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Peer-to-Peer Cell Phones?
Mike writes "This Wired article mentions that research firm SRI International has come up with a nifty way to lessen the need for the ugly cell towers that you see popping up everywhere (I love the ones here in Atlanta that are oh-so-cleverly dressed up to look like pine trees). Their PacketHop software would create a sort of peer-to-peer network, utilizing the unused power in phones in the vicinity as miniature relays, with your voice/data hopping from one phone to the next until it reaches a relay tower and its final destination."
Let me just say that these people would have to provide some pretty serious security credentials before I'd let my calls hop along other people's phones. Maybe they could PGP each person's phone. That'd be cool.
This tagline is umop apisdn.
My cell phone battery goes dead soon enough without transmitting data for other people.
If the number of cell towers were reduced and relied on proximity to other cell phones for a signal, would'nt that reduce the likleyhood of someone getting a connection in someplace like a national park or the Mojave Desert? People away from people need to talk to other people too!
Yeah, it's possible. Of course, it'd mean your cell phone's battery would run down within a matter of hours as it relayed other people's conversations around. I'd guess a lot of people would "hack" their phones to not act as relays, so as to conserve battery life. The result would be a breakdown of the network.
The multiple relay idea isn't such a bad idea, though, if you move the relays out of the phones and onto the power grid. How 'bout if everyone who got a phone also plugged in a base station at their house? That piece of hardware would do the relaying instead. Then battery life wouldn't be a problem. Offer a few people free service if there are dead spots in the neighborhood.
Add on another feature; plug the relay into your phone line, and when you're at home or near it, your cell phone becomes a cordless phone (like in L. Neil Smith's book Hope .
Very much like the peer-to-peer communication used by nanites in Neal Stephenson's "Diamond Age".
"We were half way to Rivendell when the drugs began to take hold."
-- Hunter S. Tolkien
but if you used cingular, could your hop conduct through att wireless phones, or even better, would one of the companies program them to use up their competitors' phones first?
::.. check out some Cell Phone Reviews
A system like that's gotta be able to reconfigure itself instantly, at "packet speed;" say I'm carrying some guy's packets and I drive into a tunnel... sorta like Gnutella on crack. Good stuff.
Wrists killing you? Not in 2 weeks. Learn Dvorak.
I guess if you're in a pissy mood and notice that someone is bouncing off of your mobile, you can shut it off in the middle of their conversation pretty much the same way people would shut off their Napster program whist you were downloading an mp3.
:)
/*drunk.. fix later*/
And if anyone wants pictures/more info on the new trend of disguising cell towers as trees:
h tm
http://www.signaltower.com/cellular_tower_tree.
Never ask a geek why, just nod your head and slowly back away. -Rob Malda
Anyone who's done any cellphone programming will know that there aren't an awful lot of spare CPU cycles going begging when the phone is idle, and there are hardly any at all when you're in a call.
Unless your phone has more CPU power than you need for normal use, and why on earth would the phone manufacturer do that?? - it'll just eat battery and make the phone uncompetitive.
Sorry, but you can't get this sort of system for free. It will cost, in more expensive handsets and/or reduced battery life. Not to mention a re-run of all the safety research as the things will be transmitting on a higher duty cycle even when you aren't deliberately making a call.
[Disclaimer: The above is all true for GSM systems as used in 199 countries of the world. I gather things may be a bit different in the USA.]
In addition, there's the problem that many people have already pointed out, which is that, by keeping the transmitter powered up at all times, you'd run down the battery faster. Not to mention that it might be impossible to make a call of your own while your phone was relaying someone else's call...
In other words, nice thought, but it's not really practical. (Yet?)
Eric
Be who you are...and be it in style!
How would this reduce the amount of traffic going through towers? The only traffic that wouldn't go through the tower is traffic that has enough turned-on phones running that software between you and the person you're calling. All other connections would hop through a few phones and go through the tower anyway. At best, local calls wouldn't need to go through towers. This would vary based on the density of cell phone users in your area compared to the density of towers. At worst, one's range or reception from a distant tower could be improved. Of course, there are also the security and power issues mentioned by others to take into consideration. Neat idea, though. Maybe if everyone had a cell-phone with a great battery and an impressive range, towers for local calls, at least, could be eliminated and used just for outgoing calls. So the cell phone network would be one of separate P2P networks connected by towers. That is, until the population is dense enough to send a call from New York to California.
