of networks is the sharing of resources (data , software and devices peripherals such as printers, modems, fax machines, tape drives, hard drives and other equipment for data storage) among a group of computers. A network can be as small as two computers connected by a cable or so large that connect hundreds of computers and peripheral devices in various configurations.
When IBM introduced in 1981, the personal computer (PC), personal word was a proper adjective. It was addressed to those who wished to have your own computer, on which run their own applications, and they manage their personal files instead of using minicomputers and mainframes that were under the strict control of the departments computer. The personal computer users soon began to connect their systems in networks, in a way they can share resources like printers. Then something funny happening. Around 1985, the networks became so large and complex control returned to the departments. Today the networks are not simple and easy items. They often come to extend outside the local office, covering the environment of a city or a longer time and need experts who can address the problems of telephone communications via satellites or microwave
The simplest network connecting two computers, allowing them to share files and print. A more complex network connecting all the computers in an enterprise or company in the world. To share printers just a switch, but if you want to share files and run applications efficiently network, you need network interface cards (NIC, NetWare Interface Cards) and cables to connect the systems. Although you can use various network systems via serial and parallel ports, these inexpensive systems do not offer the speed and integrity who need a secure network operating system and high performance that enables to manage many users and recursos.lite
A computer network is connected both hardware and software. The hardware includes both network interface cards and cables that connect them, and the software includes the drivers (programs that are used to manage the devices and the network operating system that manages the network). The following lists the components as shown in Figure 2.1: Server
Workstation Motherboards Network Interface (NIC) and shared peripherals Resources
A repeater is an A repeater is an electronic device that receives a signal weak or low level and transmits at a power level or higher, so that they can cover longer distances without degradation or with a tolerable degradation
The term repeater was created with the telegraph and referred to an electromechanical device used to regenerate telegraph signals. The use of the term has continued in telephony and transmission of data . A repeater is an electronic device that receives a signal weak or low level and transmits at a power level or higher, so that they can cover longer distances without degradation or tolerable degradation.
The term repeater is created with the telegraphy and referred to an electromechanical device used to regenerate telegraph signals. The use of the term has continued in telephony and transmission of data .
telecommunications the term repeater has the following standard meanings: A device analog that amplifies an input signal, regardless of its nature (analog or digital).
A digital device which amplifies, shapes, retemporiza or performs a combination of any of these functions on an input digital signal for transmission.
In the reference model OSI the repeater operates in the physical level .
For digital signals the repeater is usually called regenerative because, in fact, the output signal is a signal regenerated from the input.
Repeaters are often used in the cables transcontinental and transoceanic since attenuation (signal loss) in these distances would be completely unacceptable without them. Repeaters are used in both copper cables carry electrical signals such as cable fiber carrying light.
0 comments:
Post a Comment