VM infrastructure question
 

The town where I live is having FTTH installed and I'm blogging progress as it's a huge undertaking and brings lots of benifits.

I,ve found developer information online but I woul like to know the difference between a L3 and L4 cabinet ( one cabinet was open and had 48 fibre connections in it, is this a typical Lx)

Green micro duct goes to each Toby and home run back to the cabinet, what is the green and red duct for and are all cabinets connected in some form of data ring.

The above is so I can expand the blog with some form of rough schematic.

Ian

Re: VM infrastructure question
 

L3 cabinets are mini nodes, generally feeding up to 500 homes each. They have a direct feed to the larger VHUB unit (serving a node area of up to 3000). They are fed on multi core blown fibre along the red/green larger blown fibre ducts. Each L3 cabinet will feed up to 10 L4 distribution cabinet (48 connections per cabinet) in a direct trunk feed from its parent L3 cabinet. In turn each L4 cabinet then has up to 50 direct blown fibre feeds to properties that terminate inside the toby (termination box).


The developers guide has some information of the high level blown fibre topology if that's any use? www.virginmedia.com/developer.

HTH

Re: VM infrastructure question
 

Weesteev,

That was just what I was after, the town appears to have two VHUB units and in some places two identical cabinets next to each other and on the pavement the contractors had sprayed L3 & L4, hence the question.

Many thanks for the info and link

Ian

Re: VM infrastructure question
 

That siamese coax-blown-fibre tube is interesting, I didn't notice that before. Presumably that's for new HFC infil areas to offer an upgrade path to XG-PON or similar in the distant future

From what I remember, RG6 has a solid dielectric - otherwise it might have been semi-possible to blow fibre down the dielectric of an existing coax cable... Probably not commercially viable however, due to kinked pre-existing cabling, internal radius, friction, etc.

Re: VM infrastructure question
 

The siamese blown fibre option is a future proof upgrade option for developers where we deploy coax based internal wiring but who knows what the future holds! There is actually a new version of the developers guide due out soon and this reference has now been removed, we will only be pre-wiring RG6 coax only in FTTP new builds.

Re: VM infrastructure question
 

That makes sense - I mean presumably there would only be one ONT per property anyway for the forseeable future.