by Dinesh Thakur Category: Communication Networks

Analog is best explained by the transmission of signal such as sound or human speech, over an electrified copper wire. In its native form, human speech is an oscillatory disturbance in the air. Which varies in terms of its volume or power (amplitude) and its pitch or tone (frequency)? Analogous variations in electrical or radio waves are created in order to transmit the analog information signal for video or audio or both over a network from a transmitter (TV station or CATV source) to a receiver (TV set, computer connected with antenna). At the receiving end an approximation (analog) of the original information is presented.



 
by Dinesh Thakur Category: Communication Networks

IEEE 802.5 Token Ring: Token ring is the IEEE 802.5 standard for a token-passing ring in Communication networks. A ring consists of a collection of ring interfaces connected by point-to-point lines i.e. ring interface of one station is connected to the ring interfaces of its left station as well as right station. Internally, signals travel around the Communication network from one station to the next in a ring.

 
by Dinesh Thakur Category: Communication Networks

Computers are digital in nature. Computers process, store, and communicate information in binary form, i.e. in the combination of 1s and 0s which has specific meaning in computer language. A binary digit (bit) is an individual 1 or O. Multiple bit streams are used in a computer network.



 
by Dinesh Thakur Category: Communication Networks

Hubs/Repeaters are used to connect together two or more network segments of any media type. In larger design, signal quality begins to deteriorate as segment exceeds their maximum length. A hub provides the signal amplification required to allow a segment to be extended a greater distance.

 
by Dinesh Thakur Category: Communication Networks

Transmission is the method by which computer networks send electrical signals. Data communication is concerned with the process of exchanging data electronically between two communication devices. In a local area network, all communication functions are performed through direct cables. Computers located far away are connected through a special form of data communication link. The existing telephone or telegraphic network may also be used for connecting computers located at remote locations.



 
by Dinesh Thakur Category: Communication Networks

Definition: Optical fiber consists of thin glass fibres or plastic or any dielectric medium which can carry light signals from one end to the other. Optical fiber refers to the medium and the technology which is related, or you can say that it is connected with the transmission of information in the form of light impulses and this transmission is done along with a glass or plastic wire or fiber. The wires of fiber optic cable can carry much more information than any other conventional copper wire. The typical optical fiber consists of a very narrow strand of glass called the core. Around the core is a concentric layer of glass called the cladding.
Optical fibres make use of light to send information through the optical medium.



 
by Dinesh Thakur Category: Communication Networks

Bound Transmission Media in Communication Networks are the cables that are tangible or have physical existence and are limited by the physical geography. Also known as Conducted systems, wired media generally employ a metallic or glass conductor which serves to conduct, some form of electromagnetic energy.

 
by Dinesh Thakur Category: Communication Networks

Microwave radio, a form of radio transmission that use. Ultra-high frequencies developed out of experiments with radar (radio detecting and ranging) during the period preceding World War II. There are several frequency ranges assigned to microwave systems, all of which are in the Giga Hertz (GHz) range and the wavelength in the millimeter range. This very short wavelength gives rise to the term microwave. Such high frequency signals are especially susceptible to attenuation and, therefore must be amplified or repeated after a particular distance.

 
by Dinesh Thakur Category: Communication Networks

When data is being transmitted from one machine to another, it may be possible that data become corrupted on its, way. Some of the bits may be altered, damaged or lost during transmission. Such a condition is known as error.

 
by Dinesh Thakur Category: Communication Networks

RS-232C is a long-established standard ("C" is the current version) that describes the physical interface and protocol for relatively low-speed serial data communication Networks between computers and related devices.



 
by Dinesh Thakur Category: Communication Networks

Unbound transmission media extend beyond the limiting confines of cabling. They provide an excellent Communication Networks alternative for WANS. The lack of physical restrictions provides larger bandwidth as well as wide area capabilities. Unbound media typically operate at very high frequencies. The three types of unbound transmission media are: Radio wave, Micro wave, Infrared.



 
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

Data is transmitted between communication devices in multiples of fixed-length units, typically 8-bits. For example, if the computer is transferring a source program, the data will be made up of a block of 8-bit binary-encoded characters. On the other hand, if the data is in the form of a compiled object code of the program, the data will be made up of a block of 8-bit bytes. At the receiving end, the following parameters are determined to decode and interpret the message correctly.



 
by Dinesh Thakur Category: Communication Networks

This may be considered as the breakthrough for many of current ideas, algorithms and Internet technologies. It started Paul Baran in 1960s funded by Advanced Research Projects Agency (ARPA), an organization of the united States Defense Department and, therefore, named as Advanced Research Projects Agency Network (ARPANET) predecessor of the modern Internet. It was world's first fully operational packet switching computer network and the world's first successful computer network to implement the TCP/IP reference model that was used earlier by ARPANET, before being used in the Internet. The ARPANET is the first network that planed the seed of interent.



 
by Dinesh Thakur Category: Communication Networks

It is required that information must be encoded into signals before it can be transported across communication media. In more precise words we may say that the waveform pattern of voltage or current used to represent the 1s and 0s of a digital signal on a transmission link is called digital to digital line encoding. There are different encoding schemes available:



 
by Dinesh Thakur Category: Communication Networks

Radio waves, also called radio waves as they were discovered by German physicist Heinrich Hertz in 1888, are electromagnetic waves, that is to say the combined oscillation of an electric field and a magnetic field. Radio waves, infrared, visible light, ultraviolet, X-rays or gamma rays are all examples of electromagnetic waves.

 
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

Broadband A communications medium that can carry a wide range of signal frequencies, typically from audio up to video frequencies. In telecommunications the significance of a broadband system is that it can carry television and videoconferencing data as well as voice calls. A broadband medium can be made to carry many signals at once by apportioning its total bandwidth into many independent channels, each of which carries only a specific range of frequencies. In contrast, a BASEBAND can carry only a single channel. ATM, ADSL and Cable TV are all broadband media, while standard ISDN barely qualifies.

 
by Dinesh Thakur Category: Communication Networks

Routers are used to connect both similar and dissimilar LANs. Router operates on the network layer of OSI model using the physical layer, data link layer and network layer to provide connectivity, addressing and switching. These are highly intelligent devices. In case of TCP/IP network, Internet Protocol (IP) is used as addresses for network; this is the router which interprets the IP address and delivers the packet reliably.

 
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.