The Rough Road to Improved Wireless Communications
Compiled by the
Consulting Services Team
April 11, 2006
On Tuesday, April 4th, I attended a WiFi Mobility Conference as part of the CTIA show in Las
Vegas. While the conference was called WiFi Mobility, the real issues and opportunities extend
beyond the WiFi standards to include WiMax and other wireless standards. Nonetheless, WiFi
mobility refers to the ability to use one phone to place a call regardless of whether it is using the
cellular carrier’s network, your home WiFi network, a city wide wireless network, or any other
compatible wireless network. The reason this is important is because you are living at the time
when two “wireless” industries are about to collide. Wireless is no longer just cellular voice and
data services for those of us in telecommunications, and wireless is no longer just wireless
networking to those of us in information technology. Regardless of the industry you are in,
wireless will soon encompass features and capabilities of both industries.
The new wireless has several parts with several different names and acronyms. Here are the
VoIP or Voice over Internet Protocol refers to any time voice is transmitted over the
mVoIP or mobile Voice over Internet Protocol is when the traditional VoIP call is
handled with a mobile connection.
wVoIP or wireless Voice over Internet Protocol refers to traditional VoIP calls handled
over a wireless connection. There is no real distinction between mVoIP and wVoIP.
UMA or Unlicensed Mobile Access refers to using VoIP over unlicensed wireless
frequencies such as 2.4 GHz (used by 802.11b and 802.11g) and 5 GHz (used by
WMC or Wireless (or WiFi) Mobile Convergence addresses the handsets and systems
that facilitate voice “roaming” between WiFi and cellular networks. Where UMA refers
to all unlicensed wireless networks, WMC refers specifically to the WiFi standards
IMS or IP Multimedia Subsystem is the underlying infrastructure that allows any Internet
Protocol network to handle multiple types of multimedia content.
W-LAN or Wireless Local Area Network is a common name for a network that uses
wireless connections to link computers and other network resources, including the
internet, within a home, office or business campus.
W-WAN or Wireless Wide Area Network is really the computer industries term for
computers connected to a network over a cellular carrier’s data network.
Now I will try to use these in context with current examples:
Vonage provides VoIP service by connecting your home phones to your internet
connection. Skype also provides VoIP service, but it uses your computer as the “phone.”
If your computer is connected to the internet using a home WiFi network, then your
Skype call is being carried from the computer to the internet over your W-LAN.
Research in Motion markets the BlackBerry 7270 which does VoIP over 802.llb WiFi.
Because the 7270 uses a wireless connection (WiFi) to carry the call to the internet, and
because you can move the 7270 from room to room without losing a connection to the
network, it then becomes a wVoIP or mVoIP call. This same BlackBerry call is using
UMA since WiFi uses unlicensed spectrum. Most companies, however, will limit the
definition of UMA to using a cellular capable phone to make a VoIP call over WiFi. The
7270 does not support cellular calls, so some people will not consider it a true UMA
A notebook computer connected to a company’s network over the internet is part of the
company’s WAN. If the same notebook is connected to the company’s network over the
internet, over a cellular data connection, it then becomes part of the company’s W-WAN.
All of these examples are available and work today. The two acronyms that are just over
the horizon are WMC and IMS. When a cellular phone is capable of connecting a call
over a WiFi or cellular network, that convergence of technologies in one device is called
WMC. IMS refers to some of the infrastructure that the cellular and other wireless
companies can use to treat calls and multimedia applications similarly. IMS is only a
base component that will help improve how the rest of these services work.
Why do individuals and businesses want WiFi mobility? Here are some of the reasons.
• Decreased or at least flat rate (predictable), long distance charges.
• Ability to provide employees with mobility at work, without having to pay for their
• Better in-building coverage.
WiFi mobility has the potential to deliver on all of those promises. In fact it should answer those
needs right out of the gate. As with any horse race though, it takes a few lengths for the horse to
get up to speed. The same will be true for WiFi mobility. It’s obvious that there is a lot of hype
about all the miracles that these technologies will be able to perform. My primary goal at CTIA
this year was to find the truth within the hype. I found out that “the truth is rarely pure and never
simple.” O.K., so Oscar Wilde must have been at the show too. What I found was two very
distinctly different “truths”.
I encountered the first truth at the WiFi Mobility Conference I attended on Tuesday. The panels
at this conference generally consisted of technical executives with infrastructure companies like
Cisco, Nortel and Level 3 Communications. These are the folks behind the technologies. The
consensus was that the technology is not ready for prime time. There are two overlapping
reasons that they shared.
1. Standards – I thought “standards” were supposed to clarify technology. Unfortunately,
there are several standards for WiFi (802.11a, 802.11b, 802.11g, and many more in the
pipeline). Amongst these standards are different frequencies, different bandwidths,
different signal processing technologies, and different security protocols and
requirements. The fact that there are several standards with several different user
experiences for VoIP will keep the Unlicensed Mobile Access (UMA) experience from
being pure or simple.
