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Femtocells To Replace Parts of the 3G Network

CmdrTaco posted about 4 years ago | from the can-you-hear-me-now dept.

Wireless Networking 83

sweetpea23 writes "Grown-up versions of femtocells — devices which beef up 3G network strength in the home — are set to take over parts of the outdoor cellular networks, according to technology vendor picoChip. Femtocells — such as Vodafone UK's Sure Signal device — are cut-down versions of mobile phone base stations, redesigned to operate inside buildings, using home broadband networks to route 3G data onto the Internet. Now, picoChip, which claims to provide 70 percent of the chips used to make femtocells, has unveiled a toughened up version, which takes the femtocell idea back out onto the streets."

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Where to buy? (1)

theaveng (1243528) | about 4 years ago | (#33574248)

"femtocells -- devices which beef up 3G network strength in the home"

Never heard of these gadgets. Are they expensive? Large in size?

Re:Where to buy? (2, Informative)

sheddd (592499) | about 4 years ago | (#33574310)

AT&T is selling something like this for $99 [att.com] . I'd like to have in my office, but haven't purchased yet; limited to 5 phones and you have to register the phones on the device.

Re:Where to buy? (2, Informative)

colfer (619105) | about 4 years ago | (#33574622)

The range is not great. ATT says 40 ft, which is about what we got. Other than that, works great.

The limit is 4 phones operating at one time, and you keep a list of up to 10 approved phones.

The weirdest thing is it has to get a GPS signal to activate.

And why microcell vs. femtocell?

Re:Where to buy? (1)

sheddd (592499) | about 4 years ago | (#33574700)

Thanks for the review & corrections; I think I'll get one :) 0-1 bars in my office.

Re:Where to buy? (1)

maeka (518272) | about 4 years ago | (#33576294)

The weirdest thing is it has to get a GPS signal to activate.

Gnats-ass time-sync.

Re:Where to buy? (2, Interesting)

PitaBred (632671) | about 4 years ago | (#33577014)

Not really weird. It's probably a legal requirement to have a GPS location of every cell on the network. AGPS, cell phone tracking and all that. The police wouldn't be happy with you being able to make cell calls from any network connection without being traceable, and AT&T probably wants to prevent overseas use as well.

Re:Where to buy? (1)

Kryptonian Jor-El (970056) | about 4 years ago | (#33577096)

I think its more likely that they don't want people taking these overseas to use to make cheap calls to the us

Re:Where to buy? (1)

Petaris (771874) | about 4 years ago | (#33578428)

Verizon has one too. They claim the GPS is for the 911 service routing.

Re:Where to buy? (1)

Bert64 (520050) | about 4 years ago | (#33577494)

The GPS signal is to stop you taking the device to a foreign country to avoid roaming charges...

Re:Where to buy? (1)

maeka (518272) | about 4 years ago | (#33578410)

And the dual GPS antennas on (literally) brick-and-mortar telephone switch-houses is for???

Re:Where to buy? (1)

d-ude (106541) | about 4 years ago | (#33579658)

Timing purposes more than likely. GPS offers much more than just location services...

Also, the Femtocells use the location data to coordinate frequency usage so as not to interfere with nearby cell sites.

Co GPS (1)

danknight (570145) | about 4 years ago | (#33580274)

Office timing signal. much more reliable and accurate than SS7 copper or fiber links

Re:Where to buy? (1)

sideshow (99249) | more than 3 years ago | (#33716126)

The weirdest thing is it has to get a GPS signal to activate.

This makes sure you aren't full of shit when you put in the device's physical mailing address. When you call 911, att wants to make sure the paramedics go to the right place. If the address doesn't match the GPS cords, then the microcell doesn't work.

Re:Where to buy? (0)

Anonymous Coward | about 4 years ago | (#33574466)

Just about a size of a cable modem. I got one for a while to test it. I am not sure it will be very useful here in eastern Europe since it's pretty much sure that you first get 2/3G coverage and then comes the broadband. Maybe in US it will be cool to have it in the rural areas.

Re:Where to buy? (0)

Anonymous Coward | about 4 years ago | (#33574988)

they are very small (router size). Verizon, Sprint, and AT&T have them.

http://www.verizonwireless.com/b2c/store/accessory?action=gotoFemtocell

Verizon's routes other people's calls through it. AT&T's routes only your calls. I do not know about the sprint one.

T-Mobile uses UMA at last report to achieve something similar.

--Sam

Re:Where to buy? (1)

SimonTheSoundMan (1012395) | about 4 years ago | (#33576034)

We already have such technology. It's called, umm, wifi.

Re:Where to buy? (1)

onceuponatime (821046) | about 4 years ago | (#33581064)

These things are a bit rubbish. At least tonight it is. I bought one today. I can see that it establishes a VPN connection with nat tunneling. But stlll the fourth light doesn't come up, which means it's ready for use (Vodafone sure signal, UK). I did see it flash the fourth light, implying it is updating the software, then it went through a phase akin to a reboot. But not it mostly exchanges lots of ESP encapsulated packets and tons of NTP transfers and no availability. I'll see what it does in a day, but I'm not impressed so far. I've opened up all ports and protocols to their hosts and still no joy. Their website implies it's a plug in and do nothing job.

