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T-Mobile Announces WiFi Meshing Cellphone
tregetour writes with a link to a New York Times article penned by David Pogue about a quiet announcement last week by T-Mobile. It has nothing to do with the iPhone, but it could still be a welcome revolution for users plagued by high cellphone bills. "Here's the basic idea. If you're willing to pay $10 a month on top of a regular T-Mobile voice plan, you get a special cellphone. When you're out and about, it works like any other phone; calls eat up your monthly minutes as usual. But when it's in a Wi-Fi wireless Internet hot spot, this phone offers a huge bargain: all your calls are free. You use it and dial it the same as always — you still get call hold, caller ID, three-way calling and all the other features — but now your voice is carried by the Internet rather than the cellular airwaves." He goes on to explain further benefits of the system, and describes the wireless routers that the company will be pushing with the service. The only thing missing: an estimate of when it will hit stores.
How about last week... when it actually hit stores? Anyway, it's just too bad that existing phones with WiFi like the Dash don't support this.
Yeah, but how exactly is it a mesh?
What does this have to do with the iPhone? I mean, I know the summary says it doesn't have anything to do with the iPhone, but I'm not sure what that means. Did Apple figure out how to do this? Are they working with T-Mobile to roll it out? Are the phones made of white plastic?
Like the rest of the Slashdot community at this point, I decided this summary was worth my time only after I discovered it had nothing to do with the iPhone.
Umm.. You still use tmobiles network. The call doesn't magically travel across the country and terminate at another phone.
Have you ever been to a turkish prison?
Most coffee shop deployments will not die on bandwith. They will die on packet rates. One VOIP call is 100 packets per second. 8 calls are 800. While the nominal rate of most devices used for APs should in theory allow 10+ times more than that, in reality they will die NAT-ing the traffic. 3-4 calls at most is what they can handle without excessively jittering the flows. 8+ calls is likely to kill most APs with built in NAT outright. 8 calls assuming IPSEC in UDP NAT traversal and AMR internally is around some measly 320Kbit. So packet rates start killing this long before bandwidth is of any concern.
While there are few of these phones, they will be great. If they really get market penetration its own popularity will kill it or make it useless as it will be switching to GSM/3G all the time due to detected congestion on the WiFi. From there on there will be endless billing nightmares as consumers will insist that they called over WiFi while the call really was routed over cellular and so on and so fourth.
It will be fun to watch. From the sidelines. Thanks god I am no longer in this business.
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Let me preface the rest by stating I work in T-Mobiles Operations and Engineering Department, and helped alpha test this device. =) When making a Wi-Fi call, the handset creates a GSM tunnel allowing it to maintain the same security used on any normal cellular call you make. So if you're still afraid of people tapping your calls, I recommend that you don't use a cell phone at all. No releasing it at the same time as the iphone doesn't seem like the best bet, however I'm not in marketing ;)
One of the major advantages of this over a normal wi-fi phone, is that it will hand over between GSM and Wi-Fi and maintain the call. No other Wi-Fi call provider can offer that at this time (AFAIK).
If you buy the phone but not the service, you can still use Wi-Fi but it will use your minutes as normal, the feature just give you unlimited Wi-Fi calls.
Will it make calls for T-Mobile cheaper to process? Maybe if enough people start picking it up, but there was an investment in time and added hardware to the network that would need to be paid off first. But in the long run, yes t-mobile should save money as people route calls over IP, however, this savings is passed on to the customer in that they can make all the calls they want for $10 a month. (It's up to the customer to decide if they will use it enough to warrant that cost)
Working for T-Mo I think this feature is great, but my opinion is of course biased.
You pay "extra" because T-Mobile still has to operate a voip server and route your call. But those of us who make lots of calls from an area with wifi coverage can save money by changing to a plan with far fewer minutes and adding the $10 wifi option.
This is an outstanding development if you use your cell as a primary line and you have wifi at home. I hope it delivers as promised!
The biggest problem with mobile wifi is hand offs. It's been a while since I've looked into the issue, I know there were a couple of MIT guys working on millisecond hand off from one hotspot to the next a year or two ago, but the power consumption was huge.
Cellphones don't have to handle hand offs, the towers do all the work. I had a job doing a lot of testing of call hand offs a few years back. You literally drive back and forth between a few towers, or in a bad hand off area (especially around lakes) and work on programming the towers as to when they should hand calls off to another tower based on vector, signal strength, and a tower list. The whole thing is dynamic too, so weather changes, call volume, new construction, etc... can all be handled at least in the short term with out further work.
I know Sysco has some really cool auto-meshing technology that makes their routers talk to each other and adjust signal strength to pick up for downed antennas, but that technology would have to mature a lot to get the same kind of hand off performance as cell phones enjoy.
-Rick
"Most people in the U.S. wouldn't know they live in a tyrannical state if it walked up and grabbed their junk." - MyFirs
Which would probably be totally true HAD THE ARTICLE NOT SPECIFICALLY STATED that you could use your phone FREE at Starbucks T-Mobile hotspots!
I can attest, it changes over from VoIP to cellular tower seamlessly, with no noticeable change.
I start my calls while standing or parked next to a Starbuck's, drive off, and the entire call is free.
I use this Hotspot@Home service and find it fantastic! T-mobile already offers the best customer service, now I have a cell tower in my bedroom...and free wifi roaming while overseas.
The Good
-WiFi call quality better than GSM
-WiFi-GSM hand-offs work well
-No minutes charged for calls started on WiFi and finished on GSM
The Bad
-Will not work with hotspots that require a web log-in (aside from T-mobile USA Hotspots)
-The bundled router does not support Mac OS X (to register you need to run a Windows-only application from a CD)
The Ugly
-The service currently works with only 2 very basic phones that even lack a web browser...even though high end devices like the Dash have wifi chipsets
"...What is good for General Motors is good for America." -Charles Wilson, Secretary of Defense and fmr President of GM