Tuesday, January 1, 2019
Saturday, December 8, 2018
Transmission Media
Network Infotech
Saturday, December 08, 2018
A transmission media can be defined as anything
that can carry information from a source to a destination
On the basis of transmission of data, the transmission media can be classified in to two categories:
1) Guided (Physical) transmission media
2) Unguided (Wireless) transmission media
1) Guided Transmission Media:
Guided media are those that provide a channel from one device to another.
The three Guided (Physical) media commonly used for data transmission are:
1. Twisted-Pair
2. Coaxial
3. Fiber Optics
1. Radio Transmission
2. Microwave Transmission
3. Infrared
4. Light wave Transmission
On the basis of transmission of data, the transmission media can be classified in to two categories:
1) Guided (Physical) transmission media
2) Unguided (Wireless) transmission media
1) Guided Transmission Media:
Guided media are those that provide a channel from one device to another.
The three Guided (Physical) media commonly used for data transmission are:
1. Twisted-Pair
2. Coaxial
3. Fiber Optics
2) Unguided
(Wireless) transmission media:
Unguided media transport electromagnetic waves without using
a physical conductor. This type of communication is often referred to as
wireless communication.
1. Radio Transmission
2. Microwave Transmission
3. Infrared
4. Light wave Transmission
Friday, November 30, 2018
Internet
Network Infotech
Friday, November 30, 2018
The internet is a type of world-wide computer network.
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The internet is the collection of infinite numbers of connected computers that are spread across the world.
We can also say that the Internet is a computer network that interconnects hundreds of millions of computing devices throughout the world.
It is established as the largest network and sometimes called a network of the network that consists of numerous academic, business and government networks, which together carry various information.
The Internet is a global computer network providing a variety of information and communication facilities, consisting of interconnected networks using standardized communication protocols.
When two computers are connected over the Internet, they can send and receive all kinds of information such as text, graphics, voice, video, and computer programs.
Tuesday, November 27, 2018
Types of Network
Network Infotech
Tuesday, November 27, 2018
1. LAN (Local Area Network):
It is privately-owned networks within a single building or campus of up to a few kilometres in size.
They are widely used to connect personal computers and workstations in company offices and factories to share resources (e.g., printers) and exchange information.
LANs are easy to design and troubleshoot.
In LAN, all the machines are connected to a single cable.
Different types of topologies such as Bus, Ring, Star and Tree are used.
The data transfer rates for LAN is up to 10 Gbits/s.
They transfer data at high speeds. High transmission rate are possible in LAN because of the short distance between various computer networks.
They exist in a limited geographical area.
Advantages ::
LAN transfers data at high speed.
LAN technology is generally less expensive.
2. MAN (Metropolitan Area Network):
MAN is a larger version of LAN which covers an area that is larger than the covered by LAN but smaller than the area covered by WAN.
A metropolitan area network or MAN covers a city. The best-known example of a MAN is the cable television network available in many cities.
MAN connects two or more LANs.
At first, the companies began jumping into the business, getting contracts from city governments to wire up an entire city.
The next step was television programming and even entire channels designed for cable only.
3. WAN (Wide Area Network):
WAN spans a large geographical area, often a country or region.
WAN links different metropolitan’s countries and national boundaries there by enabling easy communication.
It may be located entirely with in a state or a country or it may be interconnected around the world.
It contains a collection of machines intended for running user (i.e., application) programs. We will follow traditional usage and call these machines hosts.
The communication between different users of WAN is established using leased telephone lines or satellite links and similar channels.
It is privately-owned networks within a single building or campus of up to a few kilometres in size.
They are widely used to connect personal computers and workstations in company offices and factories to share resources (e.g., printers) and exchange information.
LANs are easy to design and troubleshoot.
In LAN, all the machines are connected to a single cable.
Different types of topologies such as Bus, Ring, Star and Tree are used.
The data transfer rates for LAN is up to 10 Gbits/s.
They transfer data at high speeds. High transmission rate are possible in LAN because of the short distance between various computer networks.
They exist in a limited geographical area.
Advantages ::
LAN transfers data at high speed.
LAN technology is generally less expensive.
2. MAN (Metropolitan Area Network):
MAN is a larger version of LAN which covers an area that is larger than the covered by LAN but smaller than the area covered by WAN.
A metropolitan area network or MAN covers a city. The best-known example of a MAN is the cable television network available in many cities.
MAN connects two or more LANs.
At first, the companies began jumping into the business, getting contracts from city governments to wire up an entire city.
The next step was television programming and even entire channels designed for cable only.
3. WAN (Wide Area Network):
WAN spans a large geographical area, often a country or region.
WAN links different metropolitan’s countries and national boundaries there by enabling easy communication.
It may be located entirely with in a state or a country or it may be interconnected around the world.
It contains a collection of machines intended for running user (i.e., application) programs. We will follow traditional usage and call these machines hosts.
The communication between different users of WAN is established using leased telephone lines or satellite links and similar channels.