Work in progress - 7 way microduct (presumed 5/3.5mm) bundle in footway chamber, with reducing coupling from a 7/3.7mm microduct coming from a pole.

https://ibb.co/p13v5t1

In reply to a post by ft247:

Here's a picture of one of the cabinet pairs that has appeared recently: https://ibb.co/R6v77H8

Seems the locals have wasted no time in vomiting on one.

Small cab looks like a power pedestal / metering cabinet. Active gear, OLT etc in the vented enclosure. Looks solid. Won’t mind a bit of pavement pizza! 🤣

No cabs installed around here yet that I can see. I’d be surprised if the conservation lot don’t arc up over the battle grey paint scheme like they made OR repaint some of theirs!

In reply to a post by ft247:

Further discoveries:
...
This can accommodate a 24-fibre unit, which is excessive if splitters are located in AFNs. Either I'm wrong about the 1:16 splits in AFNs, or they have sized the microducts to allow a PtP infrastructure in future.

They may be designing the duct infrastructure to cater for other services overlay. eg if serving mixed domestic /business locations, the ability to offer direct Ethernet PtpP services as well as XGSPON.

Although Openreach keep such infrastructure physically and logically separate, there’s no rule that says CF can’t.

Edited by Pheasant (Fri 12-Mar-21 22:27:43)

In reply to a post by Pheasant:

Although Openreach keep such infrastructure physically and logically separate, there’s no rule that says CF can’t.

In theory you can assign traditional wavelengths (or TWDM slots) not used by XGS-PON to PtP links on the PON.

Some interesting thoughts from an Adtran presentation here: https://www.wecc.org/Administrative/Luhman%20-%2010G...

In reply to a post by ft247:

In reply to a post by Pheasant:

a pretty large triple footway chamber with CF branding has been installed about a 10 minute walk from my place in N1. I’d say it’s been there less than a fortnight.

The triple lid chamber is what has been appearing in my area (SW16). Most are on Streatham High Road, the most major road in the area. I have seen four chambers spaced between 200 and 350m from each other, with every second being sited with a new cabinet.

Looking over towards the Furzedown/Tooting area which they built previously, CF chambers are smaller, only a double lid type but more numerous, spacing 120-300m.

As far as timelines go, the first chambers appeared here before Christmas if I remember right. Sporadic duct unblocking over January and February, microduct up poles a week or two ago, first signs of underground microduct bundle installation today. Many planned roadworks over the coming weeks - I'd say it's two months out if all goes well.

Presumably they’re over-building the new triple-lid chambers over existing Openreach duct network and cutting open/into the ducts they have access to via their PIA arrangements?

It could even be as prosaic as having a “consumer” PON and “business” PON running side by side both XGSPON but the business side may have fewer splits / run back to a separate OLT.

They have after all published a 10Gbit symmetric business service and a 3Gbit domestic service. Are these running on the same glass/PON?

In reply to a post by Pheasant:

Presumably they’re over-building the new triple-lid chambers over existing Openreach duct network and cutting open/into the ducts they have access to via their PIA arrangements?

The CF chambers are always in close proximity to Openreach duct. I had presumed that the standard method was to lay short duct from the CF chamber to break into the existing Openreach chamber; PIA prices exist for this work. I'm not sure if overlaying a duct route is permitted.

There have certainly been no significant new lengths of duct laid in the area, the deployment makes maximum use of Openreach infrastructure.

Yes they aren't digging up the footpath with new wholesale trenching and new ducts around here either, that's for certain. Will be interesting to see how they progress.

In reply to a post by Pheasant:

It could even be as prosaic as having a “consumer” PON and “business” PON running side by side both XGSPON but the business side may have fewer splits / run back to a separate OLT.

They have after all published a 10Gbit symmetric business service and a 3Gbit domestic service. Are these running on the same glass/PON?

I'd say it's more cost-effective to run one physical PON and if need be prioritise traffic at a higher level for now, even with the 3Gbit domestic service. You only have to provide what people are actually going to use! If Openreach can get away with 2.4Gbit downlink on a 32-split, 10Gbit downlink on a 128-split should be ample given typical domestic usage patterns.

I'd be very surprised if the 3Gbit service was taken by more than 1% of home users. Most will be on 150Mbit and typical individual domestic use only goes above 10Mbit on a 5-minute average basis when there's a game or OS update to do.

Even Virgin for the most part get away with something like 1.2Gbit down shared between what I suspect are many hundreds of domestic properties per segment. My If there were only 128 users on my DOCSIS segment I'm sure the service would work perfectly!

The business 10Gbit services probably warrant a separate fibre or wavelength. I wonder how many they sell at £500 per month - outside of media production businesses I can't imagine there is much demand.

Side note: it's interesting to look at what ISPs have reported as their peak demand recently and divide by the number of subscribers. The numbers seem to work out at less than 5Mbit average, even at 'record-breaking' peaks. A 1:128 split on XGS-PON allows for an average of more than 70Mbit per user, and that's with 128 active subscribers per PON. Not every premises passed will take a service, so to my mind XGS-PON is pretty future-proof. If they do start to get saturated it's easy, if a two-level split structure is used, to change to a 1:64 split. And I think by then someone will have 100G-PON in low-cost mass production.

In reply to a post by Pheasant:

Yes they aren't digging up the footpath with new wholesale trenching and new ducts around here either, that's for certain. Will be interesting to see how they progress.

Have a look at public.londonworks.gov.uk and filter by works owner 'COM'. There are quite a network of cabinets planned near you, but I suspect you're a little to the West of where they're building.