Often when organizing home or small office networks, devices called routers are used to combine computer and mobile devices with each other or to access the Internet. Unfortunately, many users very often confuse the concept of a router and a router, although in a general sense both of these terms are equivalent. But the latter are a single type of network equipment. And the class of routers includes other devices, for example, the same DSL / ADSL modems, repeaters, signal amplifiers, etc. Next, we propose to consider the purpose and principle of the router, as well as get acquainted with some basic concepts that are useful when performing correct settings. But first, let's dwell on what such a device is.
What is a router?
If we talk about the device itself, the English term Router, from which the Russified name came from, translates precisely as a “router”. And with this, at the time, a lot of incidents arose, since in the same stores you could see separate racks for both routers and routers. Then the term in question was firmly established. All routers began to be called routers and vice versa (although this is in a sense wrong).
But back to the described devices. Today, devices designed for wireless signal distribution based on Wi-Fi technology are most widely used. However, they themselves may not be wireless in their pure form. This applies only to those cases when several routers are used to organize access to the Internet or to obtain the possibility of connecting more computers and mobile devices to the same network, one of which is the main one, and the rest play the role of repeaters, that is, they work in the AP access point mode .
It is necessary to connect the provider's cable to the router itself. Only then can he give out a signal. In this case, each device connected to the router wirelessly is automatically assigned an address in the subnet.
It is not in vain that when creating a Wi-Fi connection, it is recommended to use the automatic receipt of all parameters in the IPv4 protocol settings.
In this regard, the principle of operation of a Wi-Fi router in general boils down to the fact that it broadcasts a signal in a certain radio frequency range, and the distributed signal is received by all devices that are within the range of the router. In this regard, we can immediately draw conclusions about some of the shortcomings of such network equipment, which mainly consists only in limiting the distance over which a wireless signal can be transmitted (on simple models, it averages 100 meters in direct line of sight, and sometimes the distance can be significantly reduced due to the presence of various obstacles that impede the passage of radio waves).
In addition, if you pay attention to home devices, almost all inexpensive models of routers have restrictions on the number of simultaneously connected computers or mobile devices. In offices, it is customary to use more powerful models, although the method of creating additional access points looks less costly.
Finally, routers can vary quite a lot in both performance (1-, 2- and 3-antenna) and data transfer rates (from 0.1 Mbit / s to several Gbit / s).
Types and classification
With the principle of the WiFi router in general, so far everything is clear. Now let's dwell on the classification of this type of device. In general, in a global sense, all routers can be divided according to the type of access to external and local networks.
The first category includes ADSL, Ethernet, and LTE routers. According to the second criterion, the devices are divided according to the principle of operation of routers in terms of broadcasting the distributed signal (wire and wireless). In the first case, the organization of network connections is based on the use of wires. For the second, the same radio signal is used, which was mentioned above.
Separately, it should be noted and classification according to the criterion of equipment design. Distinguish between standard and combined devices. The second type is more interesting in the sense that some models are equipped with additional USB ports, which makes it easy to connect to them, for example, 3G modems, which add their own communication channel when the signal from the main provider is lost.
Also, external hard drives are often connected via the USB interface, which is used when creating your own FTP servers. Some models already in the factory assembly are equipped with built-in 3G / 4G modems, although it is the modem function that any router has. The only difference is that it serves only one device. A router works with several at once (though ADSL modems can be configured to work in router mode).
In a separate category, it is worth highlighting routers to which you can connect external firewalls (firewalls in the form of "iron" equipment), and in some models they can be internal (either "iron" or software). Finally, even printers that support direct printing can be connected to some types of routers, which allows them to be used for simultaneous access from multiple devices over the network.
The principle of the Wi-Fi router: what to look for when choosing a device?
Let's move on to the main criteria that should be considered when buying a device. First and foremost, supported network access protocols. Agree, if the router cannot work with the protocol that the provider originally intends to use to connect, you can not even think about any access to the Internet.
The second point, if you choose a wireless router, is associated with support for Wi-Fi standards (IEEE802.11).
