There has been a lot of speculation on what technologies the big telcos are going to use to meet their CAF II obligations. They have a tall task in front of them trying to bring a least 10 Mbps broadband to large swaths of rural America.

I know a lot of the areas they are being asked to serve. The typical rural county has some broadband in the county seat – often from both a cable company and from the telco. Businesses in county seats can usually get as much broadband as they want if they can afford the high prices offered in these communities for real broadband.

But the cable TV networks’ service areas usually stop near the city boundaries. And DSL that originates within the county seat doesn’t carry very far into the rural areas. To make matters worse, much of rural America still has older DSL technologies that can deliver only 6 Mbps or 12 Mbps for short distances. It’s not unusual to have a few other pockets of broadband in the typical rural county – there will often be a few subdivisions or other small towns that have DSL and perhaps even cable TV.

However, the vast majority of the physical area in most rural counties is served only by long copper telephone lines, which are usually too far from a DSL hub to get any meaningful DSL. Other than those few subdivisions that have DSL hubs, there is probably little if any fiber running to rural areas. There might be long-haul fiber running through the county, but this fiber was not built to serve local customers.

The CAF II companies are facing the goal of bringing broadband to large copper-only areas that have no existing fiber. The options for technologies that can affordably bring broadband to such areas are limited.

One solution is to build a lot of DSL hubs in the rural areas to bring DSL closer to homes. One advantage of a DSL upgrade is that it uses the existing copper wires to deliver the bandwidth. But DSL on copper won’t carry the 10 Mbps speeds required by CAF II, particularly on the older and smaller gauge copper that is found in rural networks. So the DSL option requires building a lot of fiber and a whole lot of DSL cabinets. That is expensive, particularly since in many rural areas there might only be a few potential subscribers within reach of a given DSL cabinet.

The DSL solution also assumes that the telco has maintained the copper network, and we know from experience that there are many rural areas where maintenance has been neglected for decades. Making DSL work on a degraded and compromised network can be a major challenge. We also know from experience that when you try to cram too many DSL signals in small-gauge copper cables that you get cross-wire interference that degrades the speeds.

One alternative to building fiber to DSL huts would be to instead deliver the bandwidth using point-to-point microwave radios. Microwave radios have been around a long time and are reliable. But the technology requires the use of towers of some sort – something that the telcos don’t own today and that is often not very common in rural areas. Still, there are certainly many places where a microwave radio shot is going to be cheaper than building new fiber, even considering the cost of building some towers.

I have talked to a number of engineers on the topic and they think that the telcos are going to have to introduce some point-to-multipoint wireless radios into the network to reach the most remote customers. I’ve looked at maps of many of the CAF II areas and in most of these areas there are numerous pockets of the network where there might only be a half dozen farms or homes in a large service area – and there is no cheap wireline option to upgrade such sparsely populated areas.

There is one other option that I know of – the telcos might just ignore the most remote customers. Once the networks have been built and the CAF II money spent, I’m not sure what recourse the FCC has to make the telcos finish the job. We certainly have a long history of telcos that have skirted regulatory requirements or that have reneged on promises made to regulators. So I suspect that if the telcos reach some ‘reasonable’ percentage of the people that are supposed to get the CAF upgrade that the FCC will put on its blinders and call it a job well done.