22:54:09.162908 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.164499 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.182893 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.183166 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.202757 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.203910 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.222751 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.223883 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.242865 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.243886 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.262707 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.265433 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.282735 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.283813 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.302710 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.304002 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.322902 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.323122 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.342755 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.344840 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.362831 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.363099 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.382895 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.384310 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.402768 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.405886 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.422748 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.423775 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.442726 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.445048 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.462864 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.463121 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.482912 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.484296 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.502712 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.506479 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.522733 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.523870 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.542893 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.546560 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.562728 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.563871 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 48
22:54:09.582766 IP 192.168.14.91.123 > 212.183.133.181.123: NTPv4, Client, length 48
22:54:09.583871 IP 212.183.133.181.123 > 192.168.14.91.123: NTPv4, Server, length 4

.
.
.

tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth1, link-type EN10MB (Ethernet), capture size 96 bytes
22:54:32.957641 IP 192.168.14.91.4500 > 212.183.133.179.4500: isakmp-nat-keep-alive
.
.
.

root# tcpdump -nn -i eth1 ip host 192.168.14.91
22:54:38.537487 IP 192.168.14.91.4500 > 212.183.133.179.4500: NONESP-encap: isakmp: phase 2/others ? #37[]
22:54:38.651023 IP 212.183.133.179.4500 > 192.168.14.91.4500: NONESP-encap: isakmp: phase 2/others ? #37[]
22:54:42.031076 IP 192.168.14.91.4500 > 212.183.133.179.4500: UDP-encap: ESP(spi=0x1633adf1,seq=0x257), length 100
22:54:42.053769 IP 212.183.133.179.4500 > 192.168.14.91.4500: UDP-encap: ESP(spi=0xc5588a43,seq=0x1cf), length 100
22:54:44.074197 IP 192.168.14.91.4500 > 212.183.133.179.4500: UDP-encap: ESP(spi=0x1633adf1,seq=0x258), length 132
22:54:44.097949 IP 212.183.133.179.4500 > 192.168.14.91.4500: UDP-encap: ESP(spi=0xc5588a43,seq=0x1d0), length 132
22:54:45.527801 IP 212.183.133.179.4500 > 192.168.14.91.4500: UDP-encap: ESP(spi=0xc5588a43,seq=0x1d1), length 132
22:54:45.533046 IP 192.168.14.91.4500 > 212.183.133.179.4500: UDP-encap: ESP(spi=0x1633adf1,seq=0x259), length 132

So it seems to get a working-established vpn all night long but still doesn't progress to the ready state. I've received the sms that says that it's ready for use.

I don't want to use their forums because to do that automatically turns off the sending of paper billing to you as a side effect, a necessary thing for a company, and you have to call them to get paper billing re-instated. You would have thought that would have thought of a thing called "preferences", fuckers. To turn off you paper billing, required by HMRC, as an un-notified side effect of logging into their website is just plain dirty. And the support staff know it, they don't waste any time on it, they just tell you that you can call them and they'll turn it back on.

I tried to call them, but of course my phone dropped out several times and none of them called me back. Duh! I'm calling about a device that helps overcome signal problems. If, it drops out call me back, I'm sick of wading through the menu options each time.

Still doesn't work, a whole evening later. Maybe the ntp queries relate to a QOS test, but then they should tell you that it would need to burn in for a day or two. If that's the problem in any case. As I *can* establish a working VPN, I don't know what else could be the problem. No packets are being dropped.

The latest forum posting for the device is June 27, I don't know what's going on there.

Re:Where to buy? (1)

onceuponatime (821046) | about 4 years ago | (#33584374)

Actually, after leaving it communicating furiously for about 8 hours it became ready. God knows why it does that but telling customers that it will take that long could remove a lot of time wasted. Also it sends a furious spurt of ntp traffic about evey minute. Seems a little over the top.

It does work though so far.It just uses nat traversal ipsec so most routers would need no modification I think.

Re:Where to buy? (1)

gl4ss (559668) | about 4 years ago | (#33584840)

typically you buy them from your operator. so instead of beefing up the network, they could sell you a femtocell. nice, eh?

basically this article is just about a femtocell parts provider getting a foot in the door for providing parts for basestations, which isn't that shocking, considering they're already doing basestations, but calling them femtocells.

/DRAMATIC MUSIC/ (0)

Anonymous Coward | about 4 years ago | (#33574252)

In a world... with spotty 3g service...

//Shot of woman trying to call 911 while being mugged, only to have no signal...

One company is taking it's toughened up version... to the STREET.

This summer, picoChip is... FEMTOCELL.

Re:/DRAMATIC MUSIC/ (1)

sholsinger (1131365) | about 4 years ago | (#33574430)

My dreams will be haunted this evening.

Honest Question (3, Insightful)

Sonny Yatsen (603655) | about 4 years ago | (#33574270)

FTA:

“Instant messaging and Exchange are the worst offenders,” claiming that a smartphone with “always on” applications like Exchange - while doing very little - can produce the same signalling load on the network as a device making 1000 voice calls per day.

I'm not trying to be facetious, but how does a phone with Exchange produce the same amount of load on a network as a device that's constantly making voice calls? I realize that the phone will be signaling to a server to keep data synced, but how does it produce that much load?

Re:Honest Question (1, Insightful)

Anonymous Coward | about 4 years ago | (#33574444)

It's called exaggerating the truth in order to sell your product.

Re:Honest Question (1)

Ephemeriis (315124) | about 4 years ago | (#33574644)

FTA:

“Instant messaging and Exchange are the worst offenders,” claiming that a smartphone with “always on” applications like Exchange - while doing very little - can produce the same signalling load on the network as a device making 1000 voice calls per day.

I'm not trying to be facetious, but how does a phone with Exchange produce the same amount of load on a network as a device that's constantly making voice calls? I realize that the phone will be signaling to a server to keep data synced, but how does it produce that much load?

