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802.11 vs. 3G For Mobile Access
bobdole34 writes: "A new way to give us fast mobile net access spells further trouble for 3G.Imagine being able to surf the net at speeds faster than DSL from anywhere, at any time - you could watch a live video webcast while waiting for the bus, email photos to your friends while sitting in the park, or download the MP3 of the song that's playing in the pub before it finishes. I smelled vapour until I saw a demo of MeshNetworks at 802.11Planet in Philly."
Connecting things in a mesh is all good and well and certinaly more efficient - but is it efficient enough?
:)
Wireless networking occupies a relatively narrow band of the frequency spectrum, and probably less than the 3G ranges offered to telcos.
I highly doubt that an 802.11 mesh will ever provide that much bandwidth - especially once things start relaying in many directions at once.
Imagine splitting it up into cells, each one where a user is. As something transmits from one cell to the next, it'll use bandwidth (or available frequency space) in the neighbouring cells.
Anyway this could work for dense areas but screws over the people living in the country - worse still, it's not dependable. What if you need to make an emergency call and nobody is within range?
I heard nokia were wokring on a hybrid tech that allows you to use mesh networks when they are around and 3G otherwise - that would be cool
Also i could raise the usual problems of accounting for bandwidth use on this kind of net - who pays for it all?
Sure eveyone will be worried about sniffing traffic but good crypto might take care of that. What normal people are really going to care about is battery use. This is going to drain the devices battery. Will people simply opt out of the network by leaving their device off till they need it so the standby time is not cut down?
I might actually motivate and get a new cell if it came with something like this. Of course convincing the phone makers to put it in might be a little hard considering how inbed they are with the telcos. God this country is so behind in some respects. Anyway, since the telcos seem to want to charge me an arm and leg everytime I access their crappy wireless net services I would be a big fan of being able to just tie into a mesh network for cheap. Of course one wonders about the powerdrain for people leaving their phones on in their pocket/bag and having them used as routers. Can't be good for battery life. Guess I'll have to wait for fuel cells afterall.
There is no billion dollar market for wireless web services, and their won't be until it is cheap and easy to use. I.e., years from now, possibly longer.
Power.
Think about it. You plug a wifi card into your laptop and start surfing. Battery life cuts from 4 hours to 2.
This study examines current 802.11a solutions... chances are there will be some improvements, but it averages 100 microwatts/sec regardless of whether it's in use or not.
OTOH, 3G phones (with their tiny ickle bodies and tiny ickle batteries) consume power at 25 microwatts in TX/RX, and only 1 in idle mode.
This article talks about how 3G power is a challenge for handset manufacturers even now, designing for 3G. You think your phone is gonna be able to cope with 802.11a? You're wrong.
3G and WiFi are both cool. But they are different.
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Much more important is that in practical terms, the bandwidth of the airside isn't the limiting factor in a public-access network. In an office environment, you can get something like 3.4-4Mbit/s out of 802.11b (depending on your adapter, and on whether you are using WEP encryption). In a public-access network, you've got to pipe that down some back-haul pipe to an upstream PoP. Either you use cheap-and-cheerful 2Mbit/s DSL, and put up with contention at the DSLAM, or you pay for something like a T1/E1 with dedicated bandwidth. Even if you pay for the dedicated bandwidth, you're probably going to end up with at most 2Mbit/s shared between your active customers.
You'll have to check prices yourself, but it's difficult to see how you can make a profit unless you dimension the system for a fairly low target bandwidth, say 256kbit/s, when you cost in the bandwidth and the installation labour. That makes it much closer to 3G in practical terms - probably a bit faster and a bit cheaper, but with access restricted to hot-spots.
Ok, first you gotta realise that 802.11b (even) by access standards is fast!
With a contention ratio of 50, and giving each user 576K you get:
11,000,000 / 576000 * 50 = 954 users
That's on a single connection, within say 100m of some user.
So even 11b can allow enormous numbers of people 'broadband' capabilities.
Secondly, that's with current technology only- a more advanced technology would allow multiple networks on the same frequency by using directional aerials- this can multiply up the usage maybe 20 times. Then there's the fact that even 11b allows atleast 3 different channels (in practice). We're talking thousands of people, potentially,in little old 1b land alone.
