Basic Introduction to Computer Networks (Networking) For Beginners

Hearing the word computer networks or computer networking, perhaps in the minds of some people is a complicated thing. This is probably because there are explanations in the literature using high-level technical language that is difficult to understand by the layman. For that, I'll try to explain about the basics of computer networks by using imagery that is more easily understood even by lay people though ..

Local Area Network (LAN)

Also called a local computer network, because commonly used in the scope that is not too broad, such as in offices, schools, hospitals, etc.. LANs can also be called a private network (private network). LAN can be likened to such a housing complex, where there are several housing units in the complex. Each house must have a home number, right? Well, this term is a house number IP Address (Internet Protocol Address) or IP address, or commonly abbreviated as IP. IP containing an array of binary digits (1 and 0) along the 32-bit (IP address version 4) which is divided into 4 sections (WXYZ). So each section consists of 1 octet or 8 bits or 1 byte.

Giving IP address is divided into several classes: A, B, C, D, E. For the local network using a class C, where the first octet is worth 192-223. The first three octets (WXY) is used as a network identifier (network marker). While the last octet (Z) was used as host identifier (host markers or computer).

How to read binary numbers (binary):

eg 0101 binary digits (4 bits), if translated into a decimal number, the result:

(2 ^ 3) + (2 ^ 2) + (2 ^ 1) + (2 ^ 0)

= 0 x (2 ^ 3) + 1 x (2 ^ 2) + 0 x (2 ^ 1) + 1 x (2 ^ 0)

= 0 + 4 + 0 + 1

= 5

so, 0101 (binary) = 5

note: the sign "^" == rank

Then, why in one LAN maximum number of hosts is 255?

Answer: The host identifier to the IP class C size of 1 byte (8 bits) == 11111111 (binary) if it is translated:

(2 ^ 7) + (2 ^ 6) + (2 ^ 5) + (2 ^ 4) + (2 ^ 3) + (2 ^ 2) + (2 ^ 1) + (2 ^ 0)

= 128 + 64 + 32 + 16 + 8 + 4 + 2 + 1

= 255

Housing units in the above illustration is called the host. And each host has a name or a hostname (can be described as a house, for example the house of Mr Anwar, Pak Dedy, etc..). To access in and out of the housing is usually through a portal or gateway. In terms of networking, the gate is called the Gateway.

Giving an IP address can be either static or dynamic. Each has advantages and disadvantages. With a static IP, we are more easily identify or document the list of computers on the network. Dynamic IP requires a DHCP server function to assign IP addresses to hosts that request, so that in the host or the client is not required because the network configuration settings will be done by the DHCP server automatically.

Wide Area Network (WAN)

In a city of course there are some residential complexes. Inter-housing complex could be related to each other. Illustrations are used to describe the WAN, the computer network within a larger area than a LAN. WAN is a collection of several LANs. To be able to relate to each other, it needs a device called router. The router is what will set the policy (regulation) necessary for a LAN can be connected to another LAN. The device is the physical router can be a hardware or software that is installed on a PC (or called PC Router). WAN area is practically unlimited, other than between regions within a city, can also inter-city, inter-island, even between countries.

Hopefully with a little explanation of the above can add your insights about the world of computer networks (computer networking).