Vadim Antonov <avg@pluris.com> writes:

Yep. I would say that telcos have rather strong incentive to keep PDH in place. It may actually be a good deal for IP people -- you can get more capacity at a lower price, and handle redundancy at level 3 (hey, interior re-routing is fast).

You've been retired for too long when you start believing that telco price == good deal for any package at all. Fortunately, traditional PNOs are facing real competition in various parts of the world already, with all hell breaking loose in these parts Real Soon Now.

Of course, to get advantage of that practice one may want to work closely with telco to understand their modes of failure, and write a language protecting topology of his network overlay.

Well, maybe if you *were* the telco this *might* work a la FMS. :) In practice, though, I would want to have redundancy there in a simple way, namely through SDH or SONET. I believe this is what lots of carriers are negotiating amongst themselves (each not trusting the others to actually provide real PDH protection redundancy properly), which may be of some follow-on benefit to the retail market. Also, I think you will find plenty of people here who are so fed up with backhoe fade and broken PDH protection switching that they will pay good money for capacity provisioned over SONET rings. Ironically, facilities-wise, SONET is much cheaper than PDH support for protection-switching.

...

You don't need an additional MUX, you don't need extra DAXCs, and you don't need to scurry around reprogramming lots of equipment when someone wrecks your fibre.

It's technical staff who's doing all the scurrying. Sales people already got their comission and are quite happy.

While this is healthy cynicism about PNOs, there is the potential pain of heavy downtime penalty clauses that I hope all major ISPs and other purchasers have started getting written into their capacity contracts when they're paying anything close to normal prices.

My prediction is that redundancy of telco data services won't improve at all until they find a way to reconcile need for redundancy and desire to sell all the capacity they got.

I don't agree. In fact, there are extant counterexamples. Unreliable service costs business, and SONET/SDH rings elminate most of the most common causes of unreliable transmissions facilities. I would hope that Worldcom's PNO side will lose alot of revenues, in the face of the recent cuts, which amply demonstrated their non-deployment of SONET rings along the fibre paths in question. They deserve it, too. Shame on them. Sean.