Tuesday, March 13, 2007
But, consider another situation.
You're at a conference with three hundred strangers, and you're anxiously checking your watch, waiting for the speaker to announce the morning break so you can call your office to check your messages.
Finally, the speaker says "It's 10:30. Let's take a coffee break and reconvene in fifteen minutes."
You follow the rush of people out into the hotel lobby, and you quickly whip out your phone, only to see a message flash across its cellular screen: Denial of Service.
It seems that you weren't the only one wanting to make a call. A number of other attendees were trying to do the same thing, resulting in hundreds of cellular phone calls trying to be placed from the same location, all at the same time. This spike in useage overloads the local wireless network, causing it to crash--hence the Denial of Service beacon you see flashing on your phone's display.
That's how, in the end, coffee can be bad for cell phones.
However, it is exactly this type of situation that prompted the need for smaller cellular base stations--picocells, as they're called--to serve busy areas of population clusters like hotel conference rooms. They are also used in airport concourses. Early airport installations began in 2000 in high-tech locales like Seattle, Austin and Dallas. Today, about 100 North American airports have wireless coverage. Back during the dot-com boom, Nokia installed Wi-Fi (wireless Internet) service to airports from Ottawa to Vancouver and Denver without having a permanent operator in place to handle the actual service.
Cellular technology is converging to a point in the not-too-far-off future where our wireless calls will switch between the outside CDMA or GSM cellular network to an in-building VoIP (voice over the Internet Protocol, like Skype or Vonage) network seamlessly. In fact, there are phones on the market now with WiFi capability. T-Mobile's new phone called the Dash comes equipped with WiFi, enabling it to connect to any of T-Mobile's 7,836 hot spots around the country.
In the future, there will be more convergence, as more services are added to cell phones, eventually reaching a point (probably around 2025) when wireless connectivity will seem mundane. We will be able to wirelessly communicate, share, chat, and download pretty much whenever and wherever we want.
But in the meantime, the clock is ticking on your coffee break, and you've got business to attend to. You walk out to the street, and notice that you now have five bars, indicating a full-strength signal.
Put that coffee away. It's time to get busy.
Wednesday, March 7, 2007
Tracy Wilson, staff writer for the How Stuff Works web site has just written an excellent article describing how municipal Wi-Fi works, complete with very clear and easy-to-understand illustrations. Worth the time to check out.
Here is the link to the story.
Arthur C. Clarke once said in 1961 that "any sufficiently advanced technology is indistinguishable from magic."
I believe that is the case with wireless.
Imagine for a moment if you could go back to the time when telephones were still newfangled novelties. Imagine trying to explain to an average man on the street that, one day, we would be able to talk to anyone, anywhere in the world, whenever we wanted, at any hour of the day.
That man on the street would say, "Why, we can do that too, with this new device from Alexander Bell."
Then you tell him you'll be able to do it without wires of any kind. You'll be able to pull down conversations, data, pictures and movies out of thin air--just like that man from the past could receive radio stations from distant lands.
"Why, that's magic you're describing," that historical man might say.
And yet, this is the technological world we take for granted now.
We can use cell phones and PDAs to retrieve all sorts of information, even settle debates over arcane trivia (Who was JFK's running mate? or What was the first wild-card team to win the Super Bowl?) with a couple of quick thumb-taps on a BlackBerry.
Our cell phones have evolved into so much more than mere communication devices. They are alarm clocks, music players, and digital wallets. They are road maps and talking museum guides. They help us monitor our children, our weight, our appointments, and our goals. In short, cell phones have become a remote-control for our lives, electronic Swiss Army knives that are as indispensable as our driver's licenses.
In short, we are using and sending more information through the air every day, and wireless carriers are trying to keep up with our increasing thirst for wireless knowledge.
Over the past few years, there has been an ongoing debate among some in the wireless industry as to which communication standard (CDMA or GSM) would emerge as the new global default. In the end, this debate is about the same as deciding which Dixie cup to use for a Big Gulp-sized thirst--neither one can handle the expected growth.