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I had a similar idea but using particle entanglement as the transmission medium. I know the technology isn't there(and may never be) but bear with me a moment. Let's say you manufacture phones that have one million halves of entangled particles, preferably entangled molecules. If every eight particles is entangled with 8 particles on a different phone you can have 131,000 separate connections. Each of those phones would also have 131,000 unique connections. It doesn't take much to make a peer to peer phone network with such a setup.
The problem is that if such a communication device becomes feasible, will the manufacturers make them? Surely they would prefer a centralized model where the other half of the entangled particle resides in a network switching device so they can charge for switching.
OK now take this a bit further and you can make wireless network cards with unlimited range, keyed to a handful of other network cards. Next thing you know there is a growing peer to peer network whose infrastructure is virtually impossible to disrupt. Private networks can be created whose communications are impossible to intercept.
Cat
Add on another feature; plug the relay into your phone line, and when you're at home or near it, your cell phone becomes a cordless phone
I had a cell phone that came with a small base station that I plugged into my regular phone line. If someone called me on the cell number and I was within range of the base station, it would still ring the cell phone but connect via the base and I'd have no airtime charges. If I made a call from the cell, same thing.
The cell service was through the same company I had my regular phone service with. The thing I never thought of at the time is that I was never clear on what happens if I'm already on one of the lines and someone tries to call from/to the other line.
Nope, no sig
How 'bout if everyone who got a phone also plugged in a base station at their house?
...HOOOooYAH!!" - Duff Man
Or, as Bob Cringeley suggested, your car.
Your cell phone carrier could say: your service will cost $X a month, or it will cost $X-Y a month if you get a relay installed in your car or home.
"What Ever Happened to Fair Use?!
pi = 3.141592653589793helpimtrappedinauniversefactory7
Add on another feature; plug the relay into your phone line, and when you're at home or near it, your cell phone becomes a cordless phone
You know, I've been waiting for them to come out with a cell phone that was a cordless phone when within range of its base station(s). I'm sure it would be slightly larger than today's current crop of ultratiny cellulars, but not by much.
I'm sure it would be complicated but might even be worth it to come up with some way for the base station to add the cell line automatically as a conference party when you left base station, simulating a cell-cell handoff.
Heh.
Yes, it sends packets every once in a while.
Thing is, your battery has a standby time of 48 hours, but a talk time of what? 1 hour? 90 minutes? Most of that power isn't going to sound circuitry, it's going to the radio, and if your phone is busy relaying a call that radio will be pulling just as much power.
It wouldn't take much to hack a phone and be able to pick up the traffic being routed through it.
That is assuming that they are using a static route for the entire length of the phone conversation, which they most certinly will not be doing for the same reasons that they don't do it now. Think about it, if traffic is going through your phone, and you have your phone set up to your nice little hacking station in your basement, and you pick up a guy traveling on the highway with his phone, he will soon be out of range, right? If his entire conversation had to go through your phone, he would be cut off before he was finished talking. Just like if your entire conversation had to go through the same cell tower. Doing that would take the "mobile" out of mobile phone. The fact of the matter is, that each packet is likely to go through a different phone. The end result? You would get bits and pieces of several conversations, that would about to total jibberish. In fact they could even require it to route every few packets to a different phone, and thus eliminate the need for encryption. I hope all of you who are worried about your conversations privacy, suggest this to your telco.
Sigs are out of style, so I'm not going to use one...oh wait..
Every year the National Park Service spends millions rescuing idiots who do stuff like decide to hike to the bottom of the Grand Canyon with a cell phone but no water bottle.
Without wireless service in secluded areas, people who deserve to become statistics will do so without a hitch, rather than getting helivac'd out at the last minute because they happen to have their trusty microwave-emitting companion along.