2. Quality of Service – If “standards” have you confused, consider all of the non-standard
issues that will also come into play for WiFi mobility.
a. Interference – Since WiFi is unlicensed, there is no regulation or control over who
puts an access point where, or how high or low they tune the power output.
Cellular companies spend millions of dollars in time and equipment to make sure
that one cell site doesn’t interfere with another. No one is responsible to make
sure that Joe’s personal WiFi network doesn’t interfere with the coffee shop’s
“hot spot” downstairs, or with the cities “Muni-WiFi” network. WiFi is like third
world politics, anarchy rules.
b. Security – There are several security standards, but there are no standards on how
to implement them. One network may use WEP for security while the next
network down the street may use WPA, or WPA2. Yet another network may not
use any security at all. Another challenge is how to know which network uses
which security protocol and what my access rights are to that network. If you
haven’t used WiFi for data, you haven’t had the fun of being redirected to a
security page for entering your Username, Password, SSID, WEP key, and maybe
even MAC address just to log onto the web. Imagine doing all of that on a phone,
just to answer, or place, a call. Now imagine doing it every time you enter a new
c. Capacity – Even though WiFi can support 11 Mbps or 54 Mbps, depending on the
technology used, most WiFi networks don’t connect to the internet at anything
near that speed. My WiFi connection at home, using a cable connection, can
provide as much as 6 Mbps download speed, but rarely exceeds 1 Mbps
outbound. T-Mobile uses at least a T1 connection at all of its HotSpots. This
means that you start with 1.5 Mbps available for your call. But wait, there is a
woman in the corner downloading the songs she just purchased from Starbuck’s
Hear Music website, and there is a young man sipping a latte near the door
playing an online game with his buddy across the country. Add the store manager
submitting reports in the back room, and you have at least 3 other people
competing for that precious 1.5 Mbps. Divide that 1.5 Mbps by the 4 people
using it, and you are stuck trying to make a quality call on a mere 350 Kbps. Of
course that is assuming that the coffee shop has implemented quality of service
settings to ensure that the bandwidth is shared equally. To make matters worst,
some “hotspots” use connections as slow as 128 Kbps.
Here are some more “truths” from the Mobility conference:
“Seamless may be sexy, but it’s unrealistic.” According to almost everyone on the
panels, a seamless handoff between a cellular carrier and a WiFi access point makes for
good marketing, but the technology is not ready for prime time, yet.
“Hotspot voice” is very unlikely, or at least will be very unstable. The “cool factor” will
draw disproportionate attention to this. This attention will actually make the technology
seem far worse than it really will be.
SpectraLink, a manufacturer of wireless VoIP handsets for 6 years, has no plan to
manufacture a “dual mode” handset. They do not foresee a large enough market in the
near future to justify it. They also feel that corporate customers will continue to prefer
proprietary systems in order to protect the investments they made in their respective
While end-users are O.K. with unpredictable performance for a data connection, they
expect solid, predictable performance from their voice connection, regardless of the
network they are on.
CTIA Show Floor
Now that we have heard from the techies, what do the folks in Sales and Marketing say? The
truth according to every handset vendor with a converged handset is that they already have the
ability to do seamless handoffs with great sound quality. If you had only spoken with them, you
would wonder why there aren’t dozens of handsets on the market already. I’m a techie sales
guy, so I know that the truth is somewhere in between the two extremes. Does it work today in
the lab? Absolutely. Will it provide a more flexible communications option to the early
adopters? Again, absolutely. Will it be trouble free when it hits the street? Absolutely not.
Early User Experience
So let’s look at what I believe these converged phones will go through in a normal day.
6:00am (Services) Joe wakes up and turns on his phone. As his phone starts up, it
searches for networks that it can connect to. It finds the cellular network and Joe’s WiFi
network. The phone recognizes, and connects to Joe’s network because Joe programmed
his network information into the phone when he brought it home. It is early in the day, so
Joe has plenty of bandwidth on his home network to handle any calls he needs to make.
He calls his voicemail using the short code (123). His WiFi network doesn’t recognize
123 as a legitimate dialing string, so the call is rejected. You see, Joe’s phone doesn’t
look like one of the carrier’s phones when it isn’t on the carrier’s network. This means
that voicemail (123), customer care (611), and even services like #MIN* won’t work
when the phone is attached to another network. In order to get his voicemail, Joe will
need to dial into the voicemail service the same way he can from a land line phone, or he
will have to switch his phone over to the cellular carrier’s network before trying to
retrieve his voicemail. Joe decides to call the 10 digit voicemail access number and then
enter his 10 digit phone number to access his voicemail from his WiFi connection. The
rest of Joe’s calls from home work fine. He gets the benefits of cheap flat rate calling in
the U.S. and abroad. He also knows that he will have great coverage because it is his
own network. If he needs better coverage in another room of his apartment, he can move
his wireless router (the WiFi equivalent of a cell site) to another part of the apartment.
