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Old September 30th 18, 12:34 PM posted to uk.telecom.broadband
R. Mark Clayton[_2_]
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Posts: 587
Default Openroach turbo master baiting too busy to install fiber

On Friday, 28 September 2018 21:15:05 UTC+1, Vir Campestris wrote:
On 28/09/2018 11:32, R. Mark Clayton wrote:
Interesting - 10Gbps fibre modems are as opposed to for 1Gbps.

I have no data on that.

I looked it up. 7 seems to have prices for 1k off.

Can they use a diffraction grating to extract multiple beams from the same fibre?

It's possible. Whether it's cost effective is another matter.

A diffraction grating costs pence, however setting it up accurately would be difficult.

It may be that all the fibre modems are using the same colour anyway.

They don't need to be colour sensitive. However this solution has problems in the uplink direction - splitting a beam in the field is probably pretty simple - it could be done in a passive module. Merging them again is very difficult, so the uplink would either be lower bandwidth or by other means (copper).

As 7 sort of points out this is a frequency division multiplex. It might be easier to statistically multiplex 'bundles' of data for the same switch at the exchange and distribute these to high speed switches at the cabinet - these would unbundle for 10Gbps switches to say 100 users or alternatively just lay 8 core fibre (as at present AIUI).

The idea of laying 3456 fibre cables to cabinets that where I am serve at most a few hundred premises is clearly ridiculous.

In any event it is the cost and difficulty of getting the fibres to the premises that is the obstacle. Even if you put them in 10cm deep micro-trenches they will still get severed every time any other utility has to dig up.