At present, it is almost impossible to think of a world where computer networks do not exist, since over the years they have become absolutely essential for everything to function as it should, from hospitals and shopping centers, to the most great of the networks: Internet.
At first, computer networks were used in a limited number of applications, most of them military or scientific, but their use has expanded from this area to the office, industry and home, resulting in the creation of various types of networks, each adapted to the specific needs of the environment.
In this post we will find information and characteristics about the main types of networks that we access in our daily work, perhaps even without realizing it.
LAN, WAN, MAN, WLAN, WMAN, WWMAN, SAN and PAN: What does each term mean?
Most common types of networks
LAN (Local Area Network)
The Local Area Network (LAN), or by its translation into Spanish Local Area Networks, are the most widespread type of network, being used primarily for the exchange of data and resources between computers located in a relatively small space, such as a building or group of them, such as educational or government institutions and even in our own home.
However, a LAN can be connected to other local area networks regardless of the distance, since it uses other mechanisms, such as data transmission by radio and others. This is called WAN or Wide Area Network, as we can see further down in this article.
Undoubtedly, the most significant characteristic of the LAN is that it allows the interconnection of multiple nodes or individual computers, to access the data and resources they have, that is, we can use printers, storage units and other devices even when not are physically connected to our computer.
Another characteristic of LANs is that they transmit data to each other at very high speed, however the distances at which they can do so is limited, as well as the number of nodes that can be connected to a single LAN.
WAN (Wide Area Network) network
Called Wide Area Network , or WAN (Wide Area Network) and is also known is basically one or more LANs interconnected to cover much more territory, sometimes, even continents.
The networks WAN are mostly used by large companies for their own use, while others are used by WAN ISP to provide Internet service to its customers . Computers connected through a Wide Area Network or WAN are generally connected through public networks such as the telephone system, however they can also use satellites and other mechanisms.
MAN Network (Metropolitan Area Network)
MAN or Metropolitan Area Network , whose translation into Spanish is Red de Area Metropolitana, is a data network specifically designed to be used in areas of cities or towns. The first characteristic, speaking in terms of geographic coverage, is that Metropolitan Area Networks or MANs are larger than local area networks or LANs , but smaller in geographic scope than wide area networks (WANs).
MAN are characterized by very high-speed connections using fiber optic cable or other digital media, which allows it to have a much lower error rate and latency than other networks armed with other types of conductors. They are also very stable and resistant to radio-electric interference.
This fact makes metropolitan area networks very suitable for multimedia traffic environments, which allows, among other things, to implement surveillance systems through video cameras with a very significant cost / benefit ratio.
WLAN (Wireless Local Network) network
A Wireless Local Area Network, better known as WLAN , is basically a data transfer and communications system which does not require that the computers that compose it have to be wired together, since all data traffic between them is performed through radio waves.
Although they are less secure than their wired counterpart, they offer a wide variety of advantages, and that is why their implementation grows day by day in all areas.
However, the most outstanding characteristic of wireless networks is the savings in the laying of cables for the interconnection of the PCs and devices that compose it, since it does not require any cable for its interconnection, a great advantage for the home , the office and SMEs.
WMAN (Wireless Metropolitan Network) network
In very basic terms, the WMAN or Red Metropolitana Inalámbrica for its translation into Spanish, is a wireless version of MAN , which can have a range of tens of kilometers. This technology uses techniques based on the WiMAX (Worldwide Interoperability for Microwave Access) communications standard .
Network WWAN (Wireless Local Area Network)
Wireless WAN or Wide Area Wireless Network is a network that is capable of providing wireless coverage in a relatively large geographic area. Basically, a WWAN differs from a Wireless Local Area Network or WLAN in that the former uses cellular network technologies for mobile communications such as WiMAX, UMTS, GPRS, EDGE, CDMA2000, GSM, CDPD, Mobitex, HSPA and 3G to perform the data transfer between the nodes that make up the network. It may also be that we find the possibility of using LMDS and autonomous Wi-Fi to access the internet.
Network SAN (Storage Area Network)
A SAN or Storage Area Network, which translated into Spanish means the storage area network, is a technology widely used by large companies to obtain greater flexibility in obtaining and handling the data it needs for its development.
Basically, a SAN is a network made up of storage units that are connected to companies’ local area networks, and the main characteristic, without going into overly complicated technicalities, is that they are capable of unlimited growth, so It can offer its operator incredible storage capacities of up to thousands of TB.
Red PAN (Personal Area Network)
A PAN network , abbreviation of the English Personal Area Network, and whose translation into Spanish means Personal Area Network, is basically a network made up of all the devices in the local and close environment of its user, that is , it is made up of all the devices that they are close to it. The main characteristic of this type of network that allows the user to establish communication with their devices in a simple, practical and fast way.