Well... Exchange is a server product... So I'd assume it's handling a fairly large volume of traffic...

Sarcasm aside, I assume they mean it's running a mail/PIM client talking to an Exchange server. Which will be chatty. There's constant updates and checking for updates and whatnot. But I honestly can't imagine the traffic is really that high volume. We're talking about, essentially, text messages. Maybe some HTML formatting... An attachment or two here and there...

Sure, maybe some folks throw a big ol' 10 GB movie on an email once in a while...

But I can't imagine that simply using an Exchange server instead of POP or IMAP would really consume that much more bandwidth.

Re:Honest Question (1)

PitaBred (632671) | about 4 years ago | (#33577040)

Dumb client that downloads all attachments automatically? I could see it.

Re:Honest Question (1)

rabbit994 (686936) | about 4 years ago | (#33578306)

ActiveSync is HTTPS traffic. However, Exchange is "chatty" because both iPhone and Android implementations don't handle "IDLE" part of it really well. Sense Mail client ignores ActiveSync notifications that individual email has changed and issue the command to list all mails in folder again. iPhones do similar shenanigans. On average, according to my Active Sync logs, iPhone 3GS on iOS 3.x connects 4x then Winmo 6.5 phone.

Also, since a data connection is still open, I imagine that means a channel is locked up with that phone despite little data being moved and channels are limited per cell tower.

Re:Honest Question (1)

AvitarX (172628) | about 4 years ago | (#33580642)

It could be because the phone calls are 13 kbps, and perhaps once connected use a static path through the network for all data.

If "Signaling Load" means non-data data (if I knew more I could probably give it a level), it could be routing each packet with as much signaling as an entire phone call, though that would quickly get beyond 1000 calls/day.

Re:Honest Question (1)

mlts (1038732) | about 4 years ago | (#33574710)

Also, is this over a 3G/3.5G with separate data and voice, or true 4G where everything gets packetized and pushed over IP? I might be able to see someone with Exchange who gets a lot of Excel spreadsheets pushed to their device having more network traffic than a voice call, but a push or IMAP IDLE notification doesn't take that much bandwidth by itself.

Re:Honest Question (3, Insightful)

kent_eh (543303) | about 4 years ago | (#33575160)

I'm not trying to be facetious, but how does a phone with Exchange produce the same amount of load on a network as a device that's constantly making voice calls? I realize that the phone will be signaling to a server to keep data synced, but how does it produce that much load?

Because signaling traffic and user traffic are handled differently.

A very rough analogy to TCP/IP:
Signaling traffic is similar to SYN, ACK, DNS, DHCP, STP, ARP, SMB and all the other stuff you see on a normal LAN that isn't user payload.
On a GSM/UMTS network, this stuff is running on a separate virtual channel from the user traffic (voice or data). Think of it like a separate VLAN which has a max bandwidth allocated to it. (by design)
Basically, the "overhead" packets clog the signaling channel, even though the traffic channel still has oodles of bandwidth available. SYN flood anyone?

Re:Honest Question (3, Informative)

tlhIngan (30335) | about 4 years ago | (#33575268)

I'm not trying to be facetious, but how does a phone with Exchange produce the same amount of load on a network as a device that's constantly making voice calls? I realize that the phone will be signaling to a server to keep data synced, but how does it produce that much load?

Quite easily, actually. It's also the reason why the iPhone is so horrible on the AT&T network.

Basically, when your phone is "attached" to the cell network, it's communicating with the base station on a control channel. Similar to ISDN control channels, it's use for call setup/termination, management and other things. To optimize for power, the mobile station "pings" the base station with presence information (basically saying "i'm here"). This keeps the power-hungry transmitter off and only turns it on for the briefest of times. The receiver is also kept off, but it consumes less power so it can be turned on more frequently to listen for network messages, perform signal analysis (is it getting weak? Does the phone need to find another tower?). This is why if you're in a marginal signal area, your phone will consume more power - the transmitter will have ot use higher power to talk to the tower, and worst case is if you're in a marginal area between cells where the phone has to be constantly doing the handoff between cells (consuming lots more transmitter time).

Now, back to the topic at hand. Making a data "call" is exactly the same way - the phone uses the control channel to set up the call (find an uplink and downlink frequency) as well as any other network parameters, like maybe where in the frame it can transmit and receive its data on. Of course, this keeps the receiver on and the transmitter has to be active, so it consumes more power than idle. So when you want to maximize endurance, you want to tear down the data connection ASAP, which requires another control message. Depending on the application, this can mean setting up and tearing down hundreds of times, which consumes valuable control channel bandwidth.

So now your phone is making hundreds of "calls" continually as it sets up and tears down the data connection, which consumes the control channel bandwidth leaving less for SMS, other call setup/teardowns, handoffs, and the like.

Most North American carriers have the problem because the control channel bandwidth is fixed. Most rest-of-world carriers don't because texting is hugely popular, and SMS ends up consuming a rather significant chunk of control channel bandwidth. So those carriers long ago upgraded to dynamic control channel sizing to ensure that there's enough spare bandwidth for calls, voice or data. Texting is only really taken off in North America the past few years, and the iPhone was really also the first phone that was extremely aggressive on power savings by practically tearing down the data connection during pauses. End result, control channel overload leading to dropped calls (hard to be handed off the target cell can't handle the handoff request), missed calls, delayed text messages, and slow data.

I'm guessing Exchange may use a protocol that allows for frequent bringups and teardowns, especially amongst the more aggressively power saving phones.

