Earlier this month, a news item from Philadelphia received lots of attention in the US. That city's ambitious plan to make wireless broadband access available over all its 135 square miles has made lots of people sit up and take notice. While some smaller cities have moved in this direction, this is the first time that a major US city has announced plans for city-wide wireless broadband.
Over the past two years, we've written from time to time about cities that have made broadband access ubiquitous -- or at least available over large swaths of their geography -- by deploying some form of wireless broadband. Last year, in "Broadband Anywhere: The Extended Broadband Home" (http://www.broadbandhomecentral.com/report/backissues/Report0308_4.html) we summarized many of the technologies--Wi-Fi, WiMAX, 3G and a variety of proprietary approaches--being used to provide broadband services in cities. In separate articles before that, we mentioned a number of locations offering area- or city-wide broadband access, using a variety of technologies:
In more recent news,
The market opportunity for city-wide or what might be termed "medium range broadband networks" is the focus of "The Portable Internet" (http://www.itu.int/osg/spu/publications/portableinternet/Portableinternetoverview_2004.pdf), a newly published report and presentation from the ITU. Released at the Telecom Asia show in Korea, the report focuses on the "market opportunity situated between the high speeds of fixed line broadband and the high mobility of 3G."
In Philadelphia, the likely path involves placing thousands of small Wi-Fi transmitters around the city atop lampposts. The system would leverage Wi-Fi's popularity and use a wireless mesh technology. Such a technology, from Tropos Networks, is already deployed in Philadelphia's Love Park, Reading Terminal Market and anywhere on Benjamin Franklin Parkway. The city has a Web site showing the current limited deployment (http://www.wirelessphiladelphia.net/?target=wheretouse&ipaddress=). The cost of the first-phase rollout has been estimated at $10 million with annual maintenance charges of about $1.5 million. We have not seen details of the financial arrangements for supporting the network, but have read that plans call for a mix of public and private funds.
What is different about this deployment is that its impetus comes from the city government as opposed to coming from a commercial company, such as Clearwire, seeing a market opportunity. The driving force for the project, according to Dianah Neff, Philadelphia's Chief Information Officer, is to make broadband available to everyone in Philadelphia for a very low price. The thrust is that all residents, including those with low incomes, should be included.
Advocacy groups for community (free) networks have existed in many locations around the world. Generally, however, they are Wi-Fi "clouds" that cover limited districts, rather than a city which is 135 square miles. Those who have "for pay" services in the city, such as Verizon, are not enthusiastic about this model of "broadband for free" just like roads and other city infrastructure--Verizon spokesman Eric Rabe was quoted in Investor's Business Daily as saying: "No one should have to give up trash collection or police patrols for free broadband."
There is clearly a broader issue than one city or municipality here. On the one hand, cities want to serve their residents well, especially those with lower incomes. In rural areas, the argument is often that there is no service or the prices are unaffordable, and having broadband access can make or break a town's development. On the other hand, companies that have invested a great deal of money and effort to provide communications services understandably think it is unfair for ventures sponsored by public money to come in and compete with them. This issue has been playing out in the US and many other countries and is far from settled in many geographies.
Although public policy questions are complicated, technology solutions are more straight-forward. Many technologies can be used to provide city-wide broadband networks. Each has some advantages and disadvantages, which must be evaluated against the particular location, objectives and business plan associated with it. The applicable technologies include:
Wi-Fi Mesh Networks
We have written previously about many of these technology categories, but have not talked much about mesh networking with Wi-Fi. For those not familiar with it, the key attribute of a mesh network is that there is no central device that controls what happens. Instead, each node has radio communications equipment and acts as a relay point for other nodes. (The Internet is an example of another system without central control.) One advantage of mesh networks is high reliability--if one node goes down, others are available to take over. Some people question, however, whether mesh networks scale well, especially in dense urban environments. The concern is that as the number of users increases, the amount of bandwidth left for user communications -- as opposed to mesh overhead -- declines significantly. Some of today's mesh networking companies assert that their protocols are designed that the overhead does not become problematic. Since we have not measured traffic in real-world situations or seen a model of carrying capacity versus usage, we haven't been able to draw definite conclusions.
What we can note here is that since the time 802.11/Wi-Fi was first introduced, successive enhancements of the standard have enormously improved its performance. A great deal of entrepreneurial vigor is going into finding ways to improve and leverage this technology, given that it has gained such significant presence in homes, offices and laptop computers.
The other feature that separates different wireless technologies and systems is whether they work in licensed or unlicensed spectrum. Most of the low cost or free networks use the unlicensed Wi-Fi spectrum, since there is no business case to pay for buying spectrum.
Current Projects and Technologies
To show the breadth of activity in this arena, we provide a quick snapshot of some of the projects that focus on this opportunity, the technologies they use and some of the recent product or standards announcements related to them. Our goal is not to make judgments, but simply to present some possible alternatives.
Wi-Fi "Clouds" and Wi-Fi Mesh:
Wi-Fi plus mobile service
Wi-Fi plus pre-WiMax technology for backhaul
Just as this was not our first article on making broadband ubiquitous in cities, we're sure there are many more chapters yet to come.