Currently there are several technologies that allow the creation of a personal area network, including Bluetooth and systems that use infrared transmission to communicate.
How to fix the most common network problems
Thanks to the possibilities and flexibility that computer networks offer us, the work we do daily with them was simplified and allowed us to do more or rest less, depending on the way we look at it. However, as with any other complex implementation, the more are the benefits, the more problems we may have.
Let us remember that several devices and many meters of cable interact with their respective connectors and accessories in a network, in addition to the software configurations to keep them working, and it is always possible that some problem may arise, leaving any of its nodes without working in complete isolation from the other computers.
From this point on, we will know the best tips and guidelines to follow when we have problems with the network, which will be very useful for any damage that is not greater and not having to depend on specialized technicians who will surely charge us a good amount for something that we can repair ourselves.
Wrong cable, poorly made or bad connector
One of the main causes for a computer network to function incorrectly is its most basic part, that is, the physical connection. A cable in bad condition or simply poorly seated in its connector is the probable cause of 90% of the problems that can be had in a network.
Although this type of network connectors have been designed and manufactured to fit perfectly, sometimes it often happens that sudden movements disconnect them. They may also not work due to connector contact failure, which may be dirty or oxidized.
If we suspect that something of this may have occurred, the best way to solve this problem is to disconnect the cable and check if the cable has any of the problems described, among other checks such as those shown in this link.
In the event that the network connectors are loose, adjust them, and if they are dirty or rusty, there is no alternative but to change the network connector for a new one or repair it , in the event that we have the necessary skills and instruments.
Mains board burned or malfunctioning
There is no doubt that if we notice that one of the network cards of any of the computers has failed it is one of the most frustrating news that we can receive, especially if our network has several computers. Fortunately, knowing if a network card or motherboard has burned out is relatively easy.
To do this, we check that everything is correctly installed and working, and then we carefully observe the network card to see if it works, seeing if any of its LEDs turn on or blink.
However, this is not necessarily good news, since it is possible that the lights turn on but that it does not transmit or receive data, the main indicator that the network card is not working correctly is that it is not recognized by the operating system.
So, if we have already verified that the network card is correctly wired, the network structure sends and receives data and its drivers are properly installed, but we cannot communicate that PC with the others on the network, it is more than Surely the plate has been damaged, so it is time to replace it with a new one.
Switch burned out due to electrical problems
No matter how careful we take with electronic components, mounting voltage stabilizers or even uninterruptible power supplies (UPS), electricity always manages to play a trick on us and leave some of our expensive equipment useless.
In the case of the switches, if we suspect that it may have been attacked by an electrical shock, the first thing we have to check to see if it is still in good working order is to look at the physical panel of the same, or in the event that it does not have For this convenience, access the device through a browser.
Of course, if the network switch has been burned out or completely damaged, it won’t turn on any of its lights. But in the event that the device does turn on its lights and behaves in an apparently normal way, but we still have problems accessing some of the PCs in our network through the device, there is a possibility that the switch is damaged. , although not entirely. Of course the solution to this problem is to buy a new switch , a quick but not painless solution.
In the event that everything works correctly, but we have certain problems such as a bad ignition or persistent unit resets, we can also check the outlet to which the unit is plugged to check if there is an electrical problem in it.
The range of the wireless network is not adequate
As we know, Wi-FI wireless networks are practical to install and very easy to use and configure, however, they tend to have range problems, and due to the type of environment in which they are used, they are subject to all kinds of interference.
Wi-Fi networks, when mounted by radio waves, are very sensitive to all the elements that they encounter in their path such as walls, furniture and others, their quality degrading as they cross obstacles.
If we verify that the range of the wireless network is not adequate even though it is in the minimum effective transmission and reception area , it is most likely that we have problems with interference.
In this sense, the first thing we have to do to solve the problem is of course to clear the path of the signal . For this we must make sure that between the wireless router and the computers and devices to be reached there are no thick walls, cordless telephones, microwave ovens, or any other device that with its signals can limit the Wi-Fi range.
Unfortunately, in the case of only walls, we can do nothing, except change the location of the wireless router. It is also possible to add signal repeaters, with which we will surely solve the problem.
Now, to fix problems caused by interference with other devices, it would be best to place them as far away from the wireless network as possible.
What is a network adapter?
In the event that our network card has suffered damage due to an electrical problem, we can always get to work without problems thanks to the so-called network adapters. Basically, a network adapter allows us to replace an internal network card in the event of any problem, and they can be designed to adapt to any network situation, that is, there are models for both wired Ethernet and wireless networks by WiFi.
In this sense, a network adapter designed to be used in a wired Ethernet network is basically a dongle that connects to a USB port that offers an Ethernet port, that is, an RJ45 connector.
