The modern world of advanced technologies does not even appear without communication equipment. Because in almost every house, office, enterprise, educational institution there is a computer or even several, which means the Internet, and as a result, the network.
Indeed, the main function of communication equipment is the adoption, sometimes processing and transmission of data over a distance (from a few centimeters to several thousand kilometers).
Earlier, very common varieties of such devices were: a corded telephone, a telegraph ... A bit later, a fax.
Scientific and technical definition and types of equipment
Communication equipment - these are special devices that transmit any data on certain lines called communication lines (cable, switch, and others).
The most common varieties of these are fiber optic cable, twisted pair cable, coaxial cable.
What are the types of communication equipment?
- Data equipment or terminal.
- Network hardware.
- Communication line equipment.
Decoding of each type
All representatives of each type can also be called technical means of communication equipment.
Data equipment is a device that converts user information into data intended for transmission over a communication line, and performs the inverse transformation. This type of device includes personal computers, as well as a large electronic computer, a data acquisition device, a cash register and other terminal devices.
Network communication equipment is a technique that is necessary for computer networks to work. The most prominent representatives of this type are: switch, patch panel, router, hub, network adapter, repeater and others. There are two main types of equipment: active and passive.
Communication line equipment is a device that converts data that is generated by a special encryption device into a signal transmitted along these lines and performing the inverse conversion. The most recognizable and bright representative of this equipment is a modem.
Active network equipment
These are devices containing electronic circuits that operate from electrical networks (or other similar sources). These devices perform the function of amplifying and converting the signal to others.
In such equipment, the ability to process signals according to special algorithms is already inherently laid down. Namely: these devices not only capture and transmit signals, but also process the technical information given to them, redirecting and distributing the streams arriving to them according to the algorithms built into the equipment’s memory.
The equipment includes: a network adapter, a repeater (repeats the signal in order to increase the length of its propagation), a hub (also called a multi-port repeater), a switch (a device with several ports), a router (the same router), a relay, a media converter, a network transceiver (to transform the information transfer interface).
Passive Network Equipment
Passive is called such equipment, which is used for distribution, as well as reducing the signal level. It works without power from an electrical network or other similar source.
The most prominent representatives of this type of equipment are:
- cable system;
- cable routing equipment.
Local networks
The communication equipment of local area networks is the equipment that serves to interconnect devices into a single network. And this is necessary to create and connect multiple networks or subnets.
The equipment used in them is used to connect a separate node, and to communicate a large number of them with each other.
A type of local network that is very familiar to everyone is a computer network, which is a set of machines interconnected and equipped with special programs that provide network users with the ability to access all data of these computers.
Local networks are systems whose signal propagation is carried out in a radius of up to 3 kilometers. There is a network of departments, corporate (if in the same building), inside the school, as well as home.
There are also city networks (within the radius of a large city) and global (signal distribution in the territory of a city, region, country). But they are no longer local.
Corporate network
A very common local area network is the corporate network, which combines systems located throughout the enterprise. The number of jobs is one hundred or more.
If the organizational units are at a great distance from each other, then they use global network technologies.
In a corporate network, as a rule, rather high requirements for reliability and performance.
The interaction of the components of a computer system occurs according to schemes that may differ slightly from each other.
In addition, there are such components of such a network:
- Computers connected to the system are called stations or nodes.
- The presence of a network adapter - a device for connecting to the computer’s system bus and providing reception, as well as information transfer through the communication line.
- Twisted pair, which consists of several twisted strands of copper wire.
- A coaxial cable consists of an insulated copper wire, an insulating braid, and an outer sheath (it can, unlike a twisted pair cable, transmit information over longer distances).
- Fiber optic cable (the signal passes through it best).
- Computers that are designed to serve other computers are called servers.
- Those that make requests to the resource base of other computers are called client nodes.
- If one computer combines both functions in one, then it is called a peer.
The principles of building a computer network
Network topologies are the connection diagrams of physical components that are determined by the logical structure of the network itself.
It happens:
- fully connected;
- cellular;
- type "star";
- "Common bus";
- roundabout;
- tree-like.
With a fully connected network topology, each machine is directly connected to the others.
Cellular - this is when several possible connections are removed from a fully connected one.
A star topology is formed when each individual machine is connected via a separate cable to a common central unit.
There are several types of “stars”: with distributed control and with a central one.
Star Technology: All nodes connect to a single cable with 2 open ends. And only one node at a given point in time has the ability to send information. The signal travels in both directions. At the same time, any of the nodes has the ability to access the transmitted data. At the ends of the bus are installed such special devices - “terminators” that suppress the signal.
The “common bus" is also another type of "star" when the central device is a passive cable.
In a ring topology, information is transmitted from one machine to another - in a ring.
The most difficult is the tree topology, where the root of the "tree" is the central redirection device. The main cable is connected to it. And already to it - several network. The frequency of the data is changing. Frequency conversion is carried out at the root of the tree.
Network technology
Technologies for transmitting information on the network are carried out on the basis of a set of rules and protocols governing message addressing and packaging for transmission over the network.
The set of these protocols, as well as the software and hardware implementing them , is called network technology.
Cell Amplifiers
A person in modern life cannot even imagine a day without a mobile or cell phone. It helps in communicating with loved ones, friends, and at work. In general, a large number of advantages.
Cellular communications may not be well picked up by the phone everywhere. This is especially true for remote areas (suburbs).
And therefore, in such places, communication representatives install cellular signal amplifiers, which also applies to the communication equipment considered in the article.
This is a certain system, which consists of an external antenna (receiving and transmitting a signal to a base station), a repeater (directly an amplifier), an internal antenna (thanks to it there is a signal in the room) and a cable.
Summary
To summarize the information article, which, perhaps, does not so deeply cover the topic of what relates to communication equipment. There are no more precise and specific technical and technological details.
And only the most basic concepts are considered and the basic technical means of computer networks are described, thanks to which data is transferred.
The rest of the deeper information regarding communication equipment can be clarified in the specialized literature.