PDA

View Full Version : Can chorus tell which cables have been damaged by the earthquake?



64etert
05-03-2011, 10:21 PM
So chorus says "All of our telephone exchanges and the vast majority of roadside cabinets are up and running" in christchurch, so if a cable from the exchange/cabinet that goes to a street is damaged, can chorus tell if that cable is damaged without a user reporting their broadband is not working?

8ftmetalhaed
05-03-2011, 10:58 PM
Probably, in that they'll either not be receiving signals or the lines that are listed as being connected won't respond. Probably something similar to a tracert or ping, they'll likely have kit to identify where, if any faults are. (Like how vodafone can tell from their customer service line that there was higher than normal voltage on my phoneline)

somebody
06-03-2011, 08:37 AM
A number of the main cables out of the exchange are pressurised (for a number of reasons)- if they're damaged they can detect the change in pressure at the exchange.

With cabinets it's easy - since they're "smart" cabinets, they'll have monitoring/management tools which interact with the electronics in them.

As for the cable going from the cabinet to someone's house, that's a little bit more difficult, but doable, using the monitoring gear which will sit in the cabinet.

Chilling_Silence
06-03-2011, 09:03 AM
mmm going from the Cabinet / Exchange to the Home is where they'll likely have a harder time. The line might not be up because of a power outage, a line problem, an internal home-wiring issue etc.

But like somebody says, from Exchange -> Cabinet they can :)

decibel
08-03-2011, 08:37 PM
5530 Network analyser has an overview of all the DSL network.

Terry Porritt
08-03-2011, 09:20 PM
Also reflectometry methods have been used for years to detect and locate breaks in transmission lines:

http://en.wikipedia.org/wiki/Time-domain_reflectometer

dugimodo
09-03-2011, 12:08 PM
They don't specifically monitor user lines for faults, it would just be far too much to manage. As mentioned some cables are pressurised and any break in them will trigger an alarm, generally these are not the cables feeding your house.

For the most part unless someone reports a fault telecom will not normally notice an individual line is faulty, they can however remotely test them once a fault is reported and quite accurately get an Idea of the state of the line.

Ultimately though there is no substitute for a techinician in the field with test equipment, cable faults are sometimes found by someone walking the route looking for damage. Yes they do have instruments that can tell how far it is to a break, but that doesn't always work.