Generally, this type of adapter includes a disk with its own drivers in the package, but most of the time its installation is not necessary, since the operating systems, as soon as we connect the adapter to the USB port, will take care of installing the necessary without the user having to participate in the process.
When the system has successfully installed the device, it is ready to be used. The only thing we have to do to connect to an Ethernet network or to the Internet is to plug in the corresponding network cable.
The other type of network adapter on the market is the one used in wireless networks. This type of network adapters are very useful for all those slightly older notebooks and mobile devices that do not have wireless connectivity, since this dongle will allow us to have the possibility of connecting to the Internet anywhere we are , without the need to be tied to a network cable.
In this sense we must be careful, since the WiFi standards are changing, since if we buy a wireless network adapter that supports only old standards, we will most likely have many connection problems. To be sure that we are making a good purchase, it is best to make sure that the adapter in some part of its packaging or description ensures that it is compatible with the 802.11b / g / n standard.
Basically, a wireless network adapter is a lot like a USB stick. As soon as we connect it to a USB port and the operating system detects and installs it, it will start working looking for all the WiFi signals that are in the vicinity. From this point on, the operating system will show us all available WiFi networks, after which we will be able to connect to them, as long as we have a username and password to do so.
Network problems due to software
If everything that we have previously tried has not been able to solve the problem we had with the network and we still cannot communicate the computers with each other, with all the elements such as connectors, cables and others in good condition, as well as a correct network topography , the solution may be found via software.
In this sense, one of the problems that we could have is that some of the computers that make up the network are configured for a different workgroup.
If we are on Windows, we can check this through the network icon on the task bar, by clicking on “Network and Sharing Center”. Once there we check if we are joined to the same working group.
These days, the word “networks” has become very frequent among those of us who use computers, and although it can be related to different areas related to computing, such as social networks, the truth is that when we talk about networks computing we mean a much broader platform.
Thanks to the millions of computers scattered around the world today we can, among other things, enjoy the Internet, because the truth is that if computer networks had not been invented today we could not be browsing the great network of networks.
The truth is that when we want to begin to know what computer networks consist of, we find that these networks are extremely complex, however we can have an idea about what they are and how they work through a series of basic concepts about computer networks, since in short it is mainly about the link that exists between computers so that they can communicate with each other.
Here we tell you precisely what a computer network is and how it works, and we also bring you some information about the types of computer networks that exist today. Let’s take a look!
What is a computer network?
For those who are unfamiliar with the world of computer networks, it is important to know in principle that one of the first computer networks to be used in packet switching was developed in the mid-sixties by the ArpaNet company, after which it was established that the first message sent through this platform took place on October 29, 1969. This is known as the precursor of what we know today as the Internet.
Now, let’s get to know how computer networks work. As we well know, with our computer we can perform the most diverse tasks, and as we add peripherals, including printers, scanners, modems and others, the functionalities of our PC expand even more.
Having this concept of communication between a computer and its peripherals, we can get a little closer to the concept of computer networks , since ultimately a computer network is a set of PCs that are connected to each other through different elements, that is, they can be connected by cables, optical fibers, wireless links or others.
Each of these computers separately are known as “nodes”, and their connection with other computers causes the formation of a computer network, in which all the computers that compose it can communicate with each other to carry out an exchange of data.
So, basically a computer network is nothing more than a set of computers, also including servers, network devices, peripherals, and other devices connected to each other, which have the particularity that when connected they can exchange data.
The best example of what a computer network is today is the Internet , a platform that allows millions of people around the world to connect and exchange data.
Objective of a computer network
It is important to note here that computer networks must respect certain established rules, and at the same time all the devices that make up a network must also respect certain rules, which are called protocols. This allows computers on a computer network to communicate with each other simultaneously.
In this way we can connect, for example, without inconvenience to the network of networks, the Internet, for which our computer must follow a series of protocols, which we do not see, in order to have access to the Internet. With this we can access the millions of web pages that exist, which are ultimately files stored on other computers , which are called servers, and which are distributed throughout the network.
Of course, accessing files does not imply that through the Internet we can have access to the personal files that other people store on their computers, since everything related to the computers that act as servers, as well as the protocols, works here. computer security.
For this reason, everything that refers to permissions and security are fundamental elements for the creation of networks, since basically we cannot have access to files and share resources if we do not have the permission to do so.
So, when we talk about personal computers, when they are connected to the internet they use what are called outgoing connections, that is, they allow access to other computers, which are the servers, but not to enter the personal PC of the person who is connected, since that incoming connections are blocked.
However, these days we have frequently heard the word hacking, which is nothing more than unauthorized people who evade security and access computer networks and computers to which they should not have access. To avoid this, it is extremely important to use software that allows us to protect our computer every time we connect to the internet.