We can split up cell sites into smaller and smaller units to ease the load on our overburdened wireless networks, but that will only work for so long. Eventually, a new standard will have to take hold (WiMax, or some other parlance to be invented later) to keep up with our desire to access anything, anywhere, anytime.
This is the behind-the-scenes engineering that makes technological magic possible.
In a blog posted March 7th on Outlook4Mobility.com, Andrew Seybold offers a suggestion for the rest of us--waiting for technological advances requires patience. We should not be too quick to throw out the old copper cables just because they are old; there is still a lot of life (and magic) left in those lines.
Does the fact that we will have new WiMAX, AWS and perhaps 700-MHz network operators coming to the wireless party make a difference? I'm sure it will, but it will take time. Even then, many won't understand the truism that the wireless industry understands so well: "There is not enough radio bandwidth in the world to convert all of our communications to wireless. Wired will continue to play a very important role as we move forward."
The wireless industry is a great environment in which to work. It is becoming more competitive and the rules of engagement are changing rapidly. Wireless is one of the fastest-growing industries of all times, and as it morphs into whatever is next, it's fun to be along for the ride."
It all still seems magical to me.###
Tuesday, March 6, 2007
With approximately fourteen
Small “microcell” antennas, some no larger than a pack of cards, are mounted to lightposts as a means of offering municipal wireless-broadband service. These “smart” poles would be used in a “mesh” fashion, with wireless signals passing from pole to pole until it reaches a conventional monopole or lattice tower. Then, the signal would be relayed to a transmitter with a backbone connection (fiberoptic, satellite, or cable), where it would be sent out to its final destination. Users of these “smart” poles could include residential customers, public parks, emergency service providers, or city workers. Flash memory installed inside the poles could store information on local retailers, and blueprints of buildings accessible by firefighters in the event of an emergency.
One San Jose-based company, NextG Networks, works with municipalities to build microcell networks that would fill in coverage gaps created by existing wireless networks—either because of terrain challenges or competition between carriers. NextG’s technology allows them to sublease the same microcell to more than one carrier (think T-Mobile or Sprint), through the use of a special type of software known as an operations-support service (
Instead of thinking about
Kurt Mackie, Managing Editor of Broadband Wireless Business, states that mesh networks offered by companies like NextG or EarthLink offer a greater amount of flexibility than conventional wireless networks—both in installation cost and ease of use.
Because of their small size, microcells can be enclosed inside virtually any cylindrical enclosure at a cost of less than $1,000 per pole (versus an average cost of $30,000 to $50,000 to construct a typical 30’ to 40’ tall monopole). The power requirements for these smaller wireless sites are also a fraction of their larger single-tenant cousins along highways and interchanges. In fact, a Scottish university is currently testing solar panels that could be used to power a streetlight and a Wi-Fi or Wi-Max antenna array enclosed inside.
Intel, with support from Cisco, Dell, IBM and other companies, has begun an initiative called “Digital Communities,” created to educate city leaders on ways they can use their Wi-Fi networks as a commercial service by selling access. City officials could also gain additional revenue by charging roaming fees to non-city employee visitors.
Readers interested in viewing an online presentation of a program tailored to Digital Communities (called UniFi Grid), can log onto the following link:
In another C-Net article written by Michael Singer, JupiterResearch analyst Julie Ask offers this suggestion.
“Cities can use Intel’s investments to save money, Ask said, because support services for city employees in the field can be provided more efficiently using wireless communication.” City employees can wirelessly roam to locations in other cities for free, simply by entering a pre-established username and password. This innovation would allow municipal employees to be more effective and productive, while encouraging cooperation between cities.
Cities have the potential of pulling more revenue out of their Wi-Fi networks by charging visitors an access fee. Once a city makes the initial decision to charge visitors or not, their access could be handled by a simple three-step process.
1.) The visitor would log onto the city’s Wi-Fi service as a guest
2.) The visitor would then select their home city from a dropdown menu
3.) Lastly, the visitor would enter their pre-established username (based on their home city) by means of a customized log-in screen.
