This isn't a criticism of CO or Tier 2 people. It's a criticism that there's such a flawed system that most CO folks have little technical training (if any) on the outside plant infrastructure, and they are left making the call about whether to roll a truck. Their mantra is "when in doubt, dispatch out." That's a pretty darned expensive solution particularly if it's not needed.

Let me tell you more about how this all fits into a call I had yesterday with a technician whom I'll call "Greg Johnson." Now Greg took my class a while back but like many techs, he was second guessing himself because of what the CO told him and what an equipment provider told him. They were wrong and he was right. This is typically the case if the technician has been trained. Here's how the call went:

Greg: Donald, hi, this is Greg Johnson. I took your class and I have a problem I just can't resolve.

Me: OK, tell me about it.

Greg: Our company has several customers that want 3 stream video, but they are either at the end of the reach or exceed the reach and are experiencing problems. The customer has 4 TVs in the house and when he attempts to run 3 streams at 12,000 feet, freezing occurs on all sets. The CO techs claim that the reach is not exceeded and the reason the customer is experiencing problems is because of cable trouble. I have tested every parameter of the infrastructure and it is stellar.

Me: Let's first look at the cable pair. Did it pass all tests including the longitudinal balance?

Greg: Yes, and it passed the wideband tests with the far end device.

Me: Did you see any interferers or disturbers FEC or CRC errors or impulse noise?

Greg: No.

Me: What was the attenuation, signal to noise, and capacity?

Greg: 42dB, 6dB, and 98%

Me: The problem is the CO folks are wrong. It is too far out, and as I've said before in my columns, "If you exceed the reach you get two things: first, an upset customer, and secondly, an upset technician who cannot do anything about it."

Greg: The CO technicians insist that the problem is with the cable pair. They stated that the Power Influence (PI) on the pair is too high. I told them that it is acceptable at 75dBrnC. They said I should be able to get it below 50dBrnC. They also stated that the equipment vendor told them that 4VAC on the pair is too much.

Me: Those last two statements tell me they know nothing about the infrastructure and what affects bandwidth. Any Power Influence less than 80dBrnC are acceptable. To reduce all PI to less than 50dBrnC would be a miracle.

When Power Influence exceeds 80dBrnC longitudinal AC current can cause a vector shift and in some instances cause the modem to drop. Any AC harmonics in the DSL bandwidth would show up on a wideband spectrum analyzer.

All cable pairs in the field have AC on both tip and ring to ground. This voltage rarely exceeds 10VAC. It means nothing and will have no effect on bandwidth. When the AC exceeds 50VAC it is considered hazardous.

By the way, it's not just a problem with lack of training for the CO; the CO folks at some point have to rely on what they are told, and I can tell you that, time and time again, I've found that the vendor providing equipment for voice, data and video service frequently stretch the truth a bit - or a lot! Whatever they tell you they can achieve in distance, you can cut that by 5 to 10%.

For Pete's sake, give the tech a break and trust him/her when they go through the testing procedure and can show you the results. And save money and time by providing better training to the CO folks so that that you won't hear the expensive phrase "dispatch out" as frequently. Finally, find a way to make the vendors accountable when they lie about equipment reach.