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Adoption of wireless Internet access will give us what kind of benefits?

1. Business people
Wireless networks with mobility, there is no laptop battery cable restrictions, can be moved in different places of work, real-time access to information;
2. Families are
A wireless network without wiring through walls or over the ceiling to eliminate the tedious work of wiring, home beautiful, building networks quickly, at the same time saving wiring costs.

In the formation of a wireless network, we will often see these types of agreements:

1.IEEE 802.11a: use the 5GHz band, the transmission speed of 54Mbps, is not compatible with 802.11b;
2.IEEE 802.11b: use the 2.4GHz band, the transmission speed of 11Mbps;
3.IEEE 802.11g: use the 2.4GHz frequency band, the transmission speed of 54Mbps, can be backward compatible with 802.11b;
4.IEEE 802.11n (Draft 2.0): for the new Intel Centrino 2 notebooks and high-end routing, it can be backward compatible, the pavilion dv6000(hp dv6000 battery) laptop battery transmission speed of 300Mbps.

Standard operating frequency of theoretical maximum transmission speed from the main application of
802.11b 2.4GHz 11Mbps 100 Mi video, voice, image
802.11a 5GHz 54Mbps 100 Mi hospitals, mines and other special occasions
802.11g 2.4GHz 54Mbps 100 Mi LAN access, video, voice, image
802.11n 2.4GHz 108-600Mbps 200 Mi high-definition video, LAN access, video, voice, image

Buy recommendations:
For notebook with a wireless network module, the current commercially available are mainly 802.11a/b/g wireless card, only a small number of laptops with Centrino 4 802.11a/g/n wireless card, for the Internet is a play 3D online games, QQ video friends, the current mainstream 802.11g fully meet demand, but this kind of routers are usually of lower prices, more in between 200-300 yuan; while playing for the need for wireless high-definition video friends, or choose to 802.11n ideal, but should be noted that, 802.11n routers in 342661-001 laptop battery a thousand dollars more than current prices, not cheap.

A, 802.11b Wi-Fi standard

In June 1997, the world's first wireless LAN standard IEEE802.11 worked out, opened a prelude to the development of wireless LAN, wireless Internet access is possible. In 1999, the beginning is the introduction of 802.11b, it works in the 2.4GHz band, maximum transmission rate of 11Mb / s, the actual work rate of around 5Mbps. 802.11b supports the outdoor range is 300 meters, in the office environment for up to 100 meters. With the normal wired LAN 10Base-T standard is almost at the same level. As the facilities within the company, of course, you can basically meet the use requirements. IEEE 802.11b uses are open 2.4GB band, does not require the application can use, this band is also wireless and home appliances most frequently used frequency bands, such as cordless phones, Bluetooth, microwave ovens are using this band, it will inevitably be disruptive. And if you focus on power, then it may disappoint you, because lower data rates and longer than 802.11b header will result in 802.11a / g networks, 345027-001 laptop battery power consumption is much higher.

In practice, 5Mbps Internet access and entertainment to meet the simple requirements to the common rmvb format is now online, for example, its rate is usually 600-800kbps, but common to Divx / Xvid encoded avi video file, its rate is still around 1000-2000kbps, at the rate of decay is not serious cases, 802.11b can satisfy. As for the QQ, the Internet, online video is even more goes without saying. However, for local area networks for the exchange of data, 5Mbps rate is really shabby a point.

Benefits: basically meet the requirements of wireless Internet access
Disadvantages: speed is not high, 802.11b network power consumption and high

802.11b exposed many shortcomings, in PP2182L laptop battery particular, is too slow, so that people have to step up the development of the new agreement, as the 802.11b successor, 802.11a and 802.11g have cause for concern. First, they were approved by the IEEE (Institute of Electrical and Electronics Engineers) approved the wireless LAN standard, the standard means that manufacturers establish their recognition and support; Secondly, they have up to 54Mbps transmission speeds, making large-capacity data transmission possible, a great solution to the bottleneck of the 802.11b; Finally, on security, 802.11a and 802.11g also superior compared with 802.11b. But a close friend were in the market will find that 802.11g products on the market are many, but have the same speed of 802.11a products are not common, why? Let's analyze under the 802.11a standard.