7:00am (Capacity) Joe gets into his car and begins his drive to work. Joe stops by his
favorite coffee shop and buys a large hot chocolate for the rest of his drive into work. As
Joe walked into the shop, his phone tried to negotiate a connection with the shop’s WiFi
network. The phone and the shop’s network both work with the same technology, and
the coffee shop has no security on its network so that all of its customers can take
advantage of the service. Joe’s phone connects to the shop’s network. While Joe is
waiting in line, he returns one of the voicemails he retrieved earlier in the day. Joe’s
connection is choppy. While there is no one sitting in the shop, the person in front of him
is downloading a song to his PDA phone, and the tenant in the apartment upstairs is
watching his favorite Japanese anime cartoons streaming over the coffee shop’s network.
There just isn’t enough bandwidth for Joe’s call to sound good. Joe gets his hot
chocolate and heads outside to get onto his cellular carrier’s network so that the call will
clear up. If the coffee shop had a bigger connection to the internet, or there wasn’t as
much demand on the wireless network, Joe’s call probably would have sounded fine.
The capacity of the wireless network will be a variable with most hotspots. As more and
more people begin to use “hotspots” for voice and data, coffee shops, bookstores, and the
like will find it important and valuable to upgrade their internet connections to give their
patrons a good wireless experience.
8:00am (Security) Joe arrives at work with a whipped cream mustache and a sugar buzz
from his Cocoa Grande. Joe’s IT group has configured his phone to be his desk phone
when he is in the office. This means that Joe’s phone now handles his cellular phone
number and his desk phone number at the same time. Whether I call Joe’s cell phone or
desk phone, when he is in the office, he only has one phone to worry about. Today,
however, his phone is not able to attach to the wireless network at his office. Over the
weekend the IT administrator changed the network passwords. It seems that someone
had posted the network’s security settings on a gaming website and there was a caravan
of cars sitting in the parking lot on Saturday night. Once the passwords were changed,
the caravan moved on. Since Joe’s phone can’t connect to the company’s network, all of
his calls for the day are carried over the cellular carrier’s network. That normally
wouldn’t be a big deal except that today he was finalizing the details of a contract with
their partner in Denmark. Joe will not find out about this issue until he receives his
exorbitantly expensive cellular bill in 3 weeks. Converged phones will have some sort of
“roaming” indicator, just as they did in the old analog / digital days. Just like then
though, it is up to the person with the phone to know which network they are on before
they place or answer a call.
12:00pm (Roaming) With his cocoa buzz wearing off, Joe heads out for some lunch.
There is a new restaurant down the street that not only has a great BLT, but also has a
hotspot from another cellular provider. Joe sits down with his sandwich and his phone
and tries to connect the phone to the WiFi network. The phone fails to connect due to
“security issues”. Because Joe’s phone is from another carrier, the carrier who hosts this
hotspot will not allow Joe’s phone to connect unless he pays $50 a month to use the
service. He laments that the BLT was the best he has ever had, but another one just isn’t
worth an extra $50 a month. He finishes his pickle and walks back to the office.
6:00pm (Interference) Back at home, Joe’s phone connects to his WiFi network. Joe
picks up the phone and calls his parents to make plans for the weekend. His dad answers
the call, or is it his mom, he can’t tell because there is too much static on the line. They
try to talk, but the quality is just so bad, that they hang up and try again, and try again,
and try again. Finally, Joe switches his phone over to his cellular carrier and completes
his call home. His phone has worked fine for months. This is the first time he has had
this problem. Obviously something is wrong with his wireless network, but who does he
call for support? His cellular provider made it very clear that they don’t support personal
WiFi networks. They did tell him about a bookstore half a mile away where he could
make the call on their hotspot. He tried to call the manufacturer of his WiFi equipment,
but they couldn’t understand why he was calling them about his cellular phone. His cable
provider was also no help. They told him that they partnered with a different carrier, and
that if he switched service, they would be happy to help him. Later that night, Joe meets
his new neighbors when they tell him that HIS WiFi network is interfering with THEIR
WiFi mobility is definitely going to be a benefit for many people. Like any new technology
though, it will be a slow, and probably bumpy, start. The key to our success through this
transition is to set realistic expectations with our customers and our partners. There will be
people who will see immediate benefits from convergence. There will be early adopters who are
willing to suffer through some of the hassles to have the features and benefits of these new
technologies. Just like wine, technology improves with age. Eventually the technology will
improve to the point that the customer doesn’t know, and more importantly, doesn’t need to
know, what kind of network is carrying the call. Like his home phone today, pick it up, dial,
talk, it will be that easy.