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VoIP, WiFi and the Future of Traditional Telecom
PetiePooo writes "Those of us in the telecom industry have been watching it wither and die in the past few years. Here's why. The Register has an article about the future of mobile communications using VoIP on WiFi. From the article: "... voice over IP would gradually come to be a prime driver of mobile Internet." VoIP has been considered by many for a while now to be the future of traditional telephony. Combining VoIP and WiFi makes a compelling argument for the convergence of voice and data services over a single platform. Here's a previous slashdot discussion on industry's efforts to make this happen."
"Here's why"
How could some barely deployed technology before responsible for the destruction of an industry? What, did Verizon, Sprint, AT&T, etc al just decide to make poor business choices out of fear? I'm really at a loss on this one.
It is official -- Slashdot is now reporting that circuit switching is dying.
One more crippling bombshell crushed the already beleaguered circuit-switching community when slashdot.com community didn't care that the use of circuit switches has dropped yet again. Coming on the heels of a recent Usenet survey which plainly states that circuit switches are boring, this news serves to reinforce what we've known all along. Circuit switch use is collapsing in complete disarray, as fittingly exemplified by falling dead last in the recent Cowboy Neal polls.
You don't need to be a Kreskin to predict circuit switching's future. The hand writing is on the wall: Circuit switching faces a bleak future. In fact there won't be any future at all for circuit switching because it is dying. Things are looking very bad for circuit switching. As many of us are already aware, the circuit switch continues to lose relevence. Red ink flows like a river of blood.
Fact: Nobody cares Michael
I'm not Seth.
Having the same number follow you from your desk, to anywhere in the campus, to anywhere you can get a VPN connection (WiFi or otherwise), to home (over VPN) is just too cool and too usefull if you want to telecomute part time. Some of the marketing folks were simply blown away when I showed em that they could get calls at the airport, at the coffee shop, at home, and anywhere on the corporate campus all from the same number that they used at the desk. They had call forwarding to anyone in the VoIP system whether they were in their home office or halfway around the world, could do multiline confrencing using the power of the PBX and only need the single connection in their home office. Basically VoIP, especially with ubiquitous wireless access would change communications as much as the cellphone did. And to make corporations happy it greatly reduces the costs. If all of you branch offices already have decent internet connections then adding them into the corporate VoIP cloud just makes sense, all of those calls are already paid for in the line charges. With the cost of bandwidth on an unending downward spiral the cost of calls will basically drop to zero, it really won't make sense to meter them because the metering will cost more than the connection.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
I think WiFi not just for mobile, because in development countries WiFi become fixed access. Old PSTN are so expensive!
And VoIP is just data (yes its just data) carried by internet access.
-- There is four mistake in this sentences.
Here's what I'd like to see replace it. Forget VoIP over WiFi, you still need a carrier. Wouldn't it be great if we could have a mesh radio network, with a suitable self-discovering routing protocol, that would allow calls to be made from any handset to any other handset? Combined with decent encryption, this would put the privacy back in communications.
As someone who has, on regular occasion, the responsibility of supporting Wireless access technologies for Companies, I can state categorically that the current standards are NOT up to scratch as yet.
What do I mean? Well, for a start I have lost track of the number of times individual machines on Wireless simply 'drop out' of communication, leading to perception on the part of our customers that this isn't a reliable , responsible technology.
We have seen, in implementing Wireless, a whole host of different issues - in ideal circumstances Wireless access works well, is fast enough to be used for most internal office purposes and so on.
The problem with Wireless in any form is that it is not as tollerant of non-ideal conditions. Adverse weather conditions (especially during the summer, when static build up knocks out entire Wireless networks on a regular basis), passing vehicles, other communication devices (especially mobile phones, which regardless of advancements in tech will continue to operate alongside any upgraded solution for some considerable time) and simple things like the type of clothing work by the person using the computer, have been known to knock a machine out of a WAN.