This is a problem with all the carriers, especially since iPhones and Android phones are popular. If the Verizon iPhone is as popular as everyone makes it out to be, VZ could be in for a world of hurt if they don't already have the ability to dynamically adjust control channel bandwidth. It's also why early AT&T phone bills were more like phone books - because every time the data "call" is made, it's logged for billing purposes. This could result in pages of log entries just over the course of a browsing session as the data connection is brought up and down each time.

Re:Honest Question (1)

PseudonymousBraveguy (1857734) | about 4 years ago | (#33575678)

Short answer: 3G sucks for internet access. tlhIngan below has a more detailed explanation what happens when a phone dares to use data service.

Longer answer: Mobile telcos love to control the data flow. And when they designed data for 3G, they had more a "walled garden" concept in mind (which would have all services inside the operator network.) As they tried to include "internet" in their 3G design, they tried to keep all the control they have on their voice network. The result was a mind-boggingly complex architecture (that's also responsible for the huge latency data communication had in the first years of 3G). They tried to fix and patch up some of the flaws, but still, using that fancy 3G network for simple things like "permanent TCP connection to whereever" is more complex than any innocent bystander might imagine.

Re:Honest Question (1)

petermgreen (876956) | about 4 years ago | (#33594156)

simple things like "permanent TCP connection to whereever"
One of the things that anyone who designs a protocol that uses long running TCP connections will learn either from others or from experiance is that TCP handles the case of a long running connection with little to no data flow rather badly especially once nats get involved. Connections that have been up for a long time sometimes drop out and worse the endpoints don't always notice they have dropped out for some time.

To work arround this protocols have generally added their own keepalive meachnisms to reduce the chance of connections falling over and speed up the detection of fallen connections. Of course this also means more small packets flying arround :/

Re:Honest Question (1)

alta (1263) | about 4 years ago | (#33576030)

Each time there's a voice call there's a signaling load when setting up the call. There's a little bit when moving between cells, and a little to terminate a call.

Each time a phone establishes it's tcp/ip connection similar things occure, because the phone is NOT always connected to the network. Its as-needed. Exchange/pop3/imap are all set up to check email on an interval. Each phone is different, but lets say you're phone is doing SOMETHING every minute (exchange in active sync mode can go down to a 60 second heartbeat interval, well that's the default minimum but the admin can make it less than that) that's 1440 minutes...

Now consider all the apps on your phone that are doing this in addition to mail and you can see a lot of signaling going on.

And remember that even while you're sleeping, you're phone is still doing this.

Re:Honest Question (1)

petermgreen (876956) | about 4 years ago | (#33594004)

I think the key word is "signalling load". Raw data capacity isn't the only thing that is in limited supply on most networks. Especially networks like GSM that keep the control and data channels seperate.

I could well imagine that keeping a GRPS connection up 24/7 would put far more load on the signaling systems than making circuit switched voice connections every so often.

For an analogy /.ers are likely to be familiar. Send large packets over ethernet with even with consumer grade hardware you can max out fast ethernet quite easily and with half decent gear you can max out gigabit ethernet.

But start pushing lots of tiny packets and you can easilly get into a situation where the limit is not the maximum rate of the line but how fast the routers, switches and network cards can deal with packets.

This is neither new nor going to happen soon (1)

demiurg (108464) | about 4 years ago | (#33574450)

This is neither new nor going to happen any time soon. The cellular industry is talking about femtocells for a few years already, as this is more or less the only practical way of getting good coverage with high (think LTE) throughput. The problems with femtocells are numerous and even though vendors such as picoChip would love to see femto deployments today, providers will not rush into it until they figure out how to solve these problems. Today's cellular network work that good partially thanks to careful network planning which is impossible with femtocells. And think about regulatory problems - nobody can prevent me from taking my femto Node B to a different country where it would work on a spectrum allocated to somebody else.

Re:This is neither new nor going to happen soon (1)

petermgreen (876956) | about 4 years ago | (#33594140)

nobody can prevent me from taking my femto Node B to a different country where it would work on a spectrum allocated to somebody else.
Wouldn't GPS be a trivial soloution to that problem? Just make the cell refuse to come up if it's too far from it's authorised location.

Bandwidth? (1)

CarpetShark (865376) | about 4 years ago | (#33574484)

Aren't these home signal booster things just repeaters? If so, what happens to mobile bandwidth when a lot of these repeaters are used instead of actual basestations?

Re:Bandwidth? (2, Informative)

demiurg (108464) | about 4 years ago | (#33574534)

Home Node B devices are not repeaters. They will actually increase the available bandwidth for large number of users as they will be able to transmit with higher modulation on shorter distance, i.e. they will be more spectrum efficient.

Re:Bandwidth? (1)

Sonny Yatsen (603655) | about 4 years ago | (#33574658)

Aren't these home signal booster things just repeaters? If so, what happens to mobile bandwidth when a lot of these repeaters are used instead of actual basestations?

I think an interesting followup question to that is whether all of these femtocells will increase mobile bandwidth but will decrease the bandwidth available from your internet connection overall. The ISPs are complaining already about streaming video and power-users downloading too much. Imagine if the ISPs also had to absorb a chunk of cell phone traffic as well.

Re:Bandwidth? (1)

Ephemeriis (315124) | about 4 years ago | (#33574670)

Aren't these home signal booster things just repeaters? If so, what happens to mobile bandwidth when a lot of these repeaters are used instead of actual basestations?

They are not repeaters - they do not repeat a wireless signal.

Just like a normal wireless AP picks up wireless traffic and routes it onto a wired network, these femtocells pick up cell phone traffic and route it onto the Internet.

