Today various wireless standards fall under the 802.11 parent standard. These include 802.11a, 802.11b, 802.11g and a number of other standards. Below describes each standard.
WIMAX is basically mobile broadband and is similar to 3g but faster and covers a wider range of area. WIMAX is in fact a 4th generation technology, and is powerful like the broadband we have at home providing an average of 3Mb and up to 75Mb of connectivity. So it is wireless broadband that covers a huge area, not just your home but anywhere in the city.
It is considered a reliable high speed connection, giving you the ability to do all the things you want to do, which you can’t really do on a 3g network. Mobile WIMAX is installed in cars as well providing GPS and other features. WIMAX is actually seen as an alternative to Cable and ADSL as it was designed to deliver last mile connectivity to broadband users.
WIMAX is like a WAN technology, or more like a MAN, but a wireless MAN. Using a WIMAX tower, a service provider can give access for miles to homes and businesses. WIMAX is now popular in the US and available from major wireless service providers. It won’t be long before WIMX is implemented worldwide. CPU manufacturers Intel are supporting the WIMAX technology by providing laptops and mobile devices that support WIMAX connectivity. WIMAX provides broadband and wireless access up to 25 – 30 miles, now that is quite impressive!
This standard provides higher data rates, more throughput and a longer range than the previous standards, 802.11a/b/g. 802.11n works in the 2.4Ghz frequency, and data rates can exceed 300Mbps. Now comparing this to 802.11a/b/g, this standard is far more powerful. This standard supports the MIMO (Multiple In, Multiple Out) technology, which is the engine behind the powerful standard. Basically the routers supporting 80.211n makes use of more antennas, which listen for multiple signals at the same time.
The signal also travels further than that of the 802.11g standard. Although 802.11n is backwards compatible with g and b, it will not be using the full force of 802.11n. To make use of the speed of the wireless n standard, both laptop and router must support this standard.
802.11b was improved upon, and resulted in the 802.11g. This is the more common standard in use now, which works in the 2.4Ghz band and provides up to 54Mbps download bandwidth speed. 802.11g will work up to the range of 300 feet. This standard is also backward compatible with 802.11b.
802.11e and 802.11f
802.11e provides the ability to do QOS. QOS provides prioritisation of traffic. 802.11f allows a user to roam from one access point to another and provides the ability for access points to communicate this information.
This standard works in the 2.4Ghz band, and provides a download speed of up to 11Mbps. 802.11b also supports a range of up to 300 feet. 802.11b is compatible with 802.11g and is still in use today.
This standard works in the 5Ghz frequency band. Because the 802.11b and 802.11g standards work in the 2.4Ghz band, they are not compatible with the 802.11a standard. However many vendors have implemented both the support for 5Ghz band (802.11a) as well as the 2.4Ghz band (802.11b and 802.11b) giving the use of both options to pick from. The good thing working in the 5Ghz is, it is less crowded when compared to the 2.4Ghz frequency. Other devices already use the 2.4Ghz frequency, such as baby monitors and microwaves. This is why when we turn on the microwave, this can affect the wireless network and is noticed when browsing or playing games online. 802.11a provides up to 54Mbps of download speed. However the range on the 802.11a is far shorter than that of the standards that work in the 2.4Ghz band such as the b/g standards, and to get the most out of the 802.11a standard in terms of bandwidth, then it has to be fairly close to the laptop or access point. The maximum range is up to 60 feet. 802.11a is more common in the United States, and is hardly used in the UK or most of the European countries.
802.11i and 802.1x
802.11i provides more security and capabilities for wireless networks such as authentication, including mutual authentication as well as better encryption unlike WEP.
Extensible Authentication Protocol (EAP) and 802.1x have been introduced to provide the above capabilities, and are part of the 802.11i standard. Within the 802.11i standard, other strategies such as the use of integrity to detect modification and Temporal Key Integrity Protocol to provide more randomness to the values which proved useful to the already flawed WEP were introduced. TKIP was a temporary fix for WEP users since they did not have to replace any hardware to integrate TKIP with WEP. The 802.11i standard also introduced the new AES encryption technology.
802.1x is a port based access control framework which ensures users can not log into the network without authenticating first. In the 802.1x a user would authenticate via the router or access point to a Radius or TACACS server. Authentication protocols such as EAP-TLS which authenticates with the use of digital certificates are used to provide credentials, as well as other higher layer EAP protocols which can be used. The 802.1x is also a part of the 802.11i standard, and as you can see 802.11i provides a number important security add-ons to the already vulnerable 802.11 standard. Now authentication, mutual authentication and better encryption can be used with the use of 802.11i, which you either could not do or were not done very well previously.
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