CBT not on my pole, does it matter?

[cliffw]

Hi everyone,

I've been waiting with baited breath for ages to be able to get FTTP and I've seen CBTs go up on the poles both before and after the one which my telephone line comes in from (mine is the only property served by the pole). Does this mean I'm unlikely to be able to get FTTP once it becomes active or will they run the cable back from the next pole which is one along?

Many thanks for your help ☺️

[imjolly · Accepted solution]

They will just run fibre from the nearest CBT to your pole and then to your home

[cliffw]

Thank you so much.

I'm also a bit paranoid that there are 6 properties by the first CBT, which has 6 ports and 5 properties near the closest CBT which has 4 ports! One of the ones near me is an annexe.

Do you know if it's more first come first serve please, or a potential provisioning mistake? (assuming the annexe has its own phone line)

[pippincp]

I would go with 1st come 1st served although another connection can be brought from another nearby CBT.

Better safe than sorry.

[iniltous]

The CBT’s that Openreach use are , 4, 8, or 12 port , there isn’t a 6 port , so chances are the one in question it’s an 8 port with a demand of 5 , the way an area is dimensioned with CBT’s , is a 4 port serving a max of 3 addresses, 8 port services a max of 7 addresses ( so always at least one spare port ) , the exception is a 12 port can have 12 addresses allocated, if there are more that 12 addresses , another CBT is provided alongside. The network is designed with more rather than less ports for the potential demand, for example, you could have an 8 port serving 4 addresses, ( a 4 port would be 100% allocated so cannot be considered as at least one port has to be spare so an 8 port is provided ) so 4 ports ‘spare’ on that 8 port CBT .

Its extremely unlikely that the network won’t be sufficiently ‘big’ , and even the most optimistic network planners wouldn’t predict 100% take up of OR’s FTTP , so provided your address was surveyed , it will be included in the PON plan, as will every other address in that area.

If you are served from a ‘ carrier pole ‘ then the CBT being on the DP pole nearby and the ‘drop cable’ originating at the DP pole and going ‘via’ the carrier pole to your home is a pretty common situation, for copper as well as fibre connections, a carrier pole is required if a direct span would be over length, or you need to go around a corner or an obstacle.

[cliffw]

What a great answer! Thank you.

It's a bit dark outside to look now, but is it the case that if it has 6 circular nodules sticking out then it's actually the twelve port? I'll give it all a double check tomorrow in case I counted wrong.

[iniltous]

Try searching Openreach CBT for images, OR use a couple of manufacturers, Alt Nets can use similar equipment, but may use a different formula for allocating ports to demand, and don’t necessarily aim for 100% coverage.
As stated , there isn’t such a thing as an Openreach 6 port CBT , hence my assumption it’s an 8 port, there is ( obviously ) a circular nodule for each port , these are where the connectorised dropwires are plugged into the CBT , each port has a removable port cover to keep the port ‘clean’ until it’s required.

The port layout is , 4 and 8 port CBT’s are , 2 rows of 2 and 4 rows of 2 , the 12 port CBT is 4 rows of 3 , the middle port of each row slightly raised resembling a ‘^’ , the cable tail for a CBT enters the enclosure close to the bottom 2 ( or 3 ) ports , so on an 8 port CBT it can make those bottom 2 port’s difficult to see , especially if looking at it from the foot of a pole