The advantages of wireless networks are well known: rapid deployment and scaling, mobility for users, easy connection of new devices. Moreover, many modern gadgets such as smartphones, tablets and smart glasses, you can connect to the network at a good speed only via Wi-Fi (EDGE, 3G is not included). It is not a secret and disadvantages of wireless transportation: weak protection signal transmission compared to cable networks, lower speed, high vulnerability to various sources of interference and attackers. How to remove such disadvantages and achieve the same reliable performance of Wi-Fi as well as cable networks? Experts of specialized network integrator NETWAVE share their experiences and practical advices.
Features of wireless transportation
While deploying Wi-Fi specialists have to solve two major problems: how to ensure an acceptable rate and how to ensure reliable data protection. Their decision is fundamentally different from the challenges faced by system integrators in the projects of construction of traditional wired networks. The fact that in the second case is clearly defined volume: the network is calculated for the number of users equal to the number of ports in the switch.
There is no such limitation in the WI-FI network: the number of connections can be varied over a wide range. In this case, the airwaves, in which data is transmitted, is the same for all. Working in it, customers are waiting their turn for transfer data, and the more their number – the lower the rate of information transfer. In this way, main problems are connected with reduction of speed of information transmission and interruptions of service at all, especially if the network is connected directly a large number of client devices. Moreover, in the airwave can operate a variety of equipment which may be interfering with the service: other Wi-Fi access point, transmitters Bluetooth; also microwave ovens, electric welding apparatus generate broadband radio noise, radio propagation also prevent large metal objects, metal screens, shelves in warehouses etc.
If the noise and screens are absent, Wi-Fi signal can extend beyond the object where the wireless network works. This allows attackers to listen to Wi-Fi network, so the usage of reliable mechanisms for protect Wi-Fi network is very important.
Two types of Wi-Fi-networks
Although the principle of the network based on Wi-Fi technology is the same for any of the equipment, in general, these networks can be divided into two types: simple consumer and professional corporate. The difference between them consists in the features of architecture, authentication, roaming, and of course, in the level of security and reliability.
“In our work, we are facing with a lot of attempts to bring these two types of networks to a common denominator. That is, consumer networks that built on inexpensive equipment, to pass off as a professional Wi-Fi. You have to understand why some of the access points cost only 500 UAH, and others – 1,000 USD. The difference is due to opportunities offered by both types of devices and solutions based on them,”- says Andrey Rotach, Business Development Director of NETWAVE.
In addition to high productivity and security, corporate Wi-Fi-equipment offers additional features for the system administrator. We are talking about centralized control, which allows you to control network, to monitor hacking attempts, network intrusion, problem areas, etc. In addition, the professional network reacts on the appearance of interference and in the case of their significant impact rebuilt on the other radio channels and continues to function.
Reliable protection and roaming
In corporate wireless networks are used a slightly different approach to information security than in the consumer. If the usual Wi-Fi-network uses the public key, which all the neighbors or sometimes, malefactors know after a while, the corporate network individual authentication is used for each user, and he can connect with his own key. Also, for security purposes, client devices forbid to connect to third-party Wi-Fi-networks, even if the signal of corporate access point is too weak, and the public network has the same name and more powerful signal. As noted by Victor Penkovsky, NETWAVE engineer, and for this we use additional applications that require from the owner of the phone to confirm that the client moves to another network.
Consumer Wi-Fi-equipment allows us to build a network, which may consist from only a few access points, and peripheral points will be radio extenders of the main point. In professional networks may work hundreds of access points. When the user moves from the coverage of one point to another point smooth, “seamless” roaming is providing.
Stages of Wi-Fi-network building
The process of building a corporate Wi-Fi-network including the following steps:
- formation of requirements and development of technical specifications;
- radio prospecting of existing or radio planning of the new wireless network;
- modernization or implementation of new solution;
- final testing and commissioning.
The first step is to form a technical task. Here it is necessary to determine the functional purpose of the network, analyze current situation its growth potential, and calculate possible peak loads, also take into consideration particular qualities of environment in which the network will be launched. This is an important step, from the results of which will depend the successes of implementation of solution.
The second step is performed by a set of actions by determining of types, characteristics and location of access points for providing of required wireless coverage and signal level. For this we need to provide modeling of radio environment with the help of special programs and further verification of calculations using actual measurements at the object. When performing measurements it is important for object to be on the final stage of building readiness and received results maximum displayed the resulting wireless coverage after the introduction of the network.
Generally radio planning is one of the most responsible phases of the project, commented Andrei Rotach. It consists of the following steps:
- research of premises plan with indicated locations where measurements are needed and with possible locations of the access points.
- location of access points in assuming places and scanning of airwaves to determine the characteristics of the wireless network.
- prepare report of providing work results which includes coverage map, the level of interference, noise and presence of external interference in the airwaves.
Next step is deployment of the network with the installation and setting of equipment. After is recommended to repeat of radio prospecting for confirmation of required result.
Also radio prospecting is needed in the case of modernization of the existing wireless network to determine the properties of the network, such as level of signal, interference, ratio of signal/noise, the presence of third-party wireless networks. These data are used as a basis for further calculations.
As Viktor Penkovsky said, Wi-FI network is easy to scale by adding more access points, or replacement of existing points to more productive, but this is possible only if originally proper network design with the possibility of growth was made.
“Pitfalls» of Wi-Fi
Experts point out that while construction of wireless network it is important to understand the tasks in the right way, which will be assigned on the network and to perform appropriate design. A common mistake is wrong estimation of the maximum probable number of users. Especially often it happens while design of networks in the hotels, airports and other public places. As a result, at the time of peak loads the network may be completely unusable.
Furthermore, when constructing an internal corporate Wi-Fi-network it is necessary to use not such approach to security, as in the case with public networks. In the second case not necessarily encrypt traffic, which is generated by users, because by saving on encryption greater bandwidth can be provided. Encryption is obligatory in the case of an internal corporate network.
Another common mistake: the absence of wireless network monitoring that does not allow determining how “clean” at the moment is ether. “It may be that in the current time Wi-Fi works fine, and a minute later in neighboring room was turned on its own access point (or the source of interference) and the network immediately began to work worse. Also need to perform qualitative radio planning to determine the properties of the covering, because there are areas where the signal falls very strongly, although theoretical calculations talk about reverse. It happens due to the detection, for example shielded premises, about which the customer initially says nothing, “- says Andrei Rotach.
In some cases, the problem of network capacity solves transition in the 5 GHz range, which is less busy. This range differs from the standard 2.4 GHz reduction radius of transmission, at the same time, there can be used more radio channels.
If during the project one of the stages will be missed, it is fraught with instability of the network, appearing of the “white” spots in the covering and low productivity, emphasizes Victor Penkovsky. At the same time, responsible and professional approach for building a wireless network will help to create new or optimize existing Wi-Fi for its working on “full” – according to the tasks entrusted to its expectations.
NETWAVE experts state and prove in practice the reality of building reliable wireless corporate networks which operate as effectively as wired. Proper planning, forecasting of a possible maximum number of connections, the analysis of airwaves and high-quality installation – these are the key factors that help to create a working Wi-Fi.