Re:Bandwidth? (1)

grub (11606) | about 4 years ago | (#33574852)


Just like a normal wireless AP picks up wireless traffic and routes it onto a wired network, these femtocells pick up cell phone traffic and route it onto the Internet.

If I recall correctly, AT&T counts your internet-routed voice traffic on your 3G cell plan. Pretty silly if this is the case.

Re:Bandwidth? (1)

Ephemeriis (315124) | about 4 years ago | (#33575060)

Just like a normal wireless AP picks up wireless traffic and routes it onto a wired network, these femtocells pick up cell phone traffic and route it onto the Internet.

If I recall correctly, AT&T counts your internet-routed voice traffic on your 3G cell plan. Pretty silly if this is the case.

I don't know about AT&T, but Verizon does bill you normally, even if you're using a femtocell.

Spend $250 for a box to extend their wireless network for them... Let them use your electricity and bandwidth... And they still charge you like normal.

Re:Bandwidth? (1)

WhiteDragon (4556) | about 4 years ago | (#33579910)

I don't know about AT&T, but Verizon does bill you normally, even if you're using a femtocell.

With the AT&T device, they have an unlimited minutes option (that probably costs extra, but nevertheless is available), where all calls that originate on the femtocell are not charged towards your plan. Roaming to and from the femtocell works exactly the same as to normal cell towers. That means you can start a call at home, talk for hours while driving around, etc. and still not be charged for it.

Re:Bandwidth? (1)

LiENUS (207736) | about 4 years ago | (#33587252)

Roaming to and from the femtocell works exactly the same as to normal cell towers.

Roaming from the femtocell works exactly the same. You can't roam to a femtocell in the middle of a call, at least with the at&t 3g microcell you cant

Re:Bandwidth? (1)

WhiteDragon (4556) | about 4 years ago | (#33591880)

Roaming to and from the femtocell works exactly the same as to normal cell towers.

Roaming from the femtocell works exactly the same. You can't roam to a femtocell in the middle of a call, at least with the at&t 3g microcell you cant

I stand corrected

Re:Bandwidth? (1)

MogNuts (97512) | about 4 years ago | (#33575794)

As you implied, they are really just VoIP for your cell. That said, have you (or anyone else on /. for that matter) used one? How do they perform voice connection/quality-wise to traditional consumer level VoIP (read: Skype, Vonage, Google calling, etc.)?

Re:Bandwidth? (1)

petermgreen (876956) | about 4 years ago | (#33594258)

I haven't used one but I'd expect call stability to be much the same as any other VOIP. That is totally dependent on the network conditions between you and your call provider. If the network is mostly loaded with protocols that play nice and isn't loaded too heavilly voip works great. If the network is heavilly loaded with agressive protocols like bittorrent it will probablly be shit. Jitter is the enemy of things like VOIP.

As for voice quality i'd expect that to be much the same as any other cellphone. I dunno what quality settings sky/vonage/google use but I suspect it's lower compression than most mobile phones.

Re:Bandwidth? (1)

MogNuts (97512) | about 4 years ago | (#33598376)

Interesting. I hear you on the jitter. Had Vonage for a while and it was jitter 70% of the time. And that was with a dedicated hardware router. One would naturally assume the quality would be better. Funny part is that a simple software program with no dedicated hardware or optimizations--Skype--performed almost flawlessly. And I don't have conflicting protocols like Bittorrent running.

I heavily looked into VoIP. I couldn't justify the phone company saying they would charge me $40/mo for unlimited, and with all the taxes and fees it would actually come out to $75/mo. But I couldn't deal with AT&T's overuse of compression on its cellular calls. It was so difficult to understand people half the time (although I never felt I had that problem with Verizon).

Hurray for paying more to use my service (4, Insightful)

Anaxagoras (190565) | about 4 years ago | (#33574536)

So let me get this straight. I already pay at&t over 100$ a month, but I can't use my cell phone in my new apartment because I have a crappy signal (other providers are fine, but I'm locked into my contract for another year), so I can PAY them for a device to make calls over MY internet connection so they don't have to upgrade their shoddy network! bah humbug!

Note I do have at&t and have no issues at home, but this is the situation a friend of mine is going through and they want him to buy this device to use a service he's already paying for.

Re:Hurray for paying more to use my service (1)

briansco (820110) | about 4 years ago | (#33574704)

On top of that they charge to 20 bucks a month for unlimited minutes to use the service or you end up using your minutes on your plan. So you get changed for the device, and charged to use the device. All so AT&T doesn't have to fix their network. Who says the robber barons were from the late 19th century. They are here now!

Re:Hurray for paying more to use my service (1)

MachineShedFred (621896) | about 4 years ago | (#33575108)

I have the same situation in the house that I just moved into, from half way across the country. I dropped like 10 calls this weekend, so I'm planning on calling them up (from somewhere else) and bitching at them with the aim of getting one of these for free / rebated cost.

I'm sure it won't work, but I might as well try...

Re:Hurray for paying more to use my service (0)

Anonymous Coward | about 4 years ago | (#33575456)

.... so I can PAY them for a device to make calls over MY internet connection so they don't have to upgrade their shoddy network! bah humbug!

This may fit in with having prioritized network packets (loosely, network non-neutrality). I smell more fees coming down the pipeline.

Re:Hurray for paying more to use my service (1, Informative)

Anonymous Coward | about 4 years ago | (#33575908)

simply ditch the old telco's as much as possible.

about a year ago i bought an Nokia e71 (for the phone integrated sip client... most nokias have that now)....I call ported my number to callcentric (att defenitely didn't like this... they were complete dinks about it).. and i bought a PAYG Card from tmobile.

