Introduction to networks
When I was designing this article (yes I design this stuff) I was tempted to start defining terms and getting definitions from dictionary but after thinking twice I though: After such many time and experience It will be possible to write this article using the data you all ready know with your own words?. After this I analyze for 2 minutes and though: well this is my web site so why not? So this is the deal:
Networks are simple and just a medium to connect 2 or more devices between them. For example, the next 3 images show different types of devices and mediums.
On all this scenarios the main purpose is the communication process, to transfer data from one point to another. The most used and common network is the Internet. The next image shows how different countries interconnect with submarine cables:
Taken on: 7/7/2014
The networks integration is a tendency on these days. For example the cellular network connects to the Internet network, this is the reason why you can send and receive e-mails transparently. All technological progress had made us forget the functional fundamentals of things. How is possible for all these communications to take place? Well it is simple (not, is not), everything is boils down to computer language (0 and 1) and the different methods and/or medium used to send those 0 and 1. In order to understand how this networks works lets see a most common example, sending a letter (for those that had send a letter before). When dinosaurs lived and you want to communicate with another human being something called letter was written. This was amazing because the hand was used for this purpose and things called pencil and pens where the tools used (this is the reason why we had been taught to write at the first place). The postman pickup the letter and deliver it to central facilities using the mail-buss. From there the letter is delivered to the correct person. The next image shows a simplified version of the process:
Step 1; you write the letter. Step 2; Put the letter on the envelope. Step 3: The postman pickup the letter. Step 4: The mail-buss deliver the letter to the central mail facilities (step 5). After this 5 steps the process is reversed in order to deliver to destination. First, from the central facilities a mail-buss pickup the letter, a postman deliver the letter, the person open the envelope and read the letter. Simple no?, well the Internet works just like this process. Lets check the process using electronic mail (better know as e-mail) send scenario:
First you write an e-mail (step 1). Then your device (computer, telephone, tablet, intelligent watch) put the content (in binary language 0,1) in packets (step 2). This packet is delivered to the switch (step 3) and the switch deliver it to the Router (step 4). At last the router deliver the packet to the Internet (step 5). Each step is equivalent to the example of sending the letter. In order to visualize better both process I set side by side both images.
The first two steps of the examples are not part of the network. Steps 3 to 5 are the ones involved with the network. The network is the responsible of carrying data from one point to another. As the letter example when the packet is in the Internet it will be sent to a router, the router will sent the packet to a switch, the switch to the device where the device will open the packet and show the content in a way the user can read it as an e-mail.
