The way computers are playing a very important role in our daily lives now, its all because of the intensive networking that goes behind it.
What is networking?
As the name suggests network is a group of computers which work together in a particular fashion. Based on the way they are connected they are classified accordingly. classification is mainly done on the type of connectivity they are providing and the area they are covering. A network helps the users to share information, files, softwares, and communications like e-mail, instant messaging, chat roomsvideo conferencing, among themselves without moving from their respective locations.
The first operational network in the world came up in the united states in 1960's. It was used for the UNITED STATES DEFENCE and was called the Advanced Research Projects Agency Network, in short (ARPANET).
For a computer network to become operational they must be first connected to each other, they can be either connected in a wired manner or a wireless method. The type of connection that exists between the nodes (computers), define the speed and connectivity that they share among themselves.
We can explain these connections in the following manner, based on their methodoogy, firstly we sahll discuss about the WIRED CONNECTIVITY:
TWISTED PAIR: Its is in comparision to the cable that is used to coonnect the computer to the internet, expect that two pairs of the copper wires are cross conneted. It is the most widely used connection type for few number of computers, it can carry upto 100mbps.
COAXIAL CABLE: It consists of two layers of wires wrapped together. One copper and the other alluminium. They ear mostly used for worksites. They can carry upto 500mbps.
OPTICAL FIBRE: These are the most advanced type of connectivity cables, they have glasss failments in a protective covering. They are mostly used to connect two internet between two or more nations, they carry data at high speeds of( tbps).
The othe way of connectivity that exists between the systems is WIRELESSLY:
TERRESTRIAL MICROWAVE: The receiving and transmitting systems are located on land, they use low frequency transmission and the relay stations are placed at regular distances.
COMMUNICATION SATELLITES: Satellites are sent into the space fro the purpose of transmitting data, these are called geosynchronous satellires(revolving at the equator), they orbil at a height of 22,000 km from the surface of earth and are capable of carrying voice , data and images.
BLUETOOTH: This is another familiar type of network, it uses a bluetooth interface that is wireless and is connected among two or more devices. It can be defined as a secure network because it uses a pre defined authentication between the devices. It can support upto 1mbps within a distance of 10-100m.
CELLULAR and PCS SYSTEMS: There are various types of cellular networks such as CDMA, GSM, GPRS, HSPDA. These are capable of carrying various types of data and through large distances.
WIRELESS LAN: Also knownas wi-fi, they run using radio frequencies at high frequencies, they are accessed using wi-fi compatible devices and are limited toa limited area, they are secured to seal any un-authorised access. The standard technology is IEEE 802.11b.
Based on the area they are stretcehed upon they are classified into the following:
Personal area network: It is used by a single person to connect the faxes, printers etc.. Local area network: it is used to connect a small building or ccomputers within the nearby premises. Home area network: These are typically deployed in houses Metropolitan area network:It is used between tow or more cities. Wide area network: It is used to cover a large physical area. Global area network: It is used for supporting communications through LANS. Enterprise Private Network: Used within an enterprise to conect their various branches. Virtual private network: These networks are run on virtual basis Internetwork: Made up of Private Networks Intranets and extranets: Extensions of LANS & WANS Overlay Network: They contain various types of networks working together. n my personnal view the computer networking is a very important and highly infuential topic and is a backbone for the entire system to run over. There are various hardware components that need to be used in, for the implication of the network. These can be enumerated as below:
NETWORK INTERFACE CARD (NIC): A compuetr needs to be connected to the other and it cannot be done without a medium. For this reason the NIC is used. This acts as a bridge between the two computers.
REPEATERS: They work something like an amplifier in a radio system. The raw data signal comes along with various dsturbances, these disturbances are then cleared and the actual system with the ccontent is increased in intensity and transmitted.
HUBS: As the name suggests, a hub is used to connect more number of cables to asingle system using a single port on the actual system withwhich the remaining ones have to interact.
BRIDGES: At the datalink level the various network segments are connecte dto one another, they are actuall y used to read the MAC address of the systems.
These are basically classified as:
- LOCAL BRIDGES
- REMOTE BRIDGES
- WIRELESS BRIDGES
SWITCHES: As the purpose of a switch in other circumstances, here it is used to shift between the datalayers of various protocols. These are used in the various topologies so as to shift from one end to the other.
ROUTER: this is considered to be one of the most vital and purpose serving instrument in the hardware part. It is used to basically to forward the packests of data based on their address in the header and the address of the next header they are supposed to carry with them.
The next important thing in a computer network is the protocol, actually a protocol is a predefined set of rules that are to be followed to establish a conection and to transfer the data. Not adhering to these significant issues the transfer is not under taken. The widely used protocols are:
IP (Internet Protocol)
UDP (User Datagram Protocol)
TCP (Transmission Control Protocol)
HTTP (Hypertext Transfer Protocol)
FTP (File Transfer Protocol)
POP3 (Post Office Protocol 3)
SMTP (Simple Mail Transfer Protocol)
With the huge number of computers that are operational around the world today and the ever multiplying number of them and the increasing need to a global hub to be interconnectd all the time is increasing the scope of computer networks. The best example would be the world shifting to IP v6 due to the completely filled addresses in Ipv4. Moreover, it s very install for induviduals to install a network in their premises without the help of a professional to do so, as many publications have made the process more easily undersatndable and implementable.