Anyway this could work for dense areas but screws over the people living in the country - worse still, it's not dependable.
Yes, this is the issue. WiFi is basically line of sight, or 100m range. However that's a regulatory issue, mostly. The only reason that WiFi is so restricted is due to power limits. If the users were allowed to shout louder, they would be able to go further, and then country people would be in range of each other anyway (chances are).
What if you need to make an emergency call and nobody is within range?
Cell phone? Who says WiFi is for emergency calls anyway?
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"1. The Telcos start whining to their regulators that they are being deprived of revenue, as point-to-point trunk calls lessen for 802-based communications.
2. The wireless carriers (who still haven't found a stable, profitable business model -- i thought PacBell Wireless was bad -- until Cingular bought 'em) will join in with the trunk owners and scream that their FCC franchise is being devalued by Wireless IP Data and IP Telephony and they need government help (read: R-E-G-U-L-A-T-I-O-N) right now.
3. The Consumer Giants will whine and bitch and snivel about interference issues with 2.5 and 5 GHZ devices they make.
4. The law enforcement/intelligence community will endlessly bitch about their lack of ability to "monitor" this dangerous new technology, and how this creates a national security vulnerablity and therefore, offers a "window of opportunity" to evil-dewars. They will insist on lousy/key crypto and 1.5 bit key algorithms, and their ability to "oversee" the security of this spectrum.
4. The G, sensing the increased value of this spectrum and their ability to make even more money in licence fees and regulatory overhead will further regulate the spectrum and cause more and more expense to be made to justify their jobs and administration and regulation of it.
no wonder i don't sleep much.....
Ten quid, she's so easy to blind. And not a word is spoken...
"A new way to give us fast mobile net access spells further trouble for 3G.Imagine being able to surf the net at speeds faster than DSL from anywhere, at any time"
I could imagine that, except I can't get DSL out here, and likely won't be able to at least until the end of the decade. I'm assuming you mean by very limited definitions of "anywhere." More like "anywhere you would care to be."
"you could watch a live video webcast while waiting for the bus,"
"Bus" = "Public transport" = "population density" = "not me."
"email photos to your friends while sitting in the park,"
"Park?" Another one of those things that suggests population density. See, out here we have these things called "back yards"...
"I smelled vapour until I saw a demo of MeshNetworks at 802.11Planet in Philly."
802.11 is a wireless LAN technology. Do I need to remind you what the "L" in "LAN" stands for? Rigging up local transceivers for a single building is a heck of a lot simpler (and cheaper) than an entire city. And that's only for you folks that live in cities (read "for those of you that matter" as far as just about everybody seems to be concerned, even on here).
On the other hand, 3G is essentially a WAN technology, with its much wider tranceiving radius. It may be a cold day in Hell before BellSouth gets off their good-for-nothing behinds to upgrade the local switches for DSL (let alone somebody setting up 802.11 WAPs every few hundred feet along US 90... not that I live close enough to 90 to begin with...), I at least have some access to Sprint's network out here.
I'm sorry, but trying to say that 802.11 can and will compete with G3 is like saying that Gigabit Ethernet is going to edge out the T-3 market.
Oh, and before somebody brings up how Canada has DSL "everywhere" with their larger land mass and smaller population, ever wonder why the United States seems to have twice as many meters of paved highways per person than Canada? Maybe because the Canadian population isn't as dispersed as the American population?
Having looked over and drooled over some of the latest, greatest wireless offerings such as ATT's "mlife", I got to the point where I read exactly how much they charge for the service. They are kidding with these pound-me-in-the-ass prices for data, aren't they?
Here is a great technology just waiting to be used, and they brag bout downloadable games and video and music and they best they can manage is $12.50 for 2MB of data per month? Isn't all the data coming from/going to the phone digital data anyway? At least it's cheaper (and better) than the Palm VII's Palm.net service and that was cool in its day was well.
The more power to the people who start these mesh networks, the better. Prices need a little bit more downward pressure.
I tried every decent and legal way I could think of to resolve the issue w/the business before I rented the chicken suit