In reply to a post by Zarjaz:

Yes, no splitters in the CBT.

No splitters in the DP nodes either.

There IS splitter(s) in the splitter node though. Suspect you knew that though.

Thanks Zarjaz. That makes sense.

Beyond the Ag Node is the Splitter Node logically then at two levels - Primary Splitter and Secondary Splitter - and are these effectively in the one physical node or physically separated i.e. downstream of each other and all upstream of the DP and finally CBT?

In reply to a post by Pheasant:

Beyond the Ag Node is the Splitter Node logically then at two levels - Primary Splitter and Secondary Splitter -

I'd be interested to know this too. My suspicion is that OR's motivation in bringing ports back individually from CBTs is to make more efficient use of splitters, and as such they'd have x number of fibres into a splitter node and 32x out. They could just work along the desired number of outputs, filling up each splitter as they go and potentially having one CBT span more than one PON.

If you push splitters to the CBT level there is a higher level of split 'wastage', or more complicated splicing instructions/greater quantity of splices required.

In reply to a post by Pheasant:

Beyond the Ag Node is the Splitter Node logically then at two levels - Primary Splitter and Secondary Splitter - and are these effectively in the one physical node or physically separated i.e. downstream of each other and all upstream of the DP and finally CBT?

I would have put money on there only being one level of splitting not two.

I thought it went like this (CBT infrastructure deployments)

1) Head End/exchange
2) Aggregation node
3) Splitter node
4) DP node (not always)
5) CBT
6) CSP *(not always)
7) ONT

* Especially for Pheasant

Edited by deleted (Tue 06-Apr-21 23:28:22)

Not really sure. Hence the question. Was it always single level 32-way split or did they have the primary /secondary split concept ever in reality?

[Make that CSP (not always) too. 😄]

Various Openreach FTTP diagrams over the years....

Ag. Node with Primary and Secondary Splitter arrangement

8-way and 4-way splitter arrangement

Single 32-way Splitter Node

Ag. Node with Splitter Node and DPs

Splitter Node with CBT and drop cables

Yep, as per the Dect’s ‘flow chart’

lets hope your in distance then of the CBT or that migth be in issue

In reply to a post by Pheasant:

Was it always single level 32-way split or did they have the primary /secondary split concept ever in reality?

Openreach certainly released diagrams around 2015 showing 2 level splitting for both the original manifold type and pre-connectorised (including a splitter in the CBT) type but I have yet to hear anyone say it went into production but thats not to say their isn't the odd one out there somewhere

Was two-level splitting the original architecture when they launched FTTPoD and was subsequently refined or updated to become single-level splitting at some point since and especially since mass rollouts began? Dunno.

FWIW I have never come across two splitters in a fibres routing