Cities can also use Wi-Fi networks to issue real-time announcements (like Homeland Security bulletins) to every city resident tapped into the network. City officials can then tie in other services (like parking-meter control, traffic management, and utility-meter reading) into their Wi-Fi network to increase productivity, both for themselves, and for its citizens.
In the future, municipal Wi-Fi networks could be opened up to any mobile subscriber, simply by sending a text message to a dedicated phone line, known as an 80211 shortcode.
On the state level,
“There’s no question about it. This is a necessity,” said David C. Hollister, director of the Michigan Broadband Development Authority. “We’ve made a commitment that we would have statewide broadband coverage and make it as affordable as possible by 2007.”
In a White Paper titled “Enabling the Future of Wi-Fi Public Access” dated February 2, 2004, the WiFi Alliance cited a survey done by Boingo Wireless to highlight the vast untapped potential of Wi-Fi.
“Boingo estimates that there are as many as 2 million potential hotspot locations in the
• 212 conference centers
• 3,032 train stations
• 5,352 airports
• 53,500 hotels
• 72,720 business centers
• 202,600 gas stations
• 480,298 restaurants, bars and cafés
• 1,111,300 retail stores”
At the present time,
There are a couple of things city administrators should keep in mind when considering muni-WiFi. The first would be not to act too hastily, simply to be the first in your area to offer this technology. Most wireless resellers I spoke with strongly advise cities to do their homework before beginning negotiations.
Another important consideration is to make sure your proposed network is fast enough to be of practical use. In
The downside is that
Residential users of
Wi-Max, short for Worldwide Interoperability for Microwave Access, works similar to Wi-Fi, but on a much broader scale. A single Wi-Max tower could provide coverage over a 30-square-mile area, whereas Wi-Fi antennas have a very short broadcast range of a couple of blocks or so.
With Wi-Fi, a city would need to have several lightpoles installed just to cover a downtown zone. Under WiMax, a city could pay for one base station that would cover an entire financial district. The companies maintaining the base stations for the cities might offer unlimited access for a monthly fee, or a “pay as you go” plan that charges on a per-minute or per-hour basis.
In May of 2005,
Critics of municipal Wi-Fi, like telecom analyst Jeff Kagan, argue that cities may not be the best entities to provide such services. In an interview with Wireless Week, Kagan suggested that “the question is should a [private] company run [the network], or should the city government run it, or should the government work with companies to run it. When governments run it, things don’t normally run well.”
In a recent online article about an upcoming release of 1700-Mhz spectrum later this year, Andrew M. Seybold of Outlook 4Mobility offers another opinion for wireless development in metro areas.
“What I would like to see is a consortium of companies that come together to build a true nationwide network shared by small, medium and large resellers (like Metrofi, NextG and Earthlink) offering both voice and data services.
“There are two ways in which this could happen. The first would be for a group of companies to pool their bids for specific frequencies and obtain every license nationwide.
The other would be for the government to hold a portion of the spectrum and allow a consortium of companies to ‘rent’ it (as in
Progressing in a line from lattice towers to “fake trees” to “smart lightpoles,” the next logical step in the evolution of the cell site will not be a “site” at all, but instead will be something we can tuck in our pockets. Early versions of personal wireless servers can already be found on the shelves of Costco and electronics stores, in the form of 1.0-gigabyte flash drives, or “thumb drives” as they’re sometimes called. In an ideal environment, a personal wireless server would offer the storage capacity of a computer-network server with the flexibility of a Wi-Fi wireless modem to offer true ubiquitous computing “anywhere, anytime.”
One could describe technological innovations like OSS or microcells as hurdles laid in the path of a metaphorical runner. Each time the runner clears a hurdle, his sight is set on the next one before him. With the adoption of these new innovations in wireless communication, we (as a wireless community) have also cleared a type of hurdle—the differences between our communications standards. If that is so, what will be the next barrier in our path?
This is true from an information-sharing context as well. It might be easier to think of ourselves as a community of individuals sharing voice and multimedia files with other individuals in a series of isolated interactions. Instead, perhaps we could consider that the data we are sharing wirelessly becomes part of a “data cloud” enveloping all of us—as ubiquitous as the air we breathe. Then, we may be in a better position to study the web of relations we make in this wireless world, and we will be better able to “see” the next technological hurdle down the road.
