spare fibers

Sun Jun 16 22:42:31 UTC 2002

Almost without exception, "ring topology" implies a single-carrier doing physical 
layer provisioning and support. In the case where multiple points are under 
attack in a concerted effort to knock out service (including the failover 
capabilities), it's either an "inside job" or, at the least, one where 
intelligence relating to individual SONET backbones and rings has been obtained 
from various sources for the purpose of thwarting such _self-healing_ 
capabilities that are usually afforded by SONET/SDH. 

In the not too distant past (during the pre-sonet and early SONET days when N+1 
automatic protection switching was used instead of counter-rotating recovery 
schemes) we saw this occur, albeit infrequently, during periods of labor unrest 
and other tense forms of situations relating to competition (where folks feared 
for their jobs) along the NY-NJ corridor and in certain parts of California, to 
name just two that I recall off the top of my head. Until recently (post 9-11), 
however, it was hardly a matter of overwhelming concern. Today it is becoming 
more so a matter of heightened concern. Meshing through the use of diverse 
providers' facilities may prove to be the ultimate means of protection, with the 
proviso being that those providers are not all sharing the same physical routes. 
fwiw.

FAC

> 
> 
> Hi Daniel and all,
> Yes, multiple fiber in multiple conduits, traveling multiple paths is the 
> best way to insure something's going to have connectivity.
> Ring topology is what I've seen mostly for best protection, if something 
> goes down, restoration takes milliseconds and is automatic. Worst case, is 
> some contractor digs up the place where your fiber enters your building and 
> severs everything....not much you can do about that kind of outage.
> 
> 
> At 20:41 6/16/02 +0200, you wrote:
> 
> 
> >Hi blitz,
> >
> >I think that you talk about multiple outage in the Telefonica
> >Network in Spain cause by sabotage. (48 fibers in 4 points  at the same
> >time)
> >
> >I see ok the interest of the ministry, is necessary to assure that outages
> >don't affect to the national infraestruture.
> >
> >In our case we build our network over diverse companys with diverse path
> >in their fiber network. I see ok, that all companys that operate basic
> >services do it and they will have backup and emergency plans.
> >
> >Regards,
> >Daniel
> >Intelideas
> >
> >
> >On Sun, 16 Jun 2002, blitz wrote:
> >
> > >
> > > The Spanish ministry of science and technology has asked
> > >     telecommunications companies to activate a backup plan in the
> > >     case of such emergencies in future.
> > >
> > > Spare fibers in the same duct ;-?
> > >
> > > Doesn't sound like it would be much protection from "backhoe fade"...heh
> > >
> 
> 