  All being said i'm a light 'mobile' user, and my total bills are around 15 a month for both VOIP and PAYG.

At home, I get unlimited incoming and 2c per min outgoing... ontop of that i have some basic GPS nav integrated into my phone for those ocassions it can be helpful.No need for network.

I hope the telecoms rot--their gouging.

Re:Hurray for paying more to use my service (0)

Anonymous Coward | about 4 years ago | (#33576498)

in china they provide them for free

Re:Hurray for paying more to use my service (1)

dnahelicase (1594971) | about 4 years ago | (#33580278)

My boss has the same issue of it not working in his house. He had called and complained several times with no resolution. Finally, he got a "Customer Service Satisfaction Survey" where he reamed ATT in every way he could. About a week later he got a letter saying he qualified for a free MicroCell.

If I were your friend, I'd go to a corporate store (not an authorized reseller), get a manager, and ask that they give him a MicroCell for free. If they don't, demand one - or the termination of his service without an ETF. The managers seem to be empowered to give them away. I went and picked up the MicroCell, and when the barcode on the letter didnt' work, the manager just came over, typed in her override code, and we skipped all of the "setup" information that I was supposed to go through.

Anyway, the MicroCell was kinda funny in that it needed two hours to setup and get it's GPS location, but for now it's working great and gives coverage over the whole house. Service is more reliable in the house than it is outside.

AT&T sells one (2, Informative)

Muad'Dave (255648) | about 4 years ago | (#33574620)

AT&T's microcell uses your broadband connection to extend their coverage and has a GPS to validate that you're using it in an 'approved area'. Also, calls don't transfer in, so you'll lose calls as you approach your house. No thanks.

From this page [att.com] :

"AT&T 3G MicroCell acts like a mini cellular tower in your home or small business environment. It connects to AT&T's network via your existing broadband Internet service (such as U-verse, DSL or cable) and is designed to support up to four simultaneous users in a home or small business setting."

Also,

"Calls transfer out, but don't transfer in. Calls seamlessly transfer from the 3G MicroCell to the strongest available AT&T cell tower signal. However, calls connected on the cell tower do not transfer to the 3G MicroCell."

Re:AT&T sells one (1)

Dan East (318230) | about 4 years ago | (#33574978)

Also, calls don't transfer in, so you'll lose calls as you approach your house. No thanks.

I can see why the carrier wouldn't want calls to be handed off from an official base station to a private station, especially if the end user has no choice or say so. There could be a slew of problems, anything from poor latency, low bandwidth, to potential eavesdropping or monitoring. The carrier would be blamed for the poor connection of a femtocell without the end user even knowing the logistics involved.

The fact is, if you don't have cell service at your house, then you aren't any worse off for those specific calls when you are already on the phone as your approach your home. Just call them back or vice versa once you're at your house. Further, there's a good chance the cellular service will not perfectly overlap your femtocell anyway, so you're going to drop the call before you're in range of your house. Especially if it is a rural / geographical type of situation (which is very common in my area).

Re:AT&T sells one (1)

colinnwn (677715) | about 4 years ago | (#33580390)

Well, the AT&T femtocell only allows registered cellphones on it, so the issue about bad connection or eavesdropping is irrelevant. You bought it, so if your connection didn't work well with it, you probably immediately returned it. And it is your broadband service so you'd be eavesdropping on yourself. Bad connection to foreign femtocells could be an issue if AT&T allowed any cellphone to connect. But the data transferred over the broadband connection should be strongly encrypted, so eavesdropping should really never be a problem.

Re:AT&T sells one (1)

electronym (769952) | about 4 years ago | (#33580956)

Well, the AT&T femtocell only allows registered cellphones on it, so the issue about bad connection or eavesdropping is irrelevant.

It only allows AT&T registered numbers on it. It doesn't care who those numbers belong to, as long as they're with AT&T.

I have two of these devices at work and after getting them registered (using a AT&T number on our corporate account) I've been able to add any AT&T number I've tried to them, ranging from other people on the corporate account to clients or guests who were just visiting the office for one day. As long as it's an AT&T number, it will work, and it will make calls using the device.

So I'd say eavesdropping would definitely be a concern, if calls could be handed off from a normal cell tower to a micro-cell.

Re:AT&T sells one (1)

colinnwn (677715) | about 4 years ago | (#33582778)

I figured it was like the proposed magicjack femtocell, where you have to grant permission for your phone to connect to the femtocell, so a femtocell owner couldn't add your phone as an allowed device without your knowledge. If not, eavesdropping could perhaps be a concern.

But AT&T should have really configured the femtocell to require phones connecting to it set up an encrypted wireless channel, and all the backhaul from the femtocell to the AT&T network over your broadband should also be strongly encrypted with something like SSL, which would make the femtocell traffic as resistant to eavesdropping as the native network.

One known and demonstrated eavesdropping concern that most GSM network owners haven't bothered to fix yet is that a nefarious person could set up a malicious femtocell that looks like a native GSM base station, which provides only an unencrypted wireless channel, and passes the traffic on to the POTS network through Asterisk (so nothing would seem strange to the user), after copying the unencrypted voice or data stream. The GSM network isn't set up to do bidirectional authentication (only one way), and most phones are set to allow wireless unencrypted channels to provide the greatest compatibility with non-native base stations.

