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Email Over High-Frequency Radio in West Africa
Guillaume Filion writes "LinuxJournal has a fascinating article about Radio Email in West Africa over HF links. 'Deep inside the warm green interior of Guinea, centered in the frontal lobe of West Africa, field personnel in the widely scattered village-towns of Dabola, Kissidougou and Nzerekore now enjoy access to regular internet e-mail, directly from their desktops. Here we have bridged the digital divide, and there isn't a telephone line or satellite dish in sight.' Talk about Wireless Fidelity!"
A doctor could email a hospital of some symptoms in the field and get a reply of what the illness and proper care for it is. Although the individuals wouldn't get a benefit directly there would be an indirect benefit.
If you think education is expensive, you should try ignorance -- Derek Bok, president of Harvard
How does this system organize the data streams? What if two people miles apart transmit their message at the same time on the same frequency? How does it handle contention issues? They have an awful lot of bandwidth to transmit so the messages should be pretty "bursty" and fast unless they're downloading entire web pages and such.
I don't buy that at all. Although it would be nice, it will always be cheaper and more practical to, say, run a wire from your computer to your monitor than to have wireless hubs in each device.
It is certainly cheaper to go wireless than it used to be, and I think technology will help us get rid of some of the more restrictive and inconvenient wiring, but your prediction sounds a lot like the empty promises of old...like "someday everyone will drive a flying car", or "in the future, everyone will use conveyor belts instead of walking to their destination."
Technology obviously helps us in many circumstances, but much of the time it's just too expensive to be convenient.
...just my 2 gil.
Will computers still be so modular as they are today? I mean, the iMac has been around for a while and it's not modular. Even though I don't find them very aesthetically pleasing, I saw a single-unit computer the other day while I was looking for a new monitor, which I thought was really cool. It consists of a flat-screen monitor with the computer built into the back of it.
I think that computers will become less modular than they are now. (Probably not production computers like servers and whatnot, but I refer to user-end models.)
As for other computer-related things, like keyboards, I think wireless will also become more popular there. You said "it will always be cheaper and more practical" to run wires. Well, with wireless becoming easier and easier, "practicality" might be rated not on price of the unit in question, but on convenience. I, for one, prefer a wireless keyboard and mouse because I hate the wires limiting my mobility.
The other term you used is "cheaper." A device that uses wireless connections doesn't need a long cord. That's savings right there. And while wireless IS a touch more expensive to make right now, soon the price involved may be low enough that wireless is economically easier. Especially when you need multiple connections to a device. A TV (or other video device) needs several IN and OUT jacks to connect to all the things that people want them to connect to, like Antenna, VCR, DVD-player, etc. What if there was just one transceiver that could communicate both ways with all those devices? And your computer? And your WiFi remote? Forget directly programming your VCR or even your TiVo. You could just do it all through your computer.
You could run your whole house through your computer, without expensive interconnected wiring for everything. Have your computer turn on all your lights while you're on vacation. And if you get a new device, it'll already link with the rest of everything, so you don't have to run new wires even to a central hub.
I know, I know, it's what visionaries have been predicting all along, but now we can see a direct path from where we are now to where we could be. (Unlike with flying cars or ubiquitous conveyor belts.) I don't KNOW that this is the path that society will take, but I don't find it too far-fetched.
Any sufficiently simple magic can be passed off as mere advanced technology.
Wireless is fine for low-speed connections, or medium-speed connections that don't have to go very far, and can either interoperate between multiple users in the same space or else do some non-interference trick like spread spectrum. And it's really nice to have freedom of movement and ability to get some kind of service wherever you are, which means wireless in the most general case (though LANs with DHCP and VPNs are a good start.)
But fundamentally, wire-like technologies (including fiber as well as copper) are much more practical for high-speed connections, and can fit arbitrarily large capacity in a given area because separate wires don't interfere with each other, unlike multiple sets of radio waves. For high-speed connections over non-short distances, wireless needs line-of-sight, while wires don't need to be in straight lines, can leap under tall buildings at a single bound, wrap around mountains and curved planets, etc. Also, the physics for devices that mess with wires make it easy to put huge bandwidths on a fiber, limited by the cost of the high-tech equipment on the ends (which gets Moore's Law kinds of price/performance effects) - practical bandwidths get into the gigabit range for cheap short-distance equipment ($59 at Fry's) and into the terabit range per fiber for long-distance telco-quality equipment.
There is some relatively high-speed line-of-site equipment that can fit multiple separate connections in nearly the same space - free-space optics is the most focused, and there are microwave systems that are pretty tight. They can't do long distances, because of weather as well as because of the earth's curvature, but some of them are in the half-gigabit speed range over a few kilometers. They're really nice as a backup for building data feeds - they get rain fade, but they don't get backhoe fade, don't usually need permits to cross highways, and are surprisingly tolerant of earthquakes.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
It's being said in various ways in response to this, and I agree... wireless will never completely take over for wired solutions. In some places (top of a mountian with my laptop and handheld ham radio, or the article's mention of West Africa) it's better and easier than wires; in others (wireless phones) you can tunnel additional information on a single type of connection...but there are a few reasons wireless isn't going to take over.
Speed: Generally speed isn't very good on wireless connections. Show me how to get 100megs/sec out of any common wireless connection. This is the wired standard - but you need the bandwidth in wireless connections, and that leads nicely in to my next point:
Bandwidth: Anything wireless needs bandwidth. Generally faster means more data which means more bandwidth. There is a finite amount of bandwidth. It's pretty much maxed out already (In the US at least; there's lots of military applications, broadcast TV takes a chunk, radio, the ham bands, cell phones, satellite signals, radio astronomy...etc). There's only so much usable spectrum. To put it another way; what happens when your entire city/company/neighborhood/household runs on one connection (t3/t1/cable/dsl respectivly, just for the example)? you oversaturate the avalible bandwidth. Same thing would happen with wireless. If the entire country starts using HF bands for email; your avalible connection speed is going to be shared across thousands of connections...making checking your email a pain in the rear.
Cost: Look at the cost of a wireless NIC compared to a wired NIC of the same approximate bandwidth capabilites. Do they even make 10meg cat5 NICs anymore? 10/100 seems to be the standard, and even that is cheaper than a wireless card that only can do 11 megs at it's peak.
There are more but I'm tired of typing...just got back to the room after a long day in the rain. Message me or reply if you have questions or comments. Feedback is welcome!