Solutions of phone technology over existing Cat5e UTP cable networking, such as that provided by Nortel Networks work well, with integration into existing office apps, but Wireless for Data is still, in the field, an unreliable technology. Wireless for VoIP still runs the issue of packet lossage (which on any Wireless solution i have ever seen runs at upwards of 25%), which is far more serious than equivalent signal loss for conventional mobile telecom solutions.
An infinite number of monkeys will eventually come up with the complete works of
This is the wrong band for this type of service. The 2.4 GHz ISM band is an RF garbage dump. Unlicensed users, such as WiFi, are at the bottom of the heap. Unlicensed users may not cause interference to licensed users and must accept any interference they get. In other words, if another spectrum user is wiping out WiFi coverage in a specific area, tough shit, you have to live with it. The fact that the vast majority of WiFi equipment is designed to be cheap instead of being designed to have good RF performance, just makes things worse. WiFi is not the magic cure for all ills that some would hype it as.
Mea navis aericumbens anguillis abundat
Like the speculation that Internet is dead, the one about VoIP and WIFI will deal local telecos a death blow is too premature.
No matter it's VoIP or WIFI, the data packets need the WIRES to complete their journey.
Who runs the WIRES ?
Well
Plus, don't forget that the local Telcos have the option to change with time.
Perhaps in 20 years, local Telcos may not earn as much money from their current business, they may branch out or exploit totally new territories.
But that's only my own 2 cents.
Muchas Gracias, Señor Edward Snowden !
Unfortunately the handset manufacturers do not sell to consumers, they sell to cellular telephony network operators which then pass the phones on to consumers cheaply. The network operators desperately need bandwidth hungry applications such as video telephony or "multimedia" messages. That is what the phone manufacturers care about providing right now. None of them would dare put anything on the market that takes bandwidth use away from the network operators.
It will happen in at most a few years though; unnatural market conditions tend to fix themselves unless conditions are truly exceptional or the government intervenes.
Finally! A year of moderation! Ready for 2019?
Ok, I've been hearing that Circuit Switching is dead for a few years now, but I don't see any technology mature enough to take it's place. Mind you, packet switching is great technology, it's just not mature enough to replace what we have in place. That time has not yet come.
When it comes to dial tone, whenever you pick up that phone, you expect to get it - period. We get very annoyed if connection drops or we can't hear anyone on the other end, no matter where we call. The exception to this of course is our wireless calls. It is still a relatively new technology and so we put up with it. We are willing to hang up and retry the call if we get a bad connection. Sometimes we even wait until we get in a new cell on the network, or wait until we get back to a wired phone. The technology is not that dependable yet.
Neither is packet switching. You have already begin to hear of the technology replacing circuit switching on occasion, but we are a ways off from massive replacement of traditional circuit switching. Just as it took a while for electronic switches to mature enough to replace the mechanical ones, so to will this technology have to mature. We are not talking about replacing a few PCs on a network. The Telecom industry moves quite a bit slower. Public expectation is just too great. No, you are going to except that dial tone to be there every time you pick up that phone; even while they are replacing the switch...
The problem is that it's much more expensive to engineer complex protocols that provide guaranteed qualities of service-- both in startup cost and maintenance in the long run-- than to just expand the pipes until the link utilization is low enough to make latency problems of IP disappear. It is a simple and stupid solution, there is no sexy protocol design that gets papers published, but it works well enough and is cheap.
Tsunami -- You can't bring a good wave down!
KPN, the ex-state run telco, still has a monopoly over the local loop. They have grudgingly allowed ISPs to offer ADSL over their local loops, but not without sabotaging the efforts here and there. But voice telephony is the very core of KPN's business... My ISP has for ages tried to offer telephony service in addition to ADSL. KPN has quite openly sabotaged their efforts. The competition and telco watchdogs have repeatedly warned KPN: "Allow such-and-such access to your facilities to arrange co-location or pay a $150.000 fine". They just smiled and payed the fines, until my ISP's voice telephony division went bankrupt. As a result I am still forced to pay the ripoff KPN fees for my local loop in order to have my ADSL.
