The whys and wherefores of the Wi-Fi future

Rupert Goodwins: New networking standards will soon be on the shelves, but patience is advised before taking to the air.

I've decided that the real reason computer people call bunches of signals 'buses' is that you wait ages for new standards and then two come at once. Take wireless networking, which once upon a time produced new standards once every decade, if you were lucky. Now it seems that we've only just settled down to nice Ethernet speed 802.11 when we're being asked to upgrade to 55Mbps -- and just for fun, we have to choose between two non-interoperable standards.

In case you don't like keeping strings of nearly identical numbers in your head, here's the rundown: 802.11b is the current standard, running at 11 megabits a second in the 2.4GHz band. 802.11a is 55Mbps in the 5GHz band, and 802.11g is 55Mbps at 2.4Hz. For now, the standard that's going to be pushed most heavily is 802.11g; it'll be cheaper and, say the makers, more compatible with existing networks. Going five times as fast sounds like a good idea, but it may not be all gravy.

Assuming that the standard works perfectly, then most of the time the extra bandwidth won't be used. If you're using your wireless link as most people do -- laptop Web surfing -- then your Internet connection is going to be much slower than even 802.11b. (If you're using a multi-megabit leased line straight to a major ISP backbone, then go ahead. Buy the darn stuff). Multiplayer games, moving files between your computers, watching video and so on might seem like better candidates for high speed improvements, but most of the time it'll be unnoticeable.

One area where it will count for a lot is with multiple streams of high quality video. This is in your future: the new TiVo hard disk video recorders will have wireless networking as an option, and will share files among themselves in a multi-TiVo household as well as playing back media on your PC. If someone's trying to watch Buffy in the bedroom while Delia's playing in the kitchen, 802.11b isn't going to cut it.

That's the upside. The downsides are more serious. For a start, although everyone's pretending that 802.11g is a standard, it isn't. Not yet. It will be by the summer, but for now it's still in draft. Compatibility between 802.11g chipsets -- and between them and existing 802.11b cards -- is not yet guaranteed, and the certification process not in place. And while 802.11g manufacturers make a big thing about cross-compatibility, saying that you don't have to upgrade your entire network at once unlike with 802.11a, they skate over the fact that until you do, you're stuck at the old 11Mbps rate. Because 802.11b and 802.11g use the same frequencies, you can't run both protocols at the same time, and one slow card in the network will force all the rest to its speed. It's probable that by the end of the year, tri-mode cards capable of operating on any standard on any band will be common, and that over the next year or two all new products will do this -- that's what happened with 802.11b as it took over from the 2Mbps 802.11.

Security in the new standards is no better than for 802.11b either -- in fact, all the wireless standards have flawed encryption and authentication schemes. That'll get better later this year when Wi-Fi Protected Access becomes available. That will have two modes, office and home, with the office one requiring a proper authentication server. Home mode doesn't need this; you'll just tell the access point a password and then make sure all the other nodes know it. Once this comes out, you'll want it -- and quite possibly the related 802.11i security standard which is due at the end of the year. It's just arguable that 802.11a will be slightly more secure than the others, because the higher frequencies don't penetrate walls and floors as well as 2.4GHz, but no security consultant worth their salt would regard that as anything other than the very lightest dusting of icing on the layer cake of security.

Whichever way you cut it -- stop thinking about cakes now -- there is no good reason to rush out and buy high speed wireless networking today. Some of you will, of course, just for the fun of it, and that's to be roundly encouraged. I shall be one of your number. But for the sensible out there, hold hard. This time next year you'll be able to buy something that goes fast, is as safe as houses, and works with everything else. Your call.


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