Dear Supervisor - September 25, 2004

September 25, 2004

Dear Supervisor,

At the September 21, 2004 Sauk County Board of Supervisors meeting, Tim Stieve mentioned the City of Philadelphia wireless Internet project. He implied that since Sauk County occupies an area 6.2 times the area of Philadelphia that a similar wireless network for all of Sauk County would cost 6.2 times more. Philadelphia is spending $10,000,000 to install and $1,500,000 annually to maintain 1,350 wireless base stations. Multiplying these figures by 6.2 would imply that Sauk County would have to spend $62,000,000 to install and $9,300,000 annually to maintain 8,370 base stations. Since I have been advocating that Sauk County should consider a county-wide, high-speed wireless Internet network as an alternative to investing $6,000,000 in extending existing technology, I would like to “do the numbers” to respond to his estimates.

It is true that the area of Sauk County (840 square miles) is 6.2 times greater than the area of Philadelphia (135 square miles): 840/135=6.2. However, I would suggest it is not a valid method to estimate the cost of a similar network for Sauk County. Each base station can handle a certain amount of network traffic. The 1,350 base stations for Philadelphia is the number designed to support network traffic based on the maximum number of concurrent users, i.e., people. So population, not area, would be a more accurate method of comparing the relative costs of a wireless network in Sauk County, The population of Philadelphia is 1,500,000 people. The population of Sauk County is about 58,000: 1,500,000 / 58,000 = 25.8. Therefore based on this method of estimation, the cost of an equivalent wireless network for Sauk County would not be 6.2 times greater, it would be 25 times less. 6.2 times more base stations (6.2 x 1,350 = 8,370) would amount to 10 base stations per square mile which would mean one base station every 1,000 feet throughout the county. Obviously this would be a gross over-estimate.

Another method of estimation of the cost of a wireless Internet network in Sauk County would be to compute how many base stations would be required to completely cover the area of the county. The IEEE 802.16 WiMax specification that we are discussing states that each base station has a theoretical maximum range of 31 miles. However, a practical range is considered to be 3 to 4 miles. If we assume a conservative estimate for effective range to be about 2 miles, then a single base station would cover a circle of radius 2 miles or an area of 12.56 square miles (3.14 x 2 x 2 = 12.56). The number of base stations for the entire county would then be 840 / 12.56 = 67 base stations. Since Philadelphia is deploying 1,350 base stations, 1,350 / 67 = 20. In other words, Sauk County would require not 6.2 times more base stations, but 20 times less base stations. This is in the same ballpark as the rough estimate above based on relative populations.

These are rough estimates. However, as another validation of these estimates we can look to a real-life example in Houston County, Georgia. Houston County is a rural county like Sauk County. Houston County’s area is 376 square miles compared to Sauk County’s 840 or 840 / 376 = 2.2 times smaller. Their population is 120,000 about twice Sauk County’s. This county is deploying a county-wide wireless 802.16 WiMax network for all its residents. Working with engineers they estimate the cost of their network to be $2,000,000. Using this example Sauk County’s wireless network cost would be 2.2 times greater or $2,000,000 x 2.2 = $4,400,000. (Note: This estimate is actually higher than necessary because I am not reducing it by half it to account for the smaller relative population of Sauk County.)

I believe the three separate estimates above show that the cost of a high-speed, wireless Internet network for Sauk County would cost less than the $6,000,000 being spent on the current project.

The county’s engineering plan that the current project is based upon was performed two years ago. The 802.16 WiMax standard was approved in January, 2003. Therefore, this alternative network technology did not exist when the county’s engineering plan was done. Therefore, before the county invests $6,000,000 in upgrading their existing older technology, it would seem to be prudent to get an up-to-date engineering report that considers using this new technology.

I believe there is still time to get an opinion from a qualified, licensed, professional communication expert with direct experience in this latest technology. It is not only prudent, but proper due diligence by the Board of Supervisors. Even if construction of the current project is continued, does it not make sense to verify that the county’s project can at least support the new wireless networks in the near future?

Respectfully,

Mark Culverhouse
Spring Green WI 53588

References

1) IEEE 802 General Information - “An amendment, 802.16a, approved in January 2003, specified non-line-of-sight extensions in the 2-11 GHz spectrum, delivering up to 70 Mbps at distances up to 31 miles. Officially called the WirelessMAN™ specification, 802.16 standards are expected to enable multimedia applications with wireless connection and, with a range of up to 30 miles, provide a viable last mile technology.”
http://www.ieee.org/portal/index.jsp?pageID=corp_level1&path=about/802std&file=index.xml&xsl=generic.xsl

2) The Associated Press – “Philly Considers Wireless Internet for All”
http://cnn.netscape.cnn.com/news/story.jsp?flok=FF-APO-1333&idq=/ff/story/0001%2F20040901%2F0654343788.htm&sc=1333

3) MoveTheTower Web Site – “The Case for a Public Wireless Network in Sauk County”
http://www.highway60.com/movethetower/case_for_wireless.htm

4) "Houston (County Georgia) could be first wireless county in U.S. Internet would be available anywhere in the county without plugging in"
Houston County - 376 square miles, $2,000,000 project. Terry Smithson, education marketing manager for Intel, said the new technology, called 802.16 or WiMax, could make Houston the first completely wireless county in the United States. Smithson said providing the service to all of Houston County would probably require two communications towers, each providing service in a 30-mile radius. Morgan Law, executive director of the Houston County Development Authority, said the service could have an important impact on the county's ability to attract and retain businesses.
http://www.macon.com/mld/macon/news/7378346.htm

Other Letters to Supervisors on Wireless Internet for Sauk County