Friday, March 2, 2007
Your cell phone’s ringing. What’s the first word you might say?
More than likely, it might be “Hello” or another cheerful one-word greeting. If you speak Spanish, you might say “Hola.”
Yet, the word Hola can also be used as a reminder of the pattern behind cell-site development. As a mnemonic tool, its letters would stand for the following.
H: High-altitude or high-elevation
O: One site
L: Low-altitude or low-elevation
A: Array of sites
With early forms of communication, height was always an advantage, since it allowed the sender to convey his message over the greatest distance. The Romans used mountaintops to post simple signs, whereas native tribes would communicate using puffs of smoke, drumbeats, or flashes of light.
Back in the 1950s, as long-distance telephonic traffic grew, AT&T (when it was still known as “Ma Bell”) used height to its advantage, by building microwave towers on remote mountaintops. These sites acted as the “backbone” for long-distance communications—until fiberoptics rendered this system obsolete in the 1970s.
The higher transmission speeds promised by fiberoptic opened the door for the first wireless-communication standard, based on analog transmission. As analog networks were introduced across the country in the 1980s and early 1990s, the HOLA pattern emerged again. Older microwave sites were converted first, to provide a new backbone. Then, carriers supplemented these high-elevation sites with monopoles at lower heights.
As call volume increases within a given cell, at some point even the tallest telecommunications tower will reach its processing limit. At that point, carriers generally have two options: increase the cell’s height (and power), or split the cell up into smaller areas served by towers or poles of lesser height.
Flashlights provide a handy means of illustrating cell-site development. If I want to illuminate the area around where I’m standing, I’d find the brightest light I could find, and put it up as high as I could reach, so that its pool of light would disperse over the greatest distance. Alternatively, I could cover the same area with smaller lights closer to the ground, arranging them so that their beams overlapped each other—leaving as few dark areas as possible. As towers reach their processing limit, smaller sites are built to handle the load.
Since its introduction in the early 1990s, digital cell sites have gotten progressively smaller. Two of the latest categories of sites to emerge have been described below.
Microcells generally consist of one to two panel antennas mounted on street signs, light standards or utility poles. In southern
Picocells represent the latest in telecom-cell development. With equipment small enough to fit inside a suitcase, and antennas the size of a deck of cards, these cells are being installed in hard-to-cover, high-volume areas like airport concourses, shopping malls, subways and tunnels.
Therefore, as population density increases, so does the density of sites. As the density of sites increases, their broadcast radius decreases, as shown below.
(Note): Although a cell site’s radius depends upon its surrounding topography and its capacity to handle calls, cell sites in rural areas generally have a radius between five and eight miles, and cell sites in urban areas typically have a radius between two and five miles.
In the U.S. alone, more than 690,000 cellphone calls are made each second—more than one billion calls per day. According to the CTIA, there are approximately 184,000 cell sites in this country struggling to process this flood of information. The demand for more bandwidth to handle the transmission of higher levels of data (from analog calls to digital calls, text messages, photos and MP3s, to DVD-quality video) puts increasing pressure on engineers to develop new communication standards to better accommodate the volume of data flying through the air.
When a new standard is introduced, the HOLA pattern repeats itself: start high to cover as broad an area as possible and then subdivide into smaller cells as call-demand increases. This is illustrated in the following chart.
Chart created by The Heath Group.
Chart created by The Heath Group.
At present, we are in a transitory state between CDMA/GSM and full-fledged adoption of WiMax. While CDMA and GSM continue to battle for the title of universal standard, in the end it may not matter. Neither protocol can keep up with our thirst for bandwidth. It's a little like arguing which Dixie cup to drink out of when you have a Big Gulp-sized thirst. The latest generations of broadband wireless, including prototypes of WiMax, may satiate this demand for now. Or, at least long enough until the next standard is developed.