Anyways, who the heck goes to an isolated area to talk on the phone?
pi = 3.141592653589793helpimtrappedinauniversefactory7
their business model is charging you per second or minute that you use the service. without going through a centralized system like cell towers they lose this ability.
very nice, but not gonna happen due to existing billion dollar companies not liking it.
Which, BTW, is one of the topics the IETF is working on... along with a ton of other researchers.
Thing is, your battery has a standby time of 48 hours, but a talk time of what? 1 hour? 90 minutes? Most of that power isn't going to sound circuitry, it's going to the radio, and if your phone is busy relaying a call that radio will be pulling just as much power.
Ah, not just a radio, a powerful radio (relatively speaking), with a shared resources system, the signal strength could be lowered, less drain on the battery, the signal range need only be as great as the distance between you, and the next phone over.
Which is where my whole point of sending a straighter signal comes in, rather than a wide area power wasting brute force attempt (pump enough juice into the transmitter to reach the tower), the range of your signal can be lessened to less than a few dozen feet in an urban enviroment. Pico-cells. Each one supports the other cell callers further from the nearest cell, extending in a chain of small spheres back to the tower, rather than one large sphere that wastes all kind of energy sending random radiation off in all directions as far as it can reach.
-GiH
There is no Sig.
If only everyone could buy a box for their rooftop that did this via 802.11b or a. Internet in the hands of the people. The problem would be getting on the wired part of the internet, but if there was a way for big business to take a part in this, it would make it pretty cool.
Too bad the range is so low on 802.11. If you could get 100 mile links out of it somehow, there would be little need for wires.
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God, why is everyone trying to apply the P2P paradigm to everything? Somethings just work better in a base-remote configuration. And I would guess that cell phones would be one of them. The only use I could see for this would be as a secondary mode for a phone to switch into to if it is losing the signal to a cell tower. All the phones would be in passive mode all the time, listening, and if a phone began to lose signal it could switch to a promiscuous mode to route calls over near by phones to get to the closest tower.
Cool stuff, really.
Actually, this concept is a lot more complicated than just the traditional packet-switching we see in the Internet today (although, it's not "new"). The network architecture implied here is referred to as an adhoc, or parasitic network. These networks have to dynamically update the network topology in real time in order to forward traffic appropriately, which is horribly more complicated than the internet we have today which is, in essence, statically routed. The development of these types of networks is currently a hot topic in the networking research community, since there are a number of interesting applications.
Isn't this more or less how Ricochet used to work?
News for Nerds. Stuff that Matters? Like hell.
for most people.
Let's face it, we can't share. Nobody here was taught how to share their toys, or play with others. The comments suggest that, and I believe that most people just really can't share. We're all too focused on ourselves to care about others...
This would reduce average power consumption of phones!!!! You would actually have MORE talking time then less. With more antennas, the power required to talk on the network would go down because you wouldn't have to waste all that power trying to talk to a cell tower miles away, as the closest 'tower' (cell phone) would be like 300 feet away.
Do you realize that power required goes up as the cube of the distance? If you want to transmit twice as far, you need eight times the power, that's what it means. So instead of requiring watts of power when you are talking, your phone would require milliwatts all the time (a hundred times less then today). Shut off backlighting and you don't have to worry about it.
This will never take off for the same reason that gnutella will die if we are forced to pay for bandwidth.
Cybiko - it's not great, but they have done it.
... Can you... damn dropped call!"
Here is their site if you don't remember this POS. (I've never tried one... sounds cool but no one has one to hook up with)
The question is: Are we going to be seeing the verizon guy going around standing next to people on cell phones saying "Can you hear me now? Damn!
Get your Unix fortune now!
Maybe, if you can find a way to boost ;-)
:-)
this up a little.
That, and you can help me in spreading the rumour that exposure to very low frequencies at high amplitude for prolonged periods of time causes impotentcy. If this rumour is properly spread to urban legend proportions, I'm sure the problem will cease. No song will be worth blasting if the fear of erectile disfunction is properly spread.
If people will believe that green M&Ms can turn people into homosexuals, they will certainly take this as gospel.
