by Dinesh Thakur Category: Communication Networks

The purpose of error control is to ensure that the information received by the receiver is exactly the information transmitted by the sender. As the communication channel is highly unreliable, the receiver must be able to deal with the received data, if it contains error. The term error control is defined as the process of identification or correction of error occurred in the transmitted data. There are two types of error control mechanisms. They are:



 
by Dinesh Thakur Category: Communication Networks

Satellite radio, quite simply, is a non-terrestrial microwave transmission system utilizing a space relay station. Satellites have proved invaluable in extending the reach of voice, data, and video communications around the globe and into the most remote regions of the world. Exotic applications such as the Global Positioning System (GPS) would have been unthinkable without the benefit of satellites.

 
by Dinesh Thakur Category: Communication Networks

Generally, some people use the term "Ethernet" or ether refers to cable. Ethernet was the original product designed by Xerox PARC based on Bob Metcalfe's idea. It was later upgraded to 10 Mbps by Xerox, Intel and DEC.

 
by Dinesh Thakur Category: Communication Networks

In case of coaxial cables and twisted cable the maximum signal frequency, and hence the information rate that can be transmitted using a solid conductor is limited. Optical fiber differs from both these transmission media in that it carries the transmitted information in the' form of a fluctuating beam of light in a glass fiber rather than as an electrical signal on a wire. This type of transmission has become strong support for digital network owing to its high capacity and other factors favorable for digital communication.



 
by Dinesh Thakur Category: Communication Networks

Definition: Ethernet (pronounced "eether net") is a computer network technology which is used in different area networks like LAN, MAN, WAN. Ethernet connecting computers together with cable so the computers can share information. Within each main branch of the network, "Ethernet" can connect up to 1,024 personal computers and workstations.



 
by Dinesh Thakur Category: Communication Networks

Infrared light transmissions have existed for many years and their use having been limited to TV remote controls and wireless slide projector remote controls. However, they now are assuming a position of some, if still limited, importance. Infrared systems use the infrared light spectrum to send a focused light beam to a receiver, much, as would a microwave system, although no reflective dish is used. Rather, pair of lenses is used, with a focused lens employed in the transmitting device and a collective lens in the receiving device as shown in Figure. Infrared is an airwave, rather that a conducted transmission system. Although generally used in short-haul transmission, they do offer substantial bandwidth, but with risks of interference.

 
by Dinesh Thakur Category: Communication Networks

The notion of quality of service, or QoS, concerns certain characteristics of a network connection under the sole of the network service provider liability.

A QoS value applies to the whole of a network connection. It must be identical at both ends of the connection, even if it is supported by several interconnected subnetworks each offering different services.

 
by Dinesh Thakur Category: Communication Networks

Definition: Media access control (MAC) and logical link control (LLC) are the sublayers of the data link layer (Layer 2) in OSI Reference Model. 'MAC' is also refer to as MAC layer. It use MAC protocols to provides unique addressing identification and channel access control mechanism for network nodes to communicate with other nodes across a shared channel.



 
by Dinesh Thakur Category: Communication Networks

Like repeaters, bridges are used to connect similar LANs together, for example, Ethernet-to-Ethernet and operate at the bottom two layers of the OSI model, i.e. physical layer and data link layer. As it operates on second layer of the OSI model,' it relays only necessary data to other signals. MAC addresses (physical addresses) are used to determine whether data is necessary or not.

 
by Dinesh Thakur Category: Communication Networks

What is Hub: Another name of Hub is Ethernet Hub, Repeater Hub, Active Hub and Network Hub. Basically, it is a similar to switch but are not as "smart", 

Hub Definition and Meaning

hub in computer network is used for connecting multiple computers or segments of a LAN. Normally, it is used for Peer to Peer small Home Network. LAN Hub receive data packets (frames) through one port and broadcasts them through all other ports, so that all other computers or other network devices can see all packets.



 

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About Dinesh Thakur

Dinesh ThakurDinesh Thakur holds an B.SC (Computer Science), MCSE, MCDBA, CCNA, CCNP, A+, SCJP certifications. Dinesh authors the hugely popular blog. Where he writes how-to guides around Computer fundamental , computer software, Computer programming, and web apps. For any type of query or something that you think is missing, please feel free to Contact us.