Since they are developing rapidly, it is better to give preference to that device in which there is support for absolutely all standards, among which the main ones are b, g and n. But one of the most recent developments can be called a combined ace standard, which in its characteristics exceeds all others by several times.
Finally, pay attention to the limit on simultaneously connected devices. Although this is not the most basic indicator, since even at home you can make an additional access point from a regular laptop or mobile phone, which will allow you to connect more devices and increase the range of the signal from the main repeater when the devices are far away from each other. For example, in a private house with a large area or number of storeys.
Network access protocols
Now a few words about the principle of the router as applied to the main network access protocols. Today, the main standards are PPTP, PPPoE and L2TP (but there are others). Most of them are used in organizing secure VPN connections and private virtual networks, and it is believed that PPPT is the most secure. But the same standard PPPoE allows you to transfer data much faster. In general, before purchasing equipment, it is better to check with your provider right away for which standards you need support for.
The device and the principle of operation of the router in relation to the firmware
Often these devices are called peculiar mini-computers with their own software. Yes, indeed, it is. The device itself has its own processor and some kind of operating system, usually called firmware. But to understand how this all works, you need to consider the principle of the router (router) in relation to the organization of the so-called routing tables, which are responsible for the distribution of the signal.
There are two types of these types: dynamic and static routing. In the first case, a certain number of updated addresses are stored in the router’s memory, and the device itself sends test signals to connected devices at certain intervals to check their status.
In the second case, the organization looks more complex, since the routing table contains only clearly defined static (unchangeable) addresses, and if an unknown address is found that is not in the main list, it is ignored (blocked). As already understood, using this principle of the router provides maximum protection against possible interception of transmitted data packets by intruders. But the setup is quite complicated and time-consuming.
Device connection
Finally, we figured out the basic principles of the Wi-Fi router for a home or office. It's time to move on to the practical application of knowledge. The first step is to connect and configure the router. There is nothing complicated here.
Turn on the router using the power adapter in the mains. Then connect the provider's cable to the WAN (or Internet) port, which is usually colored blue (sometimes yellow). Connect the supplied cable to one of the LAN connectors and plug the other end into the corresponding RJ-45 connector on the network card of your computer or laptop (this is necessary for the initial setup).
How to enter the web interface of the router?
Now you need to go into the settings. The principle of operation of routers is such that to log in you only need to use some kind of web browser installed on your computer (yes even Internet Explorer).
In the address bar for most known models, enter the address 192.168.0.1 or ending with 1.1 (which, by the way, is the address of the main gateway), and in the authorization fields that appear, enter admin twice. In general, you can find out the address, username and password on a special label on the back of the device, as some manufacturers of such equipment can use other combinations.
Basic parameters and settings
So, you entered the interface. Of course, you can immediately use the "Wizard" of simple settings. It is enough to enter the options provided by the provider when concluding the service contract, without forgetting to specify the network name, access password and address type (dynamic or static). Usually, after making the initial settings, everything should already work.
If, for some reason, there is no signal distribution, look at the parameters in the wireless section for additional details, where the points of enabling wireless broadcasting of the router and broadcasting of SSID must be activated.
For some programs installed on a computer, port forwarding is often required, and not even in the Windows firewall, but on a router. The principle of operation is somewhat reminiscent of all the steps to create a new rule in the firewall, but it looks simpler. Nevertheless, the parameters are set in the forwarding section, where there is a Port Forwarding (or Port Triggering) subsection.
Firmware update and some communication problems
It is hoped that clarity is introduced into the principles of the router. It remains to add a few words about the correction of possible violations in the operation of the device or in case of loss of communication.
Most often, it is enough to perform a parameter reset by disconnecting the router from the mains for about 15-20 seconds, and not rebooting the device by pressing a button on the back. If this does not help, try resetting the network settings on the computer using the command line and ipconfig applet tool for this . Also, a full reset to the factory state can be performed on the router itself (there is a special section in the web interface for this). In extreme cases, in the system tools section, you can install the updated firmware, if available.