Now my ISP seems to go another route: they will use VOIP over my ADSL line to offer me phone services! I'll get a box which will VOIP-enable my analog phone, and I'll be able to use the phone service from my computer as well. The best part: the telco watchdog figures that with this setup, I am no longer obliged to have a KPN phone subscription! Instead I pay my ISP, who will in turn pay a (very low) nominal fee to KPN for use of the local loop. This nominal fee is set by the telco watchdog.
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
This story doesn't have anything to do with SCO! Come on, where's today's SCO story? This isn't funny, man, I need my fix!
the parent has goatse.cx issues. follow that
link at your own risk.
-I like my women like I like my tea: green-
I work in the telecoms industry as a vendor supplying equipment to fixed line and mobile operators. As there are increasingly more and more players in this once-monopolized industry, there comes a great need for reduced costs, especially in the core and switching networks.
The number of subscribers increases everyday, and how would the telecom operators cope with the increasing need for additional bandwidth without laying more cables (which of course, increases cost)? By using existing IP network, of course!
The dot-com internet slump has left most of the urbanised areas on the planet over-wired, and underutilized. By deploying VOIP in their switching and access networks, fixed-network operators can now cater for more subscribers, and at the same time, stay competitive with lower prices.
Also, operators can then focus on their business (customer service, billing, operations) without worrying about network expansion, deployment and maintenance of the physical medium, since it's already taken care of by the IP network provider.
One further advantage that VOIP has over conventional switched networks is that IP networks can include a Quality of Service (QOS) package for each subscriber. This means that by subscribing to different QOS packages, subscribers can now have a choice between a low-cost, low (but bearable) voice quality; and high cost and quality alternatives.
VOIP could be the telecom's way into the future. I personally do not see the end of this industry so soon, as there are still lots of terrain to cover. The world is wider than we think!
I have been involved in the telecom industry for over 8 years, mostly in the call center arena, merging voice and data, and the thing I have yet to see is a good implimentation of VoIP to the desktop.
An earlier poster made the comment that "a number that follows you anywhere." This would not be a function of the pipe that delivers the call to you. WiFi as it stands now is not a good protocol for VoIP. In general IPv4 is not a good protocol for VoIP, and there Internet is VERY MUCH not a protocol for VoIP. It all has to do with the bandwidth that voice takes, and the unusually high quality that us humans need to have to feel the service is good.
If you want a good VoIP solution, you have to run a seperate pipe to the desktop, on seperate routers to ensure decent bandwidth. You have to use propriety IPv4 QOS and you have to sratch you head a bit when it doesn't work right. Also, you Data folks tend not to understand Voice applications and you have a hard time getting pratical support from your WAN/LAN administrators.
We have heard a lot about carriers switching over VoIP. Well, what they are mostly doing, which is pratical these days, is using it for intra-Central Office traffic, which is fine and dandy when the only thing going over your Pipes is Voice. You can guaruntee the quality, know what the bandwidth usage is, etc... but this isn't much different than ATM except that it has a cool name. A lot of us forget that almost every networking technology (ATM, T1, Fiber, etc) was orginally a voice pipe before it was used on the data side.
GSM, CDMA, etc are GOOD wireless protocols that show what adaptive bitrate protocols can do, WiFi would be abosolutly horrible in its current incarnation. It is a fully cooperative very limited bandwidth protocol. Great for our data bursts, but very bad for the sustained traffic of voice. It has a VERY large overhead, plus you had the overhead of IP and you are at a pratical 3-4Mbs which then has to content with the guy down the hall dragging porn files off a remote server or someone playing Warcraft III with 20 other players. Now even 802.11g/a would be a tough bandwidth to deal with. I don't know the specifications in detail, but I doubt they have any standard QOS features.