Re:AT&T sells one (1)

petermgreen (876956) | about 4 years ago | (#33594378)

While on the landline network someone can just climb up a pole and attach a monitoring device to your phone line. Some monitoring devices don't even require direct electrical coupling to the line. If they were smart about it I doubt anyone would notice they weren't a legitimate telecom engineer.

The fact is phones whether fixed line or mobile are not secure from either the government or a sufficiently motivated private entity. If secret information is being handled they should be treated as such.

Re:AT&T sells one (1)

colinnwn (677715) | about 4 years ago | (#33594770)

Very true. But I still think each mobile phone operator should make a best effort to secure their part of the GSM network, and that includes their carrier sold phones to require an encrypted wireless channel to the base station, and any picocells they provide to encrypt traffic over its backhaul. Doing these 2 things would make a mobile to mobile or VOIP phone call relatively secure against all but the government and really motivated private parties.

Problems (2, Interesting)

Mr_Silver (213637) | about 4 years ago | (#33574636)

The biggest problem with femtocells is that customers expect them to be free. This isn't unreasonable, after all they're paying a monthly fee to get a service and they expect that they can stand in the bathroom in their city centre flat and be able to make a call.

The problem is that building a business case for purchasing a tonne of femtocells and giving them away to customers for nothing isn't a pretty read and getting a director to sign off on such an endeavour has been tough.

They'd far rather that the money was spent solving the signal problems (which improves things for everyone, not just the femtocell owner - but at the cost of a slow resolution time) rather than publicly admit that their signal is rubbish in urban places and needs "boosting".

Re:Problems (4, Insightful)

Ephemeriis (315124) | about 4 years ago | (#33575022)

The biggest problem with femtocells is that customers expect them to be free. This isn't unreasonable, after all they're paying a monthly fee to get a service and they expect that they can stand in the bathroom in their city centre flat and be able to make a call.

It isn't so much that they aren't free... It's that they cost so much, while costing me additional resources, and not really doing much for me except allowing me to use the device that I'm supposed to be able to use anyway.

I have a Verizon cell phone. According to all their coverage maps, I should be fine. I'm not. I routinely drop calls at home. Regardless of what they say, we're right on the edge of their coverage.

Verizon offers a femtocell for $250. This femtocell will use my electricity, it will use my bandwidth, and it will not save me any money at all. I still get charged for calls and data at the normal rate even though I'm having less of an impact on their infrastructure. All I get for my money is the ability to use my cell phone in an area where they swear I should be able to use it anyway.

I wouldn't complain if the femtocell was just $50... Or if they took $5/month off my bill... Or if calls/data/whatever were discounted while using the femtocell...

Re:Problems (1)

DarthBart (640519) | about 4 years ago | (#33575472)

I wouldn't complain if the femtocell was just $50... Or if they took $5/month off my bill... Or if calls/data/whatever were discounted while using the femtocell...

I had Sprint's airave box for a while. It made for good coverage (there was a hill between the closest sprint tower and my house), but the fact that I paid extra per month just so I could have the box irked me. Then I elected to pay even more per month for the "completely unlimited airtime" option when placing calls through the airave box.

I won't make that mistake again.

Re:Problems (1)

Havok3114 (969677) | about 4 years ago | (#33576280)

I wouldn't complain if the femtocell was just $50... Or if they took $5/month off my bill... Or if calls/data/whatever were discounted while using the femtocell...

I had Sprint's airave box for a while. It made for good coverage (there was a hill between the closest sprint tower and my house), but the fact that I paid extra per month just so I could have the box irked me. Then I elected to pay even more per month for the "completely unlimited airtime" option when placing calls through the airave box.

I won't make that mistake again.

Then you didn't compain enough to Sprint Customer Service. I didn't have coverage in my house and was bringing 4 lines from a competing network. I got the AirRave free, waved activation fee, and waved monthly fee for the life of my contract.

Re:Problems (2, Interesting)

TheRaven64 (641858) | about 4 years ago | (#33575670)

That depends, of course, on who is deploying them. An existing ISP, for example, could deploy a cellular network pretty much instantly by providing the femtocells to their customers and buying capacity on an existing network.

A good candidate for doing that here in the UK would be Virgin Mobile, a virtual operator owned by Virgin Media, the largest ISP in the UK. If Virgin Media provided cable modems with built-in femtocells, they'd reduce their operating costs, because most calls in urban areas would be made within range of one of their cells, rather than having to use the Everything Everywhere network, but they could still fall back onto the EE network when out of range. They could encourage their customers to leave them turned on by paying them when a call was made through it (effectively also giving you cheaper calls when in your house).

My phone has WiFi, so I make calls via SIP when I am at home, using their network for the bandwidth but someone else for the POTS bridging. If they provided femtocells and a sane price structure, I'd be tempted to switch.

Re:Problems (1)

Mr_Silver (213637) | about 4 years ago | (#33577066)

That's a rather good idea, I like it. Would also work for companies like O2 and Orange who also provide broadband.

Unfortunately it's been a while since I received quotes from femtocell manufacturers and back then they weren't cheap. Plus the people making the routers didn't have the experience to build such capability in.

But even so ... it's a nice idea.

Re:Problems (1)

TheRaven64 (641858) | about 4 years ago | (#33587404)

If AT&T can provide them for $99, they can't cost much more than that wholesale. A few companies offer femtocell SoCs, so router manufacturers can just connect them up to power, an antenna, and Ethernet, in the same way that they do with 802.11 chips. Given the quantity of that a company like VM buys, I think they could probably say 'we want a small box that does 802.11n, Ethernet, DOCSIS3, HSPA and GSM' and have several companies offering to produce them.