/*drunk.. fix later*/
We have all seen how P2P networks function: usually it's a select few subsidizing the masses who are unwilling to share their resources. People are greedy. Non-geeks are even greedier. Most of the general public wouldn't understand how the idea of using many phones as a relay in a distributed fashion would provide them with their service as well.
Not to mention some technical problems -- look how reliable cellular service is now. Even in very well covered areas, call drops from all ranges of carriers and all types of phones are common enough to be annoying for most people. A Peer-to-Peer cell network would be even more unreliable than the current infrastructure, which would force the need to be verbose with things like repeating data to several relays at a time to minimize points of failure. It might work if you had several dozen relays all capable of working for you -- but that's not an efficient use of bandwidth.
It's helpful to remember that all the phones must share a single pipe which is the air in the frequency they operate in, so there is a finite amount of bandwidth available so it makes sense not to waste any. This is in contrast to p2p on the internet where each host has its own dedicated and usually unshared circuit and more bandwidth can be added by adding more wire.
What is to prevent people from turning their phones off to save the battery, and if that is impossible, taking the battery out completely? What if there are three phones active and only two relays available?
What about the situation where there is a low population density and thus even lower phone density? Is this a solution for urban areas only?
Even in urban areas, demand is going to increase and put more stress per phone on the network.
Clearly p2p isn't going to work for cell phones for some time. What the wireless companies need to do is get together and establish a grand this-is-it standard that allows any phone to be used on any network. There are enough providers that the cost of infrastructure development could be spread evenly across the market. This idea is flawed both in the social aspect and technically. Plus in a day when people are increasingly carrying phones around for emergencies, would you want the kind of reliability as afforded by Kazaa, an already developed p2p application?
"I'll just chip in a bit for RedHat: I actually have that installed on my university machine." - Linus, '95
According to the article it seems that their only real selling feature is to increase the robustness of a cell network without having to add additional towers. There might be other reasons to have P2P enabled phones but this one is just plain silly.
First, this would only really work in well-populated areas with high densities of regular cell phone users. But these cities are already very likely to have a strong saturation of cell coverage, and it is probably relatively economical to install new network towers in such high density areas.
Second, if an emergency occured, a la 911, where the load is exceptionally high, I can't imagine this system of low powered devices holding up anywhere near as well as a decently saturated network of towers (that also have a lot more power). The decentralized network might be theoretically more robust, but not if everybody's trying to make a call at the same time and not when the device range only allows for a very limited number of localized connections to form.
Wireless P2P and multi-hop) systems are really cool, but it's not going work for everything or solve every problem. One day they may become ubiquitous, but are likely to be first employed for niche applications only. Cell phone applications and benefits will probably be limited to local network communications.
Maybe such a system could one day be used to help improve coverage deep within buildings, or for very localized load balancing, but I doubt that they will or should be trusted technically as an alternative to building an independently robust network of towers etc. And, if they are only proposing the technology as an adjunct for increased reliability, then I just don't see a very strong business case.
My next sig will be ready soon, but friends can beat the rush!
Each one supports the other cell callers further from the nearest cell, extending in a chain of small spheres back to the tower, rather than one large sphere that wastes all kind of energy sending random radiation off in all directions as far as it can reach.
The biggest factor in power expenditure is the ability to put the device into standby mode. The transmission power has relatively little relevance. If the device has be a routing node in a mesh network, it can never go into standby. Even if there is no traffic to forward, it will have to keep exchanging routing information with its neighours, in order to be *able* to forward traffic. This will suck the battery dry in a matter of hours.
Not to mention the other equally inexplicable down sides:
1) security - intermediate nodes can tap your calls
2) security - intermediate nodes can reroute or prevent your calls
3) quality - packet loss for a number of consequtive wireless links would be stupendous
4) quality - cumulative delay from a number of consequtive links would be disastrous (more so, if link layer retransmissions were used to improve packet loss)
5) you've got no neighbours, you've got no calls - where do you get the people who are willing to stand in a chain between you and the tower, while you yabber on with your girlfriend?
6) would you pay for that service? Would you trust the intermediate nodes to meter your call? Might be a few surprises in store when the bill arrives...
