May 27, 2005 4:00 AM PDT

The citywide Wi-Fi reality check

Philadelphia is venturing into the Wi-Fi frontier and liking what it sees. The big question is, will it feel the same way two years from now?

The city's experiment to blanket its 135 square miles with wireless high-speed Internet access has been hailed by supporters as one of the most innovative projects in the country. But some experts caution that significant technical and business issues must be hammered out before citywide wireless networks can become a reality.

Large cities such as Philadelphia and San Francisco see wireless broadband technology as a low-cost solution to providing broadband access to low-income residents.

"We did a radio-frequency survey and didn't find any showstoppers."
--Dianah Neff, CTO, Philadelphia

They also believe that these Wi-Fi networks can help them save millions of dollars in operational costs by providing broadband connectivity for public-safety and other agencies within city government. Many believe the networks will help boost economic development by drawing more people to the city.

Philadelphia, which plans to have its citywide Wi-Fi network up and running by summer 2006, is the poster child of the municipal wireless movement.

While several smaller cities, such as Chaska, Minn., have deployed citywide Wi-Fi, the technology has not yet been tested in large metropolitan areas. Philadelphia will be the first major city to complete its network. Other large cities, including New York and San Francisco, are also looking to build their own Wi-Fi networks.

While supporters applaud Philadelphia for its vision, some experts warn that deploying Wi-Fi in dense urban areas may not be as easy as it sounds.

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"Setting up a citywide network is definitely not as easy as putting up access points all over the place," said Doug Schremp, chief technology officer of BTS Partners, a consulting firm that designs and deploys networks. "There are some technical issues that need to be addressed, and cities really need to look at the operational and business issues that come with building and owning their own network."

Building a do-it-yourself network
The idea of municipalities providing broadband service has been catching on nationwide for the last couple of years, despite pushback from local telephone and cable providers who view city-owned broadband networks as a threat to their businesses.

Some cities are digging up streets to run fiber-optic lines directly to every home and business, which will increase broadband capacities well beyond those available from cable-modem and DSL service today. But these networks are very expensive to build, and many communities are looking at lower-cost, wireless technology instead.

While it would cost about $2,000 to $3,000 per household to run fiber, wireless can be deployed for about $20 to $25 per household. Philadelphia has about 590,000 households, according to the 2000 Census. Using that number, the city figures it will cost roughly $10 to $15 million to reach every household, according to its business plan.

Wi-Fi uses unlicensed broadcast spectrum, or airwaves, to deliver high-speed Internet access through a series of antennas positioned on telephone poles and other locations. Those antennas, in turn, are connected to the Internet. Depending on its location, each antenna can provide a coverage area with a radius of about 1,000 feet.

The spectrum crunch
Even though a wireless network can be built relatively inexpensively, experts say there are many challenges to providing reliable service.

"I know Philadelphia has said they haven't seen any problems with interference, but in Boston we see it everywhere."
--Doug Schremp, CTO, BTS Partners

One of the biggest technical issues that cities face in deploying municipal Wi-Fi is that it can suffer interference from other wireless devices trying to transmit signals in the same channel. Because wireless networks run on unregulated spectrum, many devices can interfere with transmission. For example, microwave ovens, hand-held phones, garage door openers and devices using Bluetooth applications all use the same 2.4MHz frequency used by Wi-Fi networks. What's more, thousands of computer users have installed their own Wi-Fi networks in their homes.

"The 2.4MHz spectrum is already very crowded," said Lindsay Schroth, a senior analyst at The Yankee Group. "When you have a large deployment such as Philadelphia also using that spectrum there's a lot of potential for overcrowding and interference."

Interference is a problem because it can greatly impact performance on the network by causing packets of transmission data to be dropped. The dropped packets have to be retransmitted, error rates increase and the routers that send the packets slow down their transmissions to compensate for the losses.

Cities such as Philadelphia say that they don't believe interference will be a big problem.

"We did a radio-frequency survey and didn't find any showstoppers," said Dianah Neff, chief technology officer for the city of Philadelphia. "We have 430 registered Wi-Fi

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In the interests of disclosure, it should be noted that Schremp's consulting clients include incumbents such as Verizon and Comcast
Posted by (1 comment )
Reply Link Flag
Free access vs paid
The telco's and ISP's do have a legitimate complaint if the goverments are playing a active role in providing a paid wifi service.

On the otherhand I don't have a problem with providing free access. One way to offset the costs would be to allow organizations such as socalfreenet to put up wireless access points on government property. This a good solutions local government owns a lot of property and has existing fiber as well.
Posted by rshimizu12 (98 comments )
Link Flag
reality check
Reality check, indeed.

The technological problems involved in making Philly a wireless city are, I am certain, totally beside the point.

I have lived in Philly since 1974 -- I sincerely believe that the scheme is merely a way for city council to scare Comcast (the city's cable provider) and local telecommunications providers into paying serious money to make the wireless proposal go away.

Some twenty years ago, the City government took forever to decide on what company would be the city's cable TV provider. Comcast finally won out and went on to become HUGE. Many in city and state government profitted HUGELY from stock that was liberally strewn around Council, the mayor's office and Harrisburg by Comcast in its bid for the monopoly.

That was 20 years ago -- it's been a while, and the local pols smell the possibility of another HUGE payday. Believe me, Philly city council is not a a hotbed of technological visionaries. I suspect the extent of most members' interest in hardware begins and ends with Rolex watches.
Posted by (1 comment )
Reply Link Flag
What reality check?
While there are certainly pros and cons to municipal run wi-fi systems tech problems are not one of them. If cable companies and other comm companies can hire the expertise and find the solutions so can municipalities. Anybody, including governments, can hire all the experts they need and to imply otherwise is simply shilling for the corporations.
Posted by Michael Grogan (308 comments )
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systems tech problems
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Posted by George Cole (314 comments )
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The same City is Closibg Firehouses
This is the same City that is closing Firehouses and laying off Police Officers, but we can afford to go WiFi. The same City where Millions of Dollars are owed to the Municipally owned Gas Works and Water Department, that they can't collect. The same City where the Mayor and his State Rep. Brother never paid their own Gas Bill. The same City in which those who never pay their Utility Bill, but have Computers will now be able to get it Free, because this same City will be unable to collect from them.
Posted by bigbear639 (33 comments )
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Your point being?
What is your point, exactly?
Posted by DeusExMachina (516 comments )
Link Flag
Technical accuracy, please
I believe Ms. Reardon is referring to 2.4 GHz, not MHz, and I know of no commercial garage door openers that use the 2.4 GHz frequency.

Posted by frnkblk (13 comments )
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