Anyways, that is my 2-3 cents...
D.O.U.O.S.V.A.V.V.M.
The cellphone could very well be the medium in which the goals you speak of are accomplished. Already there are reports that next generation CDMA technology will be able to far surpass the 3G data transfer speeds that we see today. Imagine a 1.5M connection to your cellphone that can also be transferable to any wireless device you have(provided you have the proper equipment installed). Now imagine that you can install a wireless hub of sorts in your home that turns all of your home phone lines into wireless lines that work off of the same phone number as your cell phone. The technology is available. It's just a matter of time before the telcos start to roll this out. I admit that I don't keep up much on the GSM technology, but it looks like in the US, Sprint and Verizon made the proper network infrastructure decisions when it came to deciding between GSM and CDMA.
The existing celluar phone system has very low power requirements. I don't think we can expect any of the existing wireless lan technologies to deliver the stable connections and long battery lives of cell phones.
The real holy grail of wireless tech is not needing wifi repeaters at all. I know a guy at CMU who is working on wireless devices that communicate with base stations and each other. That way, bandwith and power are conserved by each device broadcasting over the smallest area possible. Within densely populated areas like colleges and cities this could focus as a serious competeditor to celluar service, while in more rural areas phones and computers could switch back to the more traditional celluar and wired services.
Reality is that which refuses to go away when I stop believing in it. --Phillip K. Dick (remove SPAM to email)
Having spent the last several years watching 'telecom implode', I would observe that that has largley been the result of tulip-mania style business decisions.
Those VERY few telcos that stuck to sound business decisions avoided chapter 11, and are laughing all the way to the bank!
That being said, VoIP, properly implemented, is a very strong contender going into the next 5 years, because more and more businesses are looking for a 'silver bullet' for ALL their comm needs. The carrier that hands them a magic box that serves their internet, voice, VPN and PBX needs will retain the business of the Enterprise customer, and be successful.
This hasn't really been possible until about next year, when we reach a critical mass of clue in the Enterprise world. IP PBX vendors are already starting to clean up, because, contrary to what voice only guys tell you, or data only guys tell you, IT IS AMAZINGLY EASY to get a VoIP PBX going, if you have enough bandwidth (and most anyone can afford enough bandwidth in their office), and it is SLIGHTLY LESS EASY to get it delivered through a smart carrier, who will bring you a multi-megabit facility to handle your voice and data needs...
Bottleneck removed, Class of Service (via MPLS) built in, works seemlessly...
The key, as always, is access and bandwidth.
No idea what kind of "catches" there are, but sounds good.
This is my digital signature. 10011011001
A case in point - a friend of mone who works as a US defence contractor told me that they piloted some real fancy GPS + communication device. The only flaw was the battery life - the device wasn't so useful to mreit carrying around a charging backapck..
When I'm out shopping for a mobile device, battery life usually is among the top two crieteria..
IPv6 support QOS.
Telephony might just be where you see IPv6 being deployed first.
Telephony is by definition peer-to-peer so you are stuck if you are hidden behind a NAT. Even if you confined VoIP to a class A network like 10.255.255.255 you would only have a little more than 16 million available numbers.
IPv6 is also prepared for QOS which will be a good thing for telephony.
My experiences has been poor when routing VOIP across Internet links.
The problem isn't bandwidth/speed at either end - but throttling at the internap points between backbone providers (XO Communications is particularly notorious when it comes to this issue)
When it comes to VOIP packets, there needs to be decent QOS/Priority Queuing from end to end to make it viable - and right now the tier one providers aren't exactly playing nicely together in the sandbox.
---- "Logoff! That cookie shit makes me nervous!" - A. Soprano
Sure, for a few Customers WiFi be able to handle some Traffic, but let's look at the bigger picture.
When you have thoasands, or even millions of Customers trying to make calls, how is WiFi going to deal with that ?
