Although approximately 13 standards for wireless connectivity exist, fortunately, you don't need to become familiar with each and every standard. As you delve deeper into the wireless world, the standards referenced most often are 802.11a, 802.11b and 802.11g. Another standard that you'll run across — yet to be ratified but lurking on the horizon — is 802.11n. These four standards define the protocols and specifications used to transfer data via radio signals — so they're the only ones for which you need a good working knowledge. Here's the short course:
- By getting a basic handle on standards, you can make better choices when you're buying wireless gear.
- The 802.11a standard specifies operation in the 5.0GHz band.
- The 802.11b, g, and n standards specify operation in the 2.4GHz frequency band.
- Because 802.11a operates at a higher frequency, it has a shorter range and it's more likely to be adversely affected by obstructions. Consequently, this standard has found its niche in the wall-free world of corporate cubicles.
So which of these standards can do the job for you? Well, here's a brief rundown of the major attributes of the standards you'll encounter most often:
802.11a: Connecting over short distances
The 802.11a standard covers the 5GHz band; devices that comply with it are incompatible with the 2.4GHz-band b, g, and n standards. 802.11a is most commonly found in businesses that require a high-speed wireless network connection to transfer files between desktop or laptop computers. If your primary goal is connecting to the Internet at hotspots — without getting all business-obsessed about it — you can safely ignore this standard.
802.11b: Opting for the basic standard
802.11b is the standard that started the boom — and it's best-suited for connecting to the Internet or for streaming audio or video.
- The theoretical maximum bandwidth (in effect, how fast data can be transferred or transmitted) is 11 Mbps.
- This is the standard hotspots currently use most often.
- Both the 802.11g and 802.11n standards are, or will be, backward-compatible with this standard.
- Backward compatibility — a requirement of the 802.11 standard — means that any new versions must be designed to work and play well with older versions.
802.11g: The speedier standard
Ratified in 2003, this standard is quickly becoming the favorite for folks setting up home networks (and yes, an RV counts as "home" — but you knew that).
- The theoretical maximum bandwidth is 54 Mbps.
- It's most commonly found in home or business networks as well as newly established hotspots. Some owners of established hotspots are upgrading aging 802.11b equipment with new equipment that conforms to 802.11g as well.
- It's backward-compatible with the 802.11b standard.
- 802.11g is, maybe, more than a home user needs, but it's still well-suited for connecting to the Internet for basic information. It also gets high marks for streaming audio and video, head-to-head gaming, and transferring large files between computers on the same network.
- You can also go for 802.11g "enhanced." This is sometimes called pre-n, enhanced g, and by proprietary names such as SpeedBooster, Super G, Xtreme G, and so on. It isn't a standard in its own right; rather, it's a variation of the 802.11g standard.
• Theoretical maximum advertised speeds up to 108 Mbps.
• Most often found in home networks.
• Generally compatible with the 802.11b and g standards, although it's not ideal for use in mixed-standard environments (the enhanced abilities are usually lost).
• If a hotspot uses, say, an access point conforming to 802.11g, but client computers that conform to 802.11b, g, or even "enhanced g" can still connect to it, it's a mixed-standard environment.
• It's best-suited for use in integrated "enhanced-g" networks. It's overkill for a basic Internet connection, but it shines at handling streaming audio and video, gaming, and huge file transfers.
Connecting 802.11b and g devices in the same network won't adversely affect the speed of b-standard devices, but it will slow down the general performance of the g-standard devices.
The difference in price between 802.11b- and 802.11g-standard equipment is negligible. The use and popularity of the 802.11g standard is also beginning to eclipse the older 802.11b standard. For these reasons — and because it offers faster speeds in certain situations — 802.11g dominates in availability, compatibility, and utility.
802.11n: Looking to the future
This yet-to-be-ratified standard specifies a data-transfer rate of 100 Mbps — equaling that of the wired Ethernet networks businesses use today. It will be backward-compatible with both b and g.
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Source:http://www.dummies.com/how-to/content/overtheroad-wireless-the-standard-frontrunners.html
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