Unveiling ICT secrets— part II

In case you missed the first part of this article, here is a recap. I discussed the phenomenon of network congestion and said that its causes could be user dependant or equipment dependant. I discussed broadly what a communication network is although network assets remained black boxes. In this article I will endeavour to open the boxes. Before that, however, I wish to share some of the feedback from readers. Most of it was of encouragement nature. One person’s feedback was very interesting because it revoked some old memories. The reader critiqued the title of the article. The reader recommended that I should have called it “ICT Mysteries”. Indeed, I cannot agree any more, safe for continuity’s sake. Yes, they are mysteries until they are unveiled and become common knowledge. This critique reminded me of an incidence about six years ago when Information Communication and Technology (ICT) itself was still a big mystery, at least in Rwanda. It was during one of those happy-hours (we used to have many) when one Engineer of good repute stood up in our midst and with his usual slouch, adjusted his pants, clapped his hands to get our attention and went to ask, “Who of you knows what wa-wa-wa means?” Of course nobody answered back so he carried the day. After a few bottles and teases we were privileged to uncover the mystery. That ‘wa-wa-wa’ stands for World Wide Web. What a mystery, my foot! Today virtually every kid on the block knows what ‘www’ stands for, thanks to One-Laptop-Per Child. Fast forward, to the black boxes. The basic assets in a modern-day computer based network may be categorized into three groups: the end systems, the communication links and the switching devices. These include things like clients, servers, routers, hubs, switches, bridges, fibre optic cables, radio spectrum among other devices. You have probably heard this language before from the numerous ICT wizards around us. My fellow ICT mortals, please read on. End systems are nothing but computers used for different functions. These computers that you and I use to manipulate our communications are known as clients and those that the network uses to enable us manipulate our communications are known as servers. The clients and servers carry different application programs that enable network users to transmit and receive information. The e-mail, Web browsing, File transfer and chat are some of the application programs we use. The intercommunication between end users is done through the communication link. This is the physical media used for the interconnection. The media could be a radio link, coaxial cable, fibre optic cable or some other cable. Apart from their make the different media have a distinctive characteristic known as the transmission rate or bandwidth. You probably hear of Mbits/sec. That is no mystery! It is a measure of the transmission rate. It is an indication of how fast data will move through a particular medium if all other things are held at a constant. The different gadgets used to facilitate the network interconnections or even link with other networks are the switching devices. I will not go deep into these. After all we hardly notice their functions, as important as they are. Each of these assets plays a role in the management of data transmission from one end to the other. They regulate the data flow. Back to the highway analogy, the different assets could be compared to the road network assets like the round-about, the junctions and bridges, the Zebra-crossings, traffic signs, traffic lights and other assets used to regulate road traffic. Absence of such assets or their misuse could lead to traffic congestion. By now you probably feel like another ICT wizard (some are no better). On the other hand, if I have confused you more take heart. The next article will be much plainer. We shall discuss Network congestion management. The writer is the Managing Director of Cornerstone Africa Ltd www.cornerstone-africa.com info@cornerstone-africa.com

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Unveiling ICT secrets— part II