"I have opinions of my own, strong opinions, but I don't always agree with them." -- George H. W. Bush
Huh?
Instead of "own" think of "0\/\/|\|". As in "~~***\/\/3 0\/\/|\| j00!!!***~~" (those are all zeroes, not ohs).
You make the same assumption as some others who resist cell phones: having a cell phone means you are required to answer each call. What you call interruptable, I call available. You always have a choice as to whether or not you want to be interrupted.
When I'm meeting up with friends -- especially at a club where it's hard to find people -- it's extremely handy to be able to call them. When I'm in a movie theatre, it's on vibrate and I'll usually ignore it if I don't have some reason to anticipate an urgent call (no wife, no kids). And if I'm intimately engaged, you can count on me ignoring it, thank you very much.
I'm always surprised when people ask me with surprised shock, "You're not going to answer it?" if I check the caller ID and decide to let the voice mail get it. If I'm having a conversation with someone, the other person can wait their turn. It's the same etiquette that would keep you from interrupting two people in a lively conversation unless you felt welcomed or just wanted them to pass the salt. In this case, the caller doesn't know, so I make the decision.
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I guess the War on Terror really is about freedom!
Basic truth: for reliable low-power communication, at least one end of the link needs to be well-sited. That's why cell phone towers are positioned carefully. Even setting up an 802.11b network requires that the base stations be positioned in reasonable locations.
You can blast your way out of that limitation with power (the military solution), or only expect it to work in areas with very dense node populations (the urban WiFi solution).
This idea was looked at back when mobile phones were attached to cars. Back then, power levels were higher, battery life wasn't a problem, and antenna locations were better. Even then, it wasn't that attractive.
Amateur packet radio works something like this, but even there, what makes it all go are VHF repeaters sited on high places.
GMDSS, the Global Marine Distress and Safety System, really does work this way. Marine radios, since 1999, have had a big red "DISTRESS" button. Pushing this sends out a message that gets forwarded by every other ship that has GMDSS gear. But that's a specialized, low-bandwidth application.
The small-but-noticable delay caused by the encoding/decoding process is already as bad as is usably possible. Adding packet-hopping to cell phones would increase this latency by a noticable degree, making them less usable.
I know cybikos are not cell-phons, but they do implement a similar packet-hopping technique. see Cybiko.com
P2P packet radio is an old idea. Check out the old Aloha and AX25 protocols. One of the best sites for amature packet radio is Tucson Amateur Packet Radio or Packet Primer.
Clearly anyone who believes this is an idiot. It's the blue M&Ms that are gay. And the M&M people are still holding the tan M&M in solitary confinement without a lawyer or other advocate. As others have said, the newer blue M&Ms are much weaker and are genetically inferior to the other colors.
I'm an American. I love this country and the freedoms that we used to have.
I've seen several comments pointing out that reduced battery life as a serious issue...
Here's another one: Signal degradation.
Anyone with experience in networking knows that while repeaters can be used to extend the maximum length of an Ethernet run, you can only repeat the signal so many times (4, for Ethernet, IIRC) before data error become an issue.
I paid for a Motorola Startac back in the day... $250 for a cell phone, and even with such a nice cell phone, loss of quality is pretty noticeable when compared to a landline... Wouldn't hoping the signal through 3 or 4 of these make for pretty horrible reception?
It's possible the loss of quality due to some other aspect of cell technology that I'm not aware of (digital signals and compression, perhaps?) I'd love to hear from someone who knows more about cell technology.
I'm doing my masters thesis on bluetooth ad hoc mobile routing, and one thing I can say is it is not easy to setup and maintain a routing structure. If you have a sparse distribution of nodes, you may run into connectivity problems, although the algorithms for routing become fast. If you have a dense dist, the routing becomes increasingly toughter, as you will have more pico-nets, gateways, clusterheads, and routing tables to deal with.
Scatternet formation has to be done with a distributed algorithm, since, at the start, no node knows where the others are. There are many more problems with a network like this, for information transmission, like latency, reformulation of the network when nodes move, or are turned on or off.