Where are all these WiFi Base Stations going to be ? Who's going to pay for them and the connections needed (DS1, DS3, Cable etc.) ? How many of these are we going to have to have to provide adequate coverage ? I mean, why should I open up my Network so John Doe can use my Bandwith ? Why am I paying for his use of my resources ?
How about Frequency planning and co-ordination ? We have problems now with Frequency re-use in large Markets, and that's with upwards 30 Mhz of Bandwith !
No, right now I agree that VOIP will have it's uses, but it's going to be on the Carrier side to reduce Transport costs.
I am a maintenance tech for a local 911 call center and so far we have not had to deal with the voip mystery of where the caller really is, so I wonder if there are any others like me that have had to deal with location information issues and if you had any real troubles with programming of the voip to pstn translation so as to really find where that guy is who is choking on his latte' and needs a paramedic right now, but we can't find him cuz the ALI/MSAG database says he is in a building at X/Y location where the switch is but no closer for us to tell...
:)
We have this issue with cellphones now, I can only imagine when wireless voip becomes common that it will take quite a while (read years) for it to come up to speed for providing location information to our call centers.
And our local city has decided to convert all their phone switch/system to voip over copper (cisco I believe) and we already have had issues with location information not being correct or dynamics (phone user takes his phone to a different building but database says he is still where he was) not staying accurate.
Wonder how others are coping?
Now with that said I hope that wireless voip happens, cuz I think the idea rocks too, its just that 911/PSTN services are still in the dark ages when it comes to technology (publicly funded, means slow to change)...
Been a lurker for years now, and finally get to post on something relevant to my trade
Buddha of compassion
As a consultant to the telecom industry, I have to pay attention to what works, not what sells papers. This year's big hype is WiFi, which was designed for room-sized LANs but somehow seems to have captured the imagination of the public as if it could actually hurt the telcos (ILECs). VoIP has been hyped since '96 or so, and has eaten tons of vulture capital, and while it has nice niche applications, it is still no substitute for the Real Thing.
Yes, you can run voice over IP. Yes, you can run IP over wireless. Heck, 16 years ago I was running IP over 1200 bps Aloha AX.25 packet radio links. Very instructional, because Phil Karn's NOS let me watch a decoded protocol trace of passing packets, and they came so slowly that I could study all of them in real time. Think about it. The point is that you can't run voice over *any* IP, just some paths.
Circuit-switched telephony is cheap to build. Sure the existing telco networks are made of gear that they paid a lot for, but ILECs depreciate gear over 20+ years. So the Lucent 5ESS and Nortel DMS-100 are VAX-era hardware. What did a MIPS cost when the 5E was designed? Modern circuit switching (which CLECs and some small ILECs buy, not to mention the PBX market) uses modern parts. The switching hardware is only a little costlier than IP stuff, and it sounds better. All the sexy call control features are in the control software, which in a modern system is agnostic about physical-layer protocol. So you can do nice things on circuit, ATM, or IP. Just a different card in the switch.
WiFi's limits are obvious -- there's finite spectrum, and it's shared with domestic cookers (microwave ovens are right in the middle of its band!), cordless phones, VCR "multipliers", baby monitors, and all sorts of other crap. WiFi5 is cleaner spectrum, though the lower-volume gear is costlier. The 5 GHz band will benefit from a recent FCC rule change that adds 275 MHz more bandwidth. But unlicensed still means low power, and either very short range *or* directional antennas (which take more work). And you have to worry about things like hills and trees.
I'm always looking for alternatives to Bell wire -- that's really a big part of my job! But WiFi ain't it. There are non-WiFi radios that are better for "last mile" purposes (and slower, because they have to trade speed for range -- see Shannon). The FCC is contemplating making some additional frequencies available, and in rural/exurban areas, especially flatland, wireless can do wonders. In hilly or woody areas, it's tougher. In urban areas, spectrum is too limited. Fiber optic bandwidth is infinite -- there's lots of sand out there, and only one radio spectrum.