The forecast for the skies over cities like Philadelphia, Portland, Chicago and San Francisco are for clouds, but not the white, fluffy kind. Cities like these are experimenting with their own data clouds—several WiFi hotspots clustered together to form a blanket, or meshed coverage across a particular neighborhood. Yet the downside (at least so far) has been that these clouds are not as all-consuming as San Francisco’s famous fog. Inevitably, hotspots are too far away or behind the wrong building to do a subscriber any good. As John Ness observes in a recent Newsweek article, “the irony of Wi-Fi convenience is that, without ubiquity, dependent users can pretty quickly become frustrated.”
Since most Wi-Fi antennas are already low to the ground (30 feet or less in most cases), the only practical remedy for seamless coverage is to broadcast from a higher elevation, and at higher speeds. At the present time, we are approaching a transition in digital communication from CDMA and GSM to the higher bandwidth and speed promised by WiMax. In terms of bandwidth, WiMax portends the ability for several users in the same area to watch DVD-quality video on the same channel at the same time.
In May of 2005, a Seattle-based company installed WiMax antennas and equipment atop the Space Needle, 605 feet above the ground. At this height, the Space Needle site will be able to transmit wireless Internet signals over a five-square-mile radius, at speeds more than sixty times faster than dial-up.
So, how high is high? Will we start installing ears on celestial bodies, as they orbit overhead? Maybe not, but other equally fanciful ideas are being considered now as possible replacements to the conventional land-based pole and dish.
One enterprising company, SpaceData, is trying to extend cell-phone coverage by installing antennas in weather balloons. According to the company, these balloons will fly at stratospheric heights, above the travel lanes of commercial aircraft. Antennas broadcasting from such a lofty height would be able to cover an area fifty miles or more across.
Yet as any little boy or girl knows, once you release a balloon’s tether, it is free—guided by wind currents until they eventually disintegrate. SpaceData hasn’t quite worked out the kinks in their design, but indicated that its balloons would be equipped with GPS, and that each balloon would be equipped with a mechanism that would jettison the cell antennas if it gets out of range; the antennas would then freefall by parachute to be retrieved later.
In a Wired Magazine article published in January of 2000, author George Johnson describes the vision of some computer scientists for a new wireless “web.”
“There will be a day, maybe as soon as 2010, when the Internet disappears, when computation and connectivity become so pervasive that you forget they are there. Today’s metaphor is the network—a vast expanse of nodes strung together with dark, gaping holes in between. But as the threads inevitably become more tightly drawn, the mesh will fill out the fabric, and then—with no voids whatsoever—into an all-pervasive presence, both powerful and unremarkable.”[i]
As each new year brings another advance in technology, it can now be said practically that we can share information anywhere, with anyone, anytime. The Internet is no longer a destination; it is an all-consuming fog of bits and bytes that we stumble through as we walk the paths of our daily routines.
If, as Johnson put it, today’s metaphor is the network, then tomorrow’s metaphor might be “data consciousness”—resulting from omnipresent access to every scrap of information. Spiritual leaders often talk about reaching a higher consciousness as they delve deeper into their devotional disciplines; we are heading towards a silicon-based consciousness, spread among the flash cards and hard drives of our phones and laptops, yet meshed together to form a shared memory.
In fact, as technology gets smaller and more sophisticated, we will increasingly turn to biological vocabulary to describe its form and function, and to frame its development within a context we can understand. Words like cells, virus, immune systems and feedback have all found digital corollaries.
It seems hard to believe that just twenty years ago, cell phones were a brick-sized novelty and letter-writing (not emails, text messages, or MySpace videos) was the preferred mode of communication. If the HOLA pattern continues to hold true, we will cycle through higher and higher pipelines of communication until there is no longer any delay whatsoever between ourselves and our information. It’s been said that information is the currency of the new economy; I believe it will become even more fundamental than that, as basic as a cup of water to a parched traveler, and as integral as the air we breathe.
[i] From “Only Connect”, written by George Johnson in Wired Magazine, Issue 8.01, January 2000. This article can be read in its entirety at http://www.wired.com/wired/archive/8.01/nets_pr.html.