2, 802.11a wireless Internet standard

802.11a standard, which work in the 5GHz band, the connection speed of up to 54Mbps. In the interference context, it should be better 338794-001 laptop battery than the 802.11b standard, it is because 802.11a work loose under the 5GHz band, with 12 non-overlapping channels, providing more available channels, can effectively reduce the channel between the "conflict ", and the use of 802.11b frequency and variety of household appliances and medical equipment, frequency of use is shared. "Cheng also Xiao, Xiao He also lost", in the high anti-interference ability of the 5GHz band, making 802.11a transmission distance greatly reduced, indoor transmission distance is only 30 meters or so, because the 5GHz band of electromagnetic waves in the event of wall, floor , furniture and other obstacles when the reflection and diffraction effects are not as good as a good 2.4GHz frequency band of electromagnetic waves, resulting in smaller defects 802.11a coverage; Secondly, as design complexity, based on the 802.11a standard 802.11b wireless products than the cost of higher and more certainly than this since the price of 802.11b products, prices must be high, and also not compatible with 802.11b. 802.11a and 802.11g is not dominant in comparison, is not 802.11a will withdraw the market? The answer is no! Take the hospital for, 2.4GHz band is a lot of medical equipment used by the band, such as: cardiac pacemakers, 802.11b uses 2.4GHz frequency band is also bound to these devices would interfere with, the consequences are PP2182D laptop battery unimaginable, so 802.11a uses a unique frequency band, as well as its excellent anti-jamming capability in the mines, hospitals, scientific research fields, or place.

In practice, although 802.11a wireless cards abound, such as the Intel 3945ABG, you can also supports 802.11a/b/g, support for 802.11a, but the routing is quite scarce and prices high above, so now in addition there are several units have special requirements, such agreements rarely used.

Advantages: available channels is an advantage of its strong anti-interference and multi-channel design to make 802.11b / g far behind.
Disadvantages: Some countries regulate the 5GHz band, general civil meaningful

3, 802.11g Wi-Fi standard

802.11a products fast, but the high frequency band, transmission distance is not ideal; and 802.11b products work in the penetrating ability of the 2.4GHz band, the regret that is mainly the speed. In 2000, avoid weaknesses of the 802.11g standard have emerged, which still is used 2.4GHz frequency, which can be backward compatible with conventional Pavilion ZD7000 laptop battery 802.11b standard, also maintained a distance of 100 meters effective range, but the speeds are significantly improved, reaching 54Mbps.

We have already mentioned above, 802.11b is adequate for the vast majority of basic network use, but the speed of the LAN visits are less favorable. 802.11g is good up to this point, 54Mbps rate Although they are not wired networks, but basically has been able to meet the vast majority of users. 802.11g is currently the most mainstream wireless protocol, the vast majority of users are using this wireless protocol.

Benefits: Network of quality and high bit-rate is compatible with 802.11b products
Disadvantages: 54M speed can not meet the higher requirements.

Super G

The introduction of 802.11g standard, or to make a number of Internet users to enjoy a pleasure, but the pace of the development of wireless networks did not stand still, to the brand, led by Netgear wireless device manufacturers subsequently introduced a model called the Super G wireless network products, through the dual-channel integration, its transfer rate of up to amazing 108Mbps, but this agreement does not through the IEEE organization for accreditation, which is limited to part of the vendor's products, only the simultaneous use of the vendor's routing and wireless card, we can to achieve a rate of 108Mbps, does not satisfy any one condition only has 54Mbp / s of the standard CGR-B1870AE laptop battery rate.

4, 802.11n Wi-Fi standard

With the rapid development of mobile communications services, high-performance WLAN market demand are increasing. In order to meet this demand, in 2003, IEEE started to develop 802.11n standard. Currently this standard has not yet been finalized, but the wait at all vendors have launched all kinds of products, as each speaker technologies, 802.11n products from different vendors and thus can not be fully compatible, although its first-class performance, or so many users could not wait to go to early adopters.

Let's take a look at 802.11n standard features, the emerging 802.11n standard with up to 600 Mbps rate is the next generation of wireless network technology. First of all, 802.11n standard is still in the 2.4 GHz, guaranteed with the compatibility of 802.11b and 802.11g standards, the rate was significantly upgraded to 108Mbps-600Mbps. Secondly, 802.11n supports F4486A laptop battery this year's just-completed 802.11e QoS standards, safety, reliability has been strengthened; Finally, in the distance in the wireless, 802.11n can have 200 meters of wireless distance than 802.11b and 802.11g have raised a step.

Currently, 802.11n has not yet formally a large-scale popularization of solutions from different vendors are not compatible with each other, to their popularity is a big problem. However, the actual rate of 108Mbps-300Mbps, or enticingly endless. First, the rate of the LAN to access the bottleneck has been completely ceased to exist, and for the growing popularity of high-definition video, such as the H.264/VC-1 coding, the actual rate more in 20Mbps-40Mbps, while the multi-track such circumstances , bit rate will be further improved, so much traffic has been completely incompetent 802.11g, 802.11n can only well positioned to meet and therefore ready to build for the users of home wireless high-definition networks, 802.11n can be said that the election must be.

Benefits: to meet the high-quality voice, video, streaming media needs a wider transmission range
Disadvantages: IEEE has not yet finally been adopted by the F4486B laptop battery Organization and corresponding high prices of wireless products