Thus spoke "Chief Zones Officer" at MyZones:
"Today, broadband is email; but it enables voice. That's why it's so exciting. We want to get everybody a little excited, a little bit edgy."
WTF?
I suggest he really wants to get everybody a little bit confused. Easily achieved with consumers having to listen to BS such as this.
Confusion among consumers is the key to ensuring small-print laden service contracts and complex tariff structures maximise revenues. Drive the demand with sexy marketing slogans but gouge the poor consumer with the small print.
Cynical? Maybe. But "Broadband is email" oh puh-LEASE!!
And where can I get certified to become "Chief Zones Officer"??
Backward%20compatibility%20is%20over-rated
What are the current encryption options that the available VOIP Wi-fi phones offer ?
None at all (basically only WEB but that is insecure) or are some models beginning to offer VPN capabilities ? (connecting via VPN either with the hotspot or with your remote office).
Where will the security part of VOIP Wi-fi phones head in the upcoming years ?
IPSEC ?
Does anyone know about IPSEC roaming ?
eg. you make a vpn with hotspot 1 and then move to hotspot 2 without the need of shutting down and establishing the VPN connection again.
Any useful URLs ?
thanks for infos !
If you have only a mesh of six or two T1s, then sure, maybe replacing all those T1s with pairs of T1s or fractional T3s and replacing all the routers with new ones to handle the new bandwidth might be cheaper than playing around with complex protocol design.
But if you have a nation wide network with literally hundreds of network links and hundreds of routers, just 'expanding the pipes' becomes a nightmare operations issue.
Consider the phrase "compound interest". With a small amount, in the short term, it's not that impressive. With a large amount, in the long term, it can yield some pretty impressive returns. Just "expanding the pipe" is the same thing -- works fine in the short term, on small networks. Over the long term, it gets exponentially more cost-complex.
(It should be noted that the human race is running around building such things as the Internet precisely because it didn't "add more muscle" or "add more speed" or "add more armor", but because it figured out how to use what it had more intelligently than its competitors. At some point you have to start using your brain.)
There's a good argument for voice over IP on fibre, because transmission there is cheap and there's a fibre glut. But deploying 3G telephony to provide faster Internet connections so that VoIP can be run over them is stupid.
Besides, cellular minutes are so cheap now...
Call my New York Telephone number and it rings wherever in the world I've got the ATA connected. It has worked in Tokyo and London with better than cellular voice quality.
I don't have the same mobility as cellular and I have to register the phone with the server everytime I relocate it, but it's a push of a button.
And for $39.95 a month I have unlimited calling within the US (inc. Alaska and Hawaii) and Canada... and real time access to my account, voice mail I can access through my PC anywhere in the world. While the price isn't going down yet, the scope of coverage is. Canada was recently added without any increase in price.
My local Bell can't match this and isn't even trying. In fact, if you have access to cable, you don't even need to be connected to the local loop.
Local telephone service IS dead. It just doesn't know it yet.
FYI The best reference on Internet Telephony is:
Harte, Lawrence 2003: Internet Telephone, How to Select, Setup, Use, and Optimize Telephone Service through the Internet. Althos.
Until they start putting authentication at Layer 2 in WiFi, this is a really dumb idea. Given that 802.11 control messages are unauthenticated, it's going to be really neat to actually be able to DoS people's cell phones. The next time some idiot talking on the phone while driving nearly runs you off the road, you can literally cut off his phone. The same in movie theaters. Maybe this isn't such a bad idea after all.
All it takes is sending WiFi deauth control messages to the broadcast MAC and your phone won't be able to associate with the network, nor will any WiFi device in the vicinity. There's already code that exists to do this now on Linux for 802.11b, and it wouldn't take much for someone to write code on their own to do it with libradiate.
