by Dinesh Thakur Category: Communication Networks

Another solution to obtain a broadband distribution network is to use the wiring of cable operators, when it exists. This wiring has long been made of CATV (cable TV), whose bandwidth exceeds 800MHz easily. Today, this infrastructure is slightly modified by the introduction of systems HFC (Hybrid Fiber/Coax), combining a fiber portion between the head end and the beginning of the service by the CATV. This topology is illustrated in Figure.

 
by Dinesh Thakur Category: Communication Networks

When the frames transmitted on the PON are Ethernet, EPON talking. The features of this network are identical to those of the other PON: distribution throughout the network, where only the station specified in the Ethernet frame can retrieve the information conveyed. The standardization of EPON technology is performed by the IEEE 802.3ah group. This group has several objectives, including that of introducing Ethernet in the local loop under the name of EFM (Ethernet in the First Mile). The objective was to replace the ATM technology, very expensive to implement on a multipoint technology, the Ethernet technology.



 
by Dinesh Thakur Category: Communication Networks

On the Passive Optical Network (PON), it is possible to transit ATM cells according to the technique developed by the working group FSAN (Full Service Access Network). This solution was then standardized in G.983 recommendation ITU-T. Both ends of the optical shaft are called OLT (Optical Line Termination) and ONU (optical network unit). For reasons of energy loss, it is not possible to exceed fifty branches on the trunk. The figure illustrates the architecture of a passive optical network.

 
by Dinesh Thakur Category: Communication Networks

The function of the network layer is to provide an end-to-end communication capability to the transport layer, which lies above it as shown in Figure. The OSI reference model specifies that the transport layer need not know the method by which the network layer performs communications.

 
by Dinesh Thakur Category: Communication Networks

The Ethernet frame is designed to transport packets in enterprise networks by an original method for broadcasting on a local network. This solution gave birth shared Ethernet, in which the broadcast frame is transmitted and where only the station that recognizes the right to copy the information. To this solution dissemination has added Ethernet switching.



 
by Dinesh Thakur Category: Communication Networks

How to encode the digital signal is an important function of coupler communication. This main function is to adapt the signals transmission channel. In the case of local networks, the transmission rate is tens or hundreds of megabits per second. Therefore, the choice of representation Physical data is important. To perform the synchronization bit, that is to say, to ensure that each bit is read at the right time, you need a minimum of transitions are made to extract the clock signal.

 
by Dinesh Thakur Category: Communication Networks

Before transmitting information on a transmission medium, it must be encoded of adequately. Networks must allow very high speeds over distances more or shorter. In this context, three approaches are possible for coding bits from applications:



 
by Dinesh Thakur Category: Communication Networks

ISO (International Standardization Organization) standard has its own architecture as the OSI (Open Systems Interconnection). The architecture ISO is the first to be defined, and so relatively parallel to the Internet. The distinction between the two is that the ISO formally defines the different layers architecture, while the Internet architecture is applied to achieve a practical environment.

 
by Dinesh Thakur Category: Communication Networks

The MAC layer is the "Brain" of WiFi. The first version of 802.11 (the 802.11 legacy published in 1997), defined the MAC layer by incorporating a number of features crucial, such as sharing of speech among users, the terms of network connection, error control or security.

 
by Dinesh Thakur Category: Communication Networks

Short communication

The infrared light is used for many years for the communication directly between nearby devices to each other, such as remote control and your television, for example.

 
by Dinesh Thakur Category: Communication Networks

The extension of the corporate network

Although there are a multitude of applications in WiFi technology, it is clear as its primary target is the corporate network. As we have seen, the WiFi was designed for a wireless version of Ethernet and the latter is found in almost all businesses. In most cases, a company that decides be equipped with a WiFi network already has a wired Ethernet network. It is therefore generally build a wireless extension to an existing wired network.

 
by Dinesh Thakur Category: Communication Networks

The transfer rate, or "data rate" refers to the speed with which data is transferred from its source to its destination, such as from one computer to another over a network, or from the computer to the disk drive. It's measured like we would measure any rate of speed-in units of information per the unit of time, like miles per hour. On a computer you may hear transfer rates expressed in terms like bits per second, megabytes per second, or characters per second.



 
by Dinesh Thakur Category: Communication Networks

Parity is a form of "error checking" where the computer checks to see if all the data it was supposed to get really did come through. You will most likely be confronted with parity when you use a telecommunications package to communicate through your modem. In fact, that's probably why you're reading this. The dialog box where you can set the serial port settings always wants to know the parity. The default setting is probably the safest thing to use if you don't know a reason to change it.



 
by Dinesh Thakur Category: Communication Networks

Half duplex means data can be relayed in only one direction at a time. Two-way transmission is possible, but the transmissions must be alternate. A walkie-talkie is half duplex-when one person is speaking, she cannot also listen A telephone is full duplex-information can go both ways simultaneously; both ends can talk and hear all the time-so does a modem.

 
by Dinesh Thakur Category: Communication Networks

EtherTalk is Apple Computer software that allows the Macintosh to hook into Ethernet networks. To use EtherTalk and Ethernet, the Mac must have the Ethernet interface card installed inside the computer.



 
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

From the early 1900s until now, long distance communication has primarily been in the form of the telephone line. Now telephone lines are being used for more than the transmission of voice; they are also used for the transmission of computer data. There are many reasons why someone might want to transfer data between one PC and another using phone lines.



 
by Dinesh Thakur Category: Communication Networks

Broadband ISDN (BISON) The next-generation of ISDN technology, with promised bandwidths from 150 megabits per second upward, sufficient to carry video-phone calls and movies. BISON will be carried over FIBRE-OPTIC cabling rather than wire, and the underlying transport protocol will be ASYNCHRONOUS TRANSFER MODE. Different implementations are planned in the USA, which will employ YNCHRONOUS OPTICAL NETWORK and Europe, which will use SYNCHRONOUS DIGITAL HIERARCHY.



 
by Dinesh Thakur Category: Communication Networks

Bit Error: An error in a single BIT within a BYTE or WORD of data transmitted over a noisy channel: for example if the byte sent was 11111111 then a received value of 11111101 would represent a bit error in the second bit. There are well-known ERROR DETECTION AND CORRECTION algorithms that can correct one or more such bit errors, given some extra, redundant information, and these techniques are widely applied in the mechanisms of HARDDISK and CD-ROM drives, as well as in telecommunication systems.



 
by Dinesh Thakur Category: Communication Networks

Let us examine the transmission technique that is to say how a transmitter can send a signal that the receiver will recognize as a 1 or a 0.

 

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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.