Re: Outside plant protection, fiber cuts, interwebz down oh noes!

[Matthew Kaufman <matthew () eeph com>]

Charles Wyble wrote:
> So allow me to think out loud for a minute....
>
> 1) Why wasn't the fiber protected by some sort of hardened/locked 
> conduit? Is this possible? Does it add extensive cost or hamper normal 
> operation?

Cost, both in implementing (what are likely to be easily-circumvented) 
physical protection mechanisms and the cost of dealing with those when 
on-site doing installation and maintenance.

> 2) Why didn't an alarm go off that someone had entered the area? It was 
> after business hours, presumably not in response to a trouble ticket, 
> and as such a highly suspicious action. Does it make sense for these 
> access portals to have some sort of alarm? I mean there is fiber running 
> through and as such it could carry the signaling. Would this be a 
> massive cost addition during construction?

An alarm did go off, the moment the fiber was cut. In the old days, the 
alarm was gas pressure reduction on the coax followed by loss of 
signal... now it is loss of the optical carrier.

It turns out that the absolute minimum in false alarms is to ignore 
things bumping into the manhole or falling into the vault and to alarm 
immediately if the fiber is tampered with, which is exactly what happened.

A little semi-automated OTDR and you could tell which manhole it is 
without driving down to the CO, too.

> 3) From what I understand it's not trivial to raise a manhole cover. 
> Most likely can't be done by one person. Can they be locked? Or were the 
> carriers simply relying on obscurity/barrier to entry?

I see individuals raising manhole covers and going down to do 
maintenance on their own all the time.

Glass is cheap enough that the right solution to this problem is route 
diversity. An alarm goes off when one path is cut, but you have another 
path that is still running. Now it takes twice as many people to do the 
cutting. And if you really care, you can back that path up with other 
technology like microwave radio.

But it all comes down to cost. ADSL and POTS subscribers in Santa Cruz 
County are willing to pay AT&T money for service that doesn't have 
sufficient route diversity along Monterey Highway. As long as it is more 
profitable to run the network that way, that's how it will be run. And 
people who care, *can* back this up. My home ADSL was down but my 90 
Mbps home microwave link was running fine, and my VoIP was unaffected as 
well. My bank couldn't process transactions (Frame Relay was down) but 
the gas station next door could (VSAT was up). A few years ago it was 
the other way around when Galaxy 4 went belly-up. Either one of those 
*could* pay a few extra dollars a month and have both... and if that 
becomes financially worthwhile, maybe they will. But they can't expect 
their race-to-the-cheapest telco or ISP to do it for them without 
specific contractual agreements to that effect, and frankly a 14-hour 
outage just isn't enough lost business to pay for it. (If it was, I'd 
have a lot easier time signing people up as customers of my south SF bay 
area/north monterey bay area wireless ISP)

Matthew Kaufman