WiFi would be great technology, if the IEEE hadn't been boneheaded about securing layer 2.
Yes, the industry is converting to VoIP. However, most of this trafic will occur over fiber, with WiFi being one possibility for the "last mile". The telecom industry is also responsible for fiber. They are doing poorly because they spent a lot of money laying fiber, and there isn't currently as much demand for broadband as anticipated. Switching to WiFi from cellular won't hurt the telecom industry since by definition you're a telecom player for both systems.
Vote for Pedro
That spectrum is shared as you say. So if I have the legal right as a licensed service to run a 200 times the rf output power you legaly can your nice kit will not work. I don't know if this is a real problem at 5 gigs but you get the picture. Spectrum is limited fiber is better. How comfortable are you with a 5 gig signal at eye/brain level anyhow?
Heheh 1200 baud AX.25 Packet is still active. I know WHY but it's handy and free that little yellow light is flashing on my TNC now even. Look Maw! Email!
As you can see I don't care about my karma.
VoIP predictions like these reminds me of all the media buzz about SMDS data services a few years ago. Lot's of hype, yet very weak market acceptance. Where's the value proposition for a traditional carrier with a huge sunk investment in circuit switching infrastructure (i.e. most of the incumbents)? The majority of VoIP solutions to date just haven't had a viable business model. So, what's changed? It would appear, nothing. Another case in point, more than a decade ago industry analysts predicted that ISDN BRI would quickly displace analogue phone lines, and that the modem industry would die a quick death. Needless to say, it didn't happen. In fact, all preceeding telecom network technology appears to have experienced a useful life that's longer than most people ever imagined (ironically, with the exception of SMDS). Telecom service ubiquity is dead. Long live service coexistance.
When moving around with your traditional cell phone, you move from one cell to another. The handset and network both switch "connections" simultaneously. One analogy is to think of the cell phone as having a really long imaginary phone cord (or ethernet cable for VoIP) connected to a wall jack. As you move around, the cord stretches out so far it can stretch no more - so the magic in the system silently connects you to a "closer" wall jack in the blink of an eye.
Incredible numbers of man-hours have gone in to designing and implementing the current cellular networks so they operate with this "live mobility" -- moving around without dropping your call. And it mostly works but still not perfectly (Can you hear me now? Good).
Handoff in general is a very thorny problem, and one of the advantages the cellular carriers have is they know exactly WHERE all their base stations are and what the radio wave patterns are in the area. This is hardly something a de-centralized collection of WiFi hotspots lends itself to.
I have yet to see anyone propose a solution to the handoff question on WiFi. For "normal" IP traffic, it is okay to drop your connection and re-connect on a new WiFi node in a reactive fashion. Maybe you lose the connection for a second or two - no big deal. But in the voice cellular world handoff occurs in the order of a millisecond. Can WiFi hotspots really support this?
If one cannot handoff between WiFi cells, then immediately this is a non-starter for current cellular users. The WiFi hotspots are by definition discontiguous, so if one cannot handoff between traditional cellular and WiFi, this is also a non-starter. And it boggles the mind to imagine the coordination of all the WiFi hotspots and the cellular carriers.
Just because you can get a VoIP call in a particular WiFi hot spot does not mean you can talk and walk. As others have said, if you want phone number portability, call forwarding has been around for decades. IMHO the cellular carriers have nothing to worry about.
Anybody want a peanut?
I'm sorry, but I fail to see how the Telco's are overcharging for their services. Let's take a look at what their overheads are, shall we?
1-putting the cables into the ground. You're looking at around $500,000 for a fibre trunk between two exchanges, and there's a hell of a lot of exchanges out there.
2-wiring maintenance. Copper rusts, cables break, and this all costs money; a lot of it, and often.
3-transmission equipment. It's cheaper to buy an apartment in a prime real estate zone than it is to buy a DSLAM, and every exchange will need a few of them. And, as said earler, there's alot of exchanges.
