By backhaul, I assume you mean backhaul from the exchange back to the nearest WDM/Metro node? Rather than backhaul from FTTC into the exchange?
Yes the exchange ATM backhaul on to what used to be known as MSiP. That exchange was still 20CN when the above photo was taken.
Migrating live copper offers something that live fibre doesn't ... it can be connected to two points in the exchange at a time, allowing temporary bypasses to be wired in when a migration is needed.
No idea how they did it, perhaps during the migration to 21CN? I certainly recall there being several outages in the wee small hours usually at around 1am - despite me being on BE at the time. During that period there was lots of night work going on and I'd see lights on when coming home at night.
Ive been trying to rack my brains what was at the front where the new ODF now is. I think it was where or at least very near to where the
DACs units and LDU's used to be.
BS may also be able to help me out here, but I
think just to the left of that photo there may also some old fashioned black dial like meters which iirc were explained to me as pressure guages/monitors for something or other which was in the basement? Really cant recall anything much about what was downstairs as we were only allowed a quick peek around the door. The excuse at the time was something about a build up of gasses and it wasn't very nice down there without masks. [Thinking again - could it have been flooded at some time and stunk? Im sure they said something about H&S]. Im not certain on my facts here... long time ago.
What used to be at the front in the row where the fibre trays now are (such as the LDU's, DACs and those pressure gauge thingies)- I cant recall seeing any of that now there. That said the other day was a flying visit and I was more looking at the fibre trays than what was around it, so may have missed it.
In fact just looking through some of the photos I didn't publish and on this photo of the
geostream_hub, if you look to the left it shows what would now more or less now where the new ODF is located.
They
definitely have done some major shifting around and upgrading in there. There used to be a lot of floor space, now there is hardly any and the LLU MSANs take up quite a fair chunk of it.
I think the yellow cables coming in top-left are the fibres coming in from the aggregation nodes; 576 fibres when full.
The cables exiting top-right are the hydra cables that take those fibres into the handover layer 2 switch.
I think this is, essentially, the MDF of the optical world.
Calling it an optical equivalent of the MDF is quite a good comparison.
I think the photos you posted, the top one is an FTTx OLT and the bottom one is possibly what is classed as
Element Manager for ECI cabs when we talk about DLM. They come under differing names depending on manufacturer, but its kind of the FTTC equivalent of the Fujitsu geostream hub for the adsl MSANs. These are the master switches/hubs and convergence of the 'xbrand' dslams or msans. Could be very wrong here though as Im assuming from descriptions, so please dont take it as gospel.
One of the things I'd like to do is visit an exchange that has FTTC/FTTH head end equipment but something Ive not got around to doing or even asking. It would be even better if like last time they designated someone from BTw to guide me round and explain what everything was. On that occasion most of the visit was at a larger exchange.
The second (1/2) day was my own exchange with an Openreach guy... that was also quite interesting because they'd taken my phone no and plotted its route my traffic would take.. eg your copper terminates here. This is your line on the MDF, from here it goes to this MSAN, then it goes over here (waving hands in air at the overhead cables) to this ODF.