ELEMENTS OF A NETWORK

SERVER: it is the main processing element, it contains the network operating system and is responsible for managing all the processes within it, it also controls access to common resources such as printers and storage units.



WORKSTATIONS: sometimes called nodes, they can be personal computers or any terminal connected to the network. You work with your own programs or take advantage of existing applications on the server.

NETWORK OPERATING SYSTEM: it is the program that allows the control of the network and resides in the server.

COMMUNICATION PROTOCOLS: they are a set of rules that regulate the transmission and reception of data within a network.

NETWORK INTERFACE CARD: provides the connectivity of the terminal or user of the physical network, since it handles the communication protocols of each specific topology.

WIRING: is the cable that is going to be used in the network that is physical is called utp.

HUB OR CONCENTRATOR: in communications, distribution center, hub. A Hub is a network device that allows other computers or devices to connect to each other by retransmitting data packets from any of them to everyone. They have stopped being used because of the large number of collisions and network traffic they produce.

  SWITCH: it is a digital device of interconnection logic of computer networks that operates in layer 2 (data link level) of the osi model: its function is to interconnect 2 or more network segments, similar to bridges (bridges), passing data from one segment to another according to the Mac address of different frames in the network.

 The switches are used when you want to connect multiple networks, merging them into one. Like bridges, since they function as a filter in the network, they improve the performance and security of the lans.



REPEATER: it is an electronic device that receives a weak or low level signal and retransmits it to a higher power or level, so that longer distances can be covered without degradation or with tolerable degradation. The term repeater was created with telegraphy and referred to an electromechanical device used to regenerate telegraphic signals. The use of the term has continued in telephony and data transmission.

BRIDGE : it is a computer network interconnection device that operates in layer2 (data link level) of the osi model. It interconnects 2 network segments by passing data from one network to another, based on the physical destination address of each package. A bridge connects 2 network segments as a single network using the same network establishment protocol. It works through a table of Mac addresses detected in each segment to which it is connected. When it detects that a node of one of the segments is trying to transmit data to a node of the other, the bridge copies the frame for the other subnet. By using this machine learning mechanism, bridges do not need manual configuration.

The main difference between a bridge and a hub is that the second passes any frame with any destination for all other connected nodes, instead the first only passes frames belonging to each segment. This feature improves network performance by reducing useless traffic.

To make the bridging or interconnection of more than 2 networks, the switches are used.


ROUTER: It is a general purpose device designed to segment the network, with the idea of ​​limiting brodcast traffic and providing security, control and redundancy between individual brodcast domains, it can also provide firewall service and economic access to a WAN. It operates in layer 3 of the osi model and has more software facilities than a switch. When operating on a layer greater than that of the switch, the router distinguishes between different network protocols, such as ip, ipx, apple talk or decnet. This allows you to make a smarter decision than the switch, when forwarding packets.



GATEWAY: A device that is frequently a computer, which allows networks to be interconnected with protocols and different architectures at all levels of communication. Its purpose is to translate the protocol information used in a network to the protocol used in the destination network.

The IP address of a Gateway (or gateway) often resembles 191.167.1.1 or 191.166.0.1 and uses some predefined ranges, 127 xxx, 10 xxx, 172 xxx, 192 xxx, which encompass or reserve networks local, also it should be noted that necessarily a team that fulfills the role of gateway in a network, must have 2 network cards.

 MODEM: It is a device used to modulate and demodulate a signal called carrier by another input signal called modulator. The modulating signal constitutes the information that is prepared for a transmission (a modem prepares the information to be transmitted, but does not perform the transmission). The modulator modifies some characteristic of the potador so that a signal is obtained, which includes the information of the modulator. Thus the demodulator can recover the modulating signal can recover the original modulating signal, removing the carrier. The characteristics that can be modified from the carrier signal are:

• Amplitude, resulting in an amplitude modulation (am / ask).

• Frequency, resulting in a frequency modulation (fm / fsk).

• Phase, resulting in a phase modulation (pm / psk).