4-continual replacement of transmission equipment to keep up with the times. Technology moves at a fast pace, so must the replacement speed of Telco equipment.
The telecommunications industry most certainly isn't the richest industry. Profit margins are 10%, if you're lucky.
If you want to knock anyone for being overpriced, talk to Mr. Gates; one does wonder where his US$40,000,000,000 in personal money did come from..
I work for the state, and there are multiple levels of bueracracy. If I moved offices, then I have to pay about $40 to another state agency come out and move the pairs to ring in another office. (Actually we move our own pairs, but for other departments that's how it works - keeps than from moving every other day.)
VoIP, you would just need to go in and tell it to have the number ring over there instead of here.
Not to mention not having to wait 2 weeks for this crap to actually get done - and the costs savings for ditching all the lines and basically becoming a PBX.
Actually saw a demo where a guy brought some VoIP stuff to a conference, plugged it into the network their and whammo - his phone was now ringing in that room, not 100 miles away back at the office. Pretty cool.
You really shouldnt do that with your mother its highly illegal and twisted.
To be honest, it's hard to say what the payoff is... yet. It's hard to make direct comparisons.
... the VoIP traffic separated from best effort traffic.)" -- instead of running two parallel networks (SS7+IP), you are now looking at running two parellel networks (IP (VoIP) + IP (data)) -- which is what is happening now with most of the carriers running a separate, private IP backbone for their voice traffic.
Keep in mind that in many, though not all, cases the 'cheaper' phone service over IP is also of less quality than the PSTN -- or less assured quality. (i.e. codec compression, lack of QoS guarantees, etc.) It's often easy to make a cheaper version of a product by lowering the standards. So, payoff for Sprint and other companies: more calls crammed into less bandwidth over trunk lines giving more efficient use of bandwidth maybe without any 'noticeable' (to most people) sound quality degredation from the extra compression.
Keep in mind that as you said, "Though to run a voice network
Insofar as expensive telco switching equipment goes... a lot of that has been paid for. The IP softswitch market just about died last year (I used to work at a company on a softswitch -- laid off because no one buying them.) When you have a *paid off* 5ESS that has a 99.999% uptime/reliability sitting in the CO quietly making you money, you don't just toss it out the window and go take out loans to buy a whole new set of VoIP gear, train people in new tech, replace everything, etc. Now, for a new phone company or a start-up or CLEC, the VoIP gear is a cheaper route to start up with. Mass replacement of old telco equipment is not likely -- a gradual migration is more likely.
Also, VoIP has a lot of regulatory hurdles left to jump, and some of them are whoppers. Probably the trickiest is a secure, reliable location service for 911 emergency calls. (Note that many countries have their own SS7 variants for call signalling, in many cases often due to local laws/regulations requiring that calls be handled in a certain way. Unless those laws are relaxed for VoIP, it is going to be quite a nuisance to implement.) (i.e. phone calls made from a prison are/can be handled differently than calls made from a pay phone or from calls made from a home phone) This isn't saying that it can't be done, or won't be done, just that at the end of the day, moving everything onto VoIP may not be as cheap as people expected (if it's cheap at all.)
Long term, it's really hard to say. Production on old-style telco gear has started to wind down, if not stopped, so the only way forward is through next-gen products. However...
IPv6 is going to suck, bandwidth utilitization wise, for VoIP calls, because VoIP data packets need to be small -- people might be looking at 30% to 50% IP header bandwidth "tax" -- that 10% ATM cell head "tax" might suddenly start to look better (because ATM was designed with voice in mind more so than data.) Seeing what happens with that will be interesting -- bandwidth may be cheap enough by the time IPv6 hits that it doesn't matter, but we'll see.
(Presonally, I can only hope SIP 2.0 dies a long overdue death and is replaced by a better excuse for a VoIP signalling protocol.)
Probably little to do at this point but kick back and see what actually survives in the real world.