Now, if cell phone protocols were changed, ie, new cell phones were built to use ad-hoc networks, with cell towers as fixed access points and gateways, the idea will have a good future.
The major stumbing block, and why this idea cannot immediately go to cell phones, is the notion of band-split and the fact that the cell-phone network is fundamentally circuit-switched (as alluded in the article).
Mobile devices are licenced to transmit on certain frequencies and receive on another set. The base station (at the tower) has the opposite band-split. That's how a full-duplex connection is made. One can listen and talk without having to push a button like a walkie-talkie since there are two separate radio connections used together simultaneously. Mobiles typically transmit on the low side of the band and base stations on the high side.
In order for a mobile to act as a base station (for the purposes of repeating or P2P), it would have to implement the radio hardware to do listen to other phones, like a base station does. Besides the licensing issues, cell phones do not offer this extra-cost (and potentially bulky) RF hardware.
The P2P cellphone idea demonstrated on 802.11 has a fundamentally different RF architecture, where one band is shared in a multiple-access fashion. It's also inherently a packet-switched technology. In 802.11 band-split is not an issue for P2P.
Anybody want a peanut?
How do they do packet routing?
Imagine a very dense area of repeaters and a tower. Phone A can't talk with the tower but a lot of phones can and moreover there are a lot of phones that both A and the tower-able phones can route over. Is there some form of "Yes, I will route for you" that cascades up the tree and first-come-only-served? So if A can hit B can hit C can hit the tower, then A sends a request, B gets it, broadcasts it *again*, C gets it, knows it can hit the tower, responds to B, which then responds to A?
Anybody know how this really works so I don't have to pull ideas out of my ass? ^_~
Anarchy$ dd if=/dev/random of=~/.signature bs=120 count=1
Something like this won't really be pratical until battery life has far exceeded current standards. The difference in battery drain in stand-by mode and in-use mode for most phones is significant, I expect that this would drain batteries in a manner more like the latter rather than the former. As a result, I doubt that it could be implemented in any sort of practical manner at the present. . .
Just what I want... a high-frequency transmitter randomly tossing out EM radiation while sitting in my pocket right next to the family jewels....
Don't fool yourself... SRI is trying to sterlize us.
And such a wonderful job P2P does too. You've already heard about the power issues this would create in a phone. Using those "unused" powercycles means you won't be using them later on. A cell battery is a very finite resource. Which would lead to another quite famous P2P problem: Sharing. It's no large stretch of the imagination to see people turning their phones off as not to waste the battery on these extra cycles, only turning them on to make a call. Or here's a good one-- Lag while the phone attempts to sort a path to the nearest main node. You think those MP3 searches take a while sometimes? I'll stick with my Nokia, thanks.
You need a FREE iPod Nano
My cell phone is often on a charger, either at home or in the car, so no problem with battery drainage. No doubt being used as a relay would be an opt in proposition with many settings like your laptop sleep and idle modes. For instance, only relay while on a charger, only relay while over 50% charge, only relay 50% as many calls (power equivalent) as actual usage. Etc...
Users to be rewarded by relay discount points in their bills (think frequent flyer miles).
Encryption no more (or less) needed than regular phone. Why hack your relay phone, when you can just buy a scanner?
Maybe my phone will work in this near underground apartment, relaying though the phones above, then out.
More available bandwidth, more calls can get through, by using smaller, but more numerous relay towers, that are closer together, or hop around a tower that is saturated, like often happens Friday nights in this College town.
Huge events (or disasters) less likely to completely jam network (continue hopping until getting to an unsaturated tower).
Mini towers possible, by tying phones into land-lines or cable modems. Again, a customer discount or credit option.
With a diffuse enough network, and mbone like simulcasting, 4G services like mobile HDTV.
Cellphone network compatible laptops should hardly notice the relay drainage, compared to regular greedy CPU use.
Letter To Iran
My credit card number is 421766..... wait... wait... wait... I hear breathing on the other end of the phone line. Oh, that's you? I forgot I was calling a phone sex number...
Can you hear me now? Good!
/^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/i