January 1997 — Exclusive

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The Connected Schools of Belen, New Mexico: A Wireless Success Story

Essentially, with the T1 wireless network linking all the schools,
all workstations became part of a WAN,
using TCP/IP as the protocol.

Because the closest Point of Presence (POP) for Internet connectivity is in Albuquerque, 30 miles away, and the radios, using no more than the FCC Part 15-specified one watt, cannot reach that distance, Belen was compelled to look to their local phone company (US West) for dedicated line access to the city. The telco quoted $1,000 to $1,400 a month (or $12,000 to $16,800 a year) for a T1 link to TechNet's POP in Albuquerque. So the district started with only a 56kbps frame relay connection, using a $500 DSU/CSU, for which service costs $125 a month, or $1,500 a year. With similar quotes from the telco for local TI loop connections between the schools, comparative costs originally faced by the Belen District broke out at follows:

By using wireless, the district could get T1 links they could not afford otherwise. The projected savings compared with the only feasible alternative of telephone company-operated wired networks, was $320,000 over the first 5 years and $740,000 over 10 years. These are very substantial economies for a small district.

This capability would not exist if not for the no-license radios, for reasons of recurring cost. There would be -- according to Greg Anderson, the person most responsible for the successful network -- no more than 8 separate local-school LANs installed and possibly, a limited 56kbps wired access from each school to the Internet. There would be no cross-district LAN capability, much less the multimedia (voice, sound, animated image, and text) interactive work that full education demands, and which the wireless T1 capability now gives.

Startup Experience

Installation was done in the summer and fall of 1995. By January, 1996, the wide area, Internet- connected network was in use by teachers. For at least one month after installation, there were severe reliability problems caused by software not handling IP packets properly in the radios. These were corrected by new software by Solectek.

Another difficulty stemmed from problems with the 120-degree arc limitation of directional antennas Tamsco chose to use on the high school hub, while the three furthermost schools are in a 150-degree arc from the point of the hub. They were not able to get an omni antenna to reach the distance required. So they were forced to install two directional antennas on the high school hub's tower and relay through one school's radio -- feasible, but tricky.

When I visited the school district with Dewayne Henricks, my Co-Investigator on this NSF Wireless Field Test Project, he noted other technical solutions existed. But we both agreed that there is relatively little wireless expertise in circulation yet. Until schools and colleges and the vendors who support them learn these new fields, just as in the past they had to master microcomputers and wired local area networks, there will be many mistakes.

We felt obliged to warn them that, under current Part 15 FCC rules, they might be interfered with in both the 915MHz and 2.4GHz bands by both unlicensed and licensed devices, with no recourse. There was no particular protection for them, even though, to us, they were performing a very important public service with their radios. They were unaware of all the regulation involved, and only dimly understood the technical issues.