In reply to a post by eckiedoo:

And the copper recovery - "little gold-mines".


Also, I wonder if the redundant ducts may have a residual value, such as for electricty supplies, whether new or providing a more protected environment thinking of the recent storms and associated damage?

NO. there are in the wrong place and the duct will be the wrong colour and would suggest that comms cables were inside rather than a dangerous multi-kv supply.

Thanks, MHC - I had forgotten about the colour-coding.

The copper must have some value, though.

Well the guys in white vans think so ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

I do love these kinds of threads and especially when you get pictures like what Mr Saffron posted.

Any more info on how exchanges are linked / how it all physically works etc?

Yes, we do wander a bit.

I also wonder what differences there are in the organisation of the management etc of the (fibre) network, particularly in connection with the differences, if any, arising from running the fibre from a different exchange, such as Yeovil in this particular case.

Thanks to all contributing! It's good to know i posed an interesting question

I was curious whether it linked from WWYEOV to WWMART in some sort of loop. I suppose it some respects it adds some redundancy and failover so if one link goes down you aren't totally ruined.
Particularly as others have said BT are aiming to decentralise from the old Exchange model being that i suppose in some respects they are quite dated buildings etc.

Food for thought though!

No loop. Just tree and branch topology

Last calculation I did put it at about £5 billion if you rip it all out.

Needs voice as in VoIP to become as reliable as old PSTN and then the issue of power backup for emergencies i.e. fibre ONT needs power to run

In fact, it tends to reduce redundancy; and when there is a failure at one of those more centralised exchanges, eg Yeovil, then a much greater number of subscribers/users are affected.

The nearest parallels I can think of are Railway Signalling (implying Control), Air Traffic Control, National (Electricity) Grid and similar.

As an example of possible effects of such concentrations of very similar telecommunications -

http://www.globalrailnews.com/2014/09/17/network-rai...
"
In January 2015, York ROC will take over from the current control ... controlling signalling between King�s Cross and the Scottish border.
"

If the York ROC "goes down", note the widespread effects.

With the fibre being run from WWYEOV they are now half way through my village and should be at the NGA by end of the week i'm thinking.
In terms of when the NGA will go live (i'm not asking for dates) but would they have to complete the cable run from WWYEOV to WWMART (the exchange my cabinet is connected to) before i can order or shortly after hitting my NGA could the order be placed?