This whole thing becomes a lot easier with 4G, which specifies an all-IP network. With Mobile IPv6, you can hand-off between access points, using IPSec to update the routing tables, at the IP layer. This means that a phone can move between LTE and 802.11, without dropping the call. At least, it can if the mobile phone company permits it. Unfortunately, for this to work properly they'd need to update their billing so that POTS brigding and data transfer are billed separately.

Re:Problems (1)

jandrese (485) | about 4 years ago | (#33576104)

It's not even that the hardware isn't free (like it should be), but when you're using it you're using up your own power and bandwidth (after you already shelled out $100 for the hardware), and the companies still charge your minutes when you're using it.

What's wrong with this picture? (1)

Animats (122034) | about 4 years ago | (#33574876)

Why should I pay money for a device which uses my power and my DSL connection to relay my calls, and then let the cellular carrier charge me for the "airtime"? Especially since there are WiFi alternatives?

Re:What's wrong with this picture? (1)

ceejayoz (567949) | about 4 years ago | (#33575092)

That's not what this article is talking about. The cell phone carriers are just putting small mini-towers on lots of telephone poles instead of putting in massive towers. Less regulatory hassle, less NIMBY, and more targeted coverage.

OpenBTS? (1)

Doc Ruby (173196) | about 4 years ago | (#33575208)

Can't we get this ourselves right now with OpenBTS [wikipedia.org] ? Is anyone selling a cheap ($100-200) HW unit with all the OpenBTS installed and ready to connect to an Internet VOIP/PSTN gateway?

Re:OpenBTS? (1)

DarthBart (640519) | about 4 years ago | (#33575534)

It's not just a "Can I build it?" problem. In the US, you have to be properly licensed to transmit. The micro/femtocells the carriers are releasing are covered under their FCC license & authorization. If you built an OpenBTS box and wanted to use it at home, you'd have to obtain an FCC license for the transmitter. You'd also have to coordinate frequency plans with the other carriers operating in your area.

Read about the fun the guys at Burning Man went through to set theirs up.

http://openbts.sourceforge.net/FieldTest/ [sourceforge.net]

Re:OpenBTS? (1)

TheRaven64 (641858) | about 4 years ago | (#33575708)

Not if you care about little things like legality. Using OpenBTS requires a license for the spectrum. Network operators and anyone who bought a license for the relevant spectrum can deploy OpenBTS. Individuals can not (unless they get an exemption for a test network, as Burning Man did, or unless they are in some unregulated area, like the middle of the ocean).

Re:OpenBTS? (0)

Anonymous Coward | about 4 years ago | (#33577734)

So spend the $250 the Verizon device costs, and if you have "just enough service for the phone to ring but you can't answer it" get a Wilson Electronics cell phone repeater. They make small one room devices that look like a wifi AP, and also ones that will blanket your whole house. The nice thing about the whole house is you can attach an external antenna (IE> put a more sensitive antenna outside where you'll get better signal). I don't think there was a limit on how many phones could use the repeater, and they also make versions you can use in your car. IIRC they transmit at 1 watt or 3 watt, I can't remember which exactly.

Re:OpenBTS? (1)

petermgreen (876956) | about 4 years ago | (#33594472)

I've noticed that there seems to be sufficiant overlap between the E-GSM-900 band and the 902–928 MHz ISM band in the US that you should be able to get some uplink and some downlink channels within the ISM band.

Anyone have any thoughts on the legality of doing this if the power was kept low enough?

Forget This; Get Rid of Cell Providers Completely (1)

MogNuts (97512) | about 4 years ago | (#33575600)

The way I look at it, if cell service isn't provided to your area or it's that crappy, either get a different provider or don't give them any money at all. Get Skype or some other VoIP provider (or now use Google VoIP unlimited for free) and then lower your cell to its lowest number of minutes. The difference between basic minutes and unlimited is like $30/mo. And a femtocell is just VoIP.

Why pay $100 on top of your monthly bill to get service, when you can just not pay extra and actually pay less?

Fp tr0ll (-1, Flamebait)

Anonymous Coward | about 4 years ago | (#33575894)

However I don't as it is l1Censed

Free for sprint (0)

Anonymous Coward | about 4 years ago | (#33576234)

If you call Sprint cus. support and explain that you have bad service in your home, they'll send you a femtocell for free and wave all charges.

Also, Micro > femto. Microcells are large enough to cover a large campus (like a school or office campus).

Mobile networks will be obsolete soon? (1)

ickleberry (864871) | about 4 years ago | (#33576582)

If such a device is available it will only be a matter of time before someone makes a network using only these type of devices and perhaps slightly more powerful ones with an outdoor antenna. Its already possible to set up your own GSM network using a USRP and route the calls over SIP.

Give it a few more years and they will have femtocells for 4G. The only 'mobile operator' that will be necessary is some guy with a server to do the accounting (which femtocell gets the most traffic and allocate credits from its users to the owner) and an ordinary SIP/XMPP server. Maybe people won't even bother with such trivial issues as tracking down bandwidth usage as broadband quality improves. then we can just think of femtocells as a sort of long-range open wifi system.

Where no coverage is available satellite would act as a backup, transceivers for this are also much smaller and cheaper than they were a few short years ago. The only thing holding it back is the governments who are as usual very slow to react to change and keen on their lucrative mobile network licensing deals. I have been using SIP over open Wifi networks since '06 with Nokia E-series phones and the only real problem is the range. the rest is just a few small software issues

c0m (-1, Offtopic)

Anonymous Coward | about 4 years ago | (#33576934)

it .ha5 to be fun
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