Now, how does it work and what is the goal of a computer network?
The first thing to clarify here is that for a computer network to exist, there must be nodes that are connected to each other , either temporarily or permanently. One of the most widely used methods for this today is wireless connections, used mainly in home networks.
In this way, computers or nodes can connect and communicate with each other, through computer networks, in order to exchange data, which is ultimately the main goal of current computer networks.
The truth is that without knowing it, every time we surf the Internet, enter Facebook, or use an online application to, for example, listen to music, we are making our computer connect to one of the largest computer networks. In addition, when we do this with our smartphone or tablet, the same thing happens, since in this case the smartphone fulfills the same role as our PC.
Components of a computer network
As we have seen, in computer networks, the computers that compose them can share devices, functions and characteristics, including servers, clients, transmission media, data, printers, among a great variety of hardware resources. and software.
In order to set up a computer network, it is then necessary to have a series of components , and the truth is that the larger a network is, the more elements it will need to function efficiently.
For example, if we need to set up a home internet computer network, we will need to cover the entire spectrum the use of certain elements such as Wi-Fi signal repeaters and amplifiers.
Now, let’s see roughly what are the essential components that a computer network should have.
Components of a network: Servers
These are computers on which shared files, programs, and the network operating system are stored. Through the servers, all users that are part of the network can have access to these resources. It should be noted that there are different types of servers, which can also have a series of specific functions, such as print servers.
Components of a network: Clients
These are precisely the computers that access the computer network and make use of the resources that are shared in it through the servers. As an example we can mention that each of us are clients every time we connect to the internet.
Components of a network: Transmission media
Also known as channels, links or lines, transmission media are the facilities that are used to interconnect computers within a computer network , the most common being twisted pair wire, coaxial cable, and fiber optic cable.
Components of a network: Shared data
As the name implies, shared data is data that file servers provide to clients, including for example data files, programs for accessing devices such as the printer or email, and so on.
Components of a network: Network interface card
To be able to connect to the computer network, each of the computers must have a network interface card, through which the data is sent and received, and at the same time the flow of data between the PC and the the network .
Components of a network: Local operating system
The local operating system is what allows our computers to access the files found on the servers and perform different tasks , such as being able to print a document through a shared local printer.
Components of a network: Network operating system
It is a program that runs on servers, and that allows computers to communicate with servers through the computer network.
Components of a network: Router
This device makes the connection between the internet and a LAN network possible. Through the router, computers can have access to the network, such as the Internet . There are currently two types of router, the one that uses cables and the wireless.
Components of a network: Switch
Basically it is a telecommunication device that comes to be like a hub, and in this way collaborate in the connection between computers and routers. In general, the switch connects the source with the destination directly, which allows increasing the speed of the computer network. In any case, it should be noted that it is not always necessary to use a switch and a router at the same time, especially if it is a small network for the home or office.
Other elements that can be part of a computer network are the so-called Hubs, which are devices that divide a network connection between multiple computers, such as if it were a distribution center, and at the same time a network can be composed of shared peripherals, as is the case with printers, scanners and others.
How computers communicate
The efficiency of a data communication system depends fundamentally on:
1. Delivery: The system must deliver the data to the recipient. The data should be received only by the target device or user.
2. Trust: The system must guarantee the delivery of the data . Modified or corrupted data in a transmission is of little use.
3. Delay time: The system must deliver the data in a finite and predetermined time. Data delivered late is of little use . For example, in the case of multimedia transmissions, such as video, the delays are very annoying, therefore, the data must be delivered practically at the same moment in which it is generated, that is, without significant delay.
A basic data communication system is made up of five elements
1. Message: It is the information to be transmitted. It can be made up of text, numbers, images, audio and video, or any combination of these.
2. Transmitter: It is the device that sends the data message. It can be a computer, workstation, phone, video camera, or any other device.
3. Receiver: It is the device that receives the message.
4. Medium: It is the physical path through which a message originated and directed to the receiver travels.
5. Protocol: It is a set of rules that governs data communication. Represents an agreement between the communicating devices.
Direction of data flow
A communication between two devices can occur in three different ways: Simplex, Half-Duplex or Full-Duplex.
Simplex: In simplex mode, communication is one-way, as in a one-way street. Only one of the two devices on the link is capable of transmitting; therefore, the other will only be able to receive.
Half-Duplex: In this mode, each device can transmit and receive, but never at the same time. When one device is transmitting the other is receiving and vice versa. In a half-duplex transmission, the full capacity of the channel is given to the device that is transmitting at the moment.
Full-Duplex: In this mode, both devices can transmit and receive simultaneously . Signals in opposite directions share the capacity of the link or channel.
Point-to-point: Provides a dedicated link between devices.
Multi-point: It is one in which more than two devices share a single link.