingredient is called the Internet Protocol.
How did it come about?
Inter-networking is the problem the internet was invented to solve. It presented enormous challenges, even defining hand-shakes, ASCII text codes, national and language differences, operating systems and addresses. Getting computers to talk to one another (networking) had been hard enough. But getting networks to talk to one another (inter-networking) posed a whole new set of difficulties, because up to the late 1970s the networks spoke alien and incompatible dialects. Trying to move data from one to another was like writing a letter in Mandarin to someone who only knows Hungarian and hoping to be understood. It didn’t work.
In response, the architects of the internet developed a common language that enabled data to travel across any network. In 1974, two ARPA researchers named Robert Kahn and Vint Cerf published a design for “a simple but very flexible protocol”: a universal set of rules for how computers should communicate. These rules had to strike a very delicate balance. On the one hand, they needed to be strict enough to ensure the reliable transmission of data. On the other, they needed to be loose enough to accommodate all of the different ways that data might be transmitted. Cerf said “You couldn’t write the protocol for one point in time, because it would soon become obsolete. The military would keep innovating. They would keep building new networks and new technologies. The protocol had to keep pace: it had to work across an arbitrarily large number of distinct and potentially non-interoperable packet-switched networks –including ones that hadn’t been invented yet.”
Eventually, these rules became the Lingua Franca of the internet. But first, they needed to be implemented and tweaked and tested –over and over and over again.
There was nothing inevitable about the internet getting built. It seemed like a ludicrous idea to many, even among those who were building it. The scale, the ambition –the internet was a skyscraper and nobody had ever seen anything more than a few stories tall. Even with a mass of cold war military cash behind it, the internet looked like a long shot. Then, in the summer of 1976, it started working.
What is this common language? The Internet Protocol (IP) is the method or protocol by which data is sent from one computer to another on the Internet. IP has two key standardized elements that are involved in every transmission:
- a common method for breaking each transmission down into small chunks of data (packets up to 576 bytes each that have a 24 to 32-byte header – information on the origin and destination and the size of the packet, and;
- a unified global addressing system, a unique address (four eight-bit numbers separated by periods) for every computer and device so that data that can be delivered to the destination.
A good example of the IP in action is email. The Simple Mail Transfer Protocol (SMTP) is the communication protocol for email transmission, first defined in 1982. Type your message, hit send and it gets delivered to the unique email address of the recipient. Another example of IP is the worldwide web; click on an internet link –a Uniform Resource Locator (URL) or web address –and your screen shows images, data and media exactly as the originator uploaded it. Nowadays we take the magic of the internet for granted.
By itself, IP could not ensure that the packets arrived in the correct order, or even that they arrived at all. That’s the job of another protocol: TCP (Transmission Control Protocol) which sits “on top” of IP and ensures that all the packets sent from one machine to another are received and assembled in the correct order. Should any of the packets get dropped during transmission, the destination machine uses TCP to request that the sending machine resend the lost packets, and to acknowledge them when they arrive. TCP’s job is to make sure that transmissions get received in full and to notify the sender that everything arrived OK.
Every computer connected to the Internet is capable of doing a few, very simple tasks very quickly. By linking millions of comparatively simple systems together, complex functionality is achieved. The Internet is an ingenious communications network in large part because it is so simple, and this enables it to empower anyone, from any culture, with any application, anywhere in the world.
So if you are reading this from a remote island far across the Pacific Ocean, using a solar-powered Kacific antenna and modem, thank your lucky stars for the Internet Protocol, a rare example of standardisation in a fractured world.
Marcus Bicknell is Senior Marketing Advisor to Kacific Broadband Satellites; he was commercial director of the world’s first privately-funded satellite operator SES Astra from April 1986 and was a Non-Executive Director 2005-2018. The views expressed in the article are his own.
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