One of the most crucial advantage that wireless network has over wired counterpart is that Wi-Fi allows LANs to be deployed without cabling for client devices, typically reducing the costs of network deployment and expansion. Spaces where cables cannot be run, such as outdoor areas and historical buildings, can host wireless LANs or set up a wifi spot.
As of 2007 wireless network adapters are built already into most modern laptops. The price of chipsets for Wi-Fi continues to drop, making it an economical networking option included in ever more devices. Wi-Fi has become widespread in corporate infrastructures, which also helps with the deployment of RFID technology that can piggyback on Wi-Fi account.
Different competitive brands of access points and client network interfaces are inter-operable at a basic level of service to make it ever so easy for wifi dummies to to connect utilize with little or no tech assistance . Products designated as "Wi-Fi Certified" by the Wi-Fi Alliance are backwards inter-operable.
Wi-Fi is a global set of standards. Unlike mobile telephones, any standard Wi-Fi device will work anywhere in the world. Wi-Fi is widely available in more than 250,000 public hotspots and tens of millions of homes, corporate settings and university campuses worldwide. WPA is not easily cracked if strong passwords are used and WPA2 encryption has no known weaknesses. New protocols for Quality of Service (WMM) make Wi-Fi more suitable for latency-sensitive applications (such as voice and video), and power saving mechanisms (WMM Power Save) improve battery operation.
Disadvantages of Wi-Fi
It is difficult to find any technology without limitations. This article is pertinent that all wifi users must take note of especially for anyone that is still nursing the thought that it is meant for wifi dummies. Spectrum assignments and operational limitations are not consistent worldwide. Most of Europe allows for an additional 2 channels beyond those permitted in the U.S for the 2.4 GHz band. (1-13 vs. 1-11); Japan has one more on top of that (1-14). Europe, as of 2007, is now essentially homogeneous in this respect.
A very confusing aspect is the fact a WiFI signal actually occupies five channels in the 2.4 GHz resulting in only 3 non-overlapped channels in the US: 1, 6, 11, and four in Europe: 1,5,9,13
Some countries, such as Italy, formerly required a 'general authorization' for any Wi-Fi used outside an operator's own premises, or require something akin to an operator registration. Equivalent isotropically radiated power (EIRP) in the EU is limited to 20 dBm (0.1 W).
Power consumption is fairly high compared to some other low-bandwidth standards, such as Zigbee and Bluetooth, making battery life a concern. The most common wireless encryption standard, Wired Equivalent Privacy or WEP, has been shown to be easily breakable even when correctly configured. Wi-Fi Protected Access (WPA and WPA2), which began shipping in 2003, aims to solve this problem and is now available on most products. Wi-Fi Access Points typically default to an open (encryption-free) mode.
Novice users benefit from a zero-configuration device that works out of the box, but this default is without security enabled, providing open wireless access to their LAN. These configuration should not be seen as a lee way to bypass all the so called problem of connecting to wifi usually experienced by new users. To turn security on requires the user to configure the device, usually via a software graphical user interface (GUI).
Wi-Fi networks that are open (unencrypted) can be monitored and used to read and copy data (including personal information) transmitted over the network, unless another security method is used to secure the data, such as a VPN or a secure web page. ("Wifi for Dummies: HTTPS/Secure Socket Layer.) Many 2.4 GHz 802.11b and 802.11g Access points default to the same channel on initial startup, contributing to congestion on certain wireless channels.
To change the channel of operation for an access point requires the user to configure the device.
Wi-Fi networks have limited range. A typical Wi-Fi home router using 802.11b or 802.11g with a stock antenna might have a range of 32 m (120 ft) indoors and 95 m (300 ft) outdoors. Range also varies with frequency band. Wi-Fi in the 2.4 GHz frequency block has slightly better range than Wi-Fi in the 5 GHz frequency block. Outdoor range with improved (directional) antennas can be several kilometers(kilometres) or more with line-of-sight.
Wi-Fi performance also decreases exponentially as the range increases. Wi-Fi is also less reliable and fast as Ethernet or other cable systems, 802.11g networks have a maximum of 54 Mbit/s whilst cables can reach speeds of 1000 Mbit/s or more. wifi is not suitable for servers or users who need fast internet access, for example, online gamers.
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