''fibre optics ''

Did BT GPO use fibre under roadside manhole covers for anything before broadband ?
If so what year did it start and what was it used for ?

Andy

Yes, and many many years, knew people splicing fibre in 1996
Leased lines, and the old ATM network that linked all phone exchanges.

My first fibre service from BT was installed in 1989, previously 'high' speed services were delivered to the site over transverse screened copper cable.

The ISDN lines in this building came in on fibre in 1996 as part of a new build

BT used fibre many, many years ago for voice lines - the dreaded TPON - Telephony over Passive Optical Network.

This leap into new technology (60's and 70's I think?) caused problems with subscribers in TPON areas not being able to get ADSL until a "copper overlay" was installed - installing copper pairs instead of the TPON fibre.

Milton Keynes was the classic sufferer from this.

The logic of replacing optical with copper (for ADSL) and then with FTTC amazes me but GPO / BT always had a habit of either doing wonderful thing with old technology (the original STD dialing with Strowger electro mechanical kit) or getting stuck down a technical dead end (at the time) with TPON.

FTTC in 10 years time will probably seem a stupid move as well!

Fibre has been used in the trunk (national ) network since at least the 70s, and has been used in the local access network for leased lines since the 80s.
BT installed an extensive network covering the CIty of London during the 80s for banks/traders. TPON came in the early 90s to provide PSTN/ISDN services to new build sites but the electronics at the end was ultimately a dead end.

I remember back in about '80 or '81 being involved in a project which need fibre optics for control and communications. We brought in some of the technology from BT. And it was not cheap.

I bought some fibre from Tandy in 1986 for a little test project.

In reply to a post by greenglide:

BT used fibre many, many years ago for voice lines - the dreaded TPON - Telephony over Passive Optical Network.

This leap into new technology (60's and 70's I think?) caused problems with subscribers in TPON areas not being able to get ADSL until a "copper overlay" was installed - installing copper pairs instead of the TPON fibre.

Milton Keynes was the classic sufferer from this.

The logic of replacing optical with copper (for ADSL) and then with FTTC amazes me but GPO / BT always had a habit of either doing wonderful thing with old technology (the original STD dialing with Strowger electro mechanical kit) or getting stuck down a technical dead end (at the time) with TPON.

FTTC in 10 years time will probably seem a stupid move as well!

FTTC is unlikely to seem like a stupid move - BT have been careful to build their FTTC deployment in such a way that it's an easy step to FTTP (replace a VDSL2 DSLAM with a splitter, replace the copper tails with fibre tails to go from FTTC to GPON or XGPON). As long as we continue down the route towards fibre everywhere, it's a good first step.

The VDSL2 DSLAM may well be capable of voice too, meaning that in future the cabinet to exchange copper could vanish

My new build estate had a TPON setup when we moved in, rendering DSL a no go until copper overlay was implemented.

There is probably fibre still underground, at least to the old TPON cabinet. Surely BT could swap this out for a DSLAM and quickly provide FTTC to the houses?

I've since moved away but they still suffer from sub-2Mbit speeds.

In reply to a post by MrSaffron:

The VDSL2 DSLAM may well be capable of voice too, meaning that in future the cabinet to exchange copper could vanish

That is the on-going debate about whether telephony should be capable of being independent of the customers power supply. Or is battery back up enough ... &c &c

Possibly the "wrong type of fibre" and would require additional equipment at the exchange.

battery backup is enough as far as ofcom is concerned

Also a FTTC phone line with its own battery backup, could power the copper part anyway.

Edited by MrSaffron (Mon 12-Mar-12 13:34:52)

The phone coming into your house is a dinosaur.

most people these days have mobiles. why have (and pay for) both?

In reply to a post by Moradin:

The phone coming into your house is a dinosaur.

most people these days have mobiles. why have (and pay for) both?

The ONLY reason I have a landline is the requirement to have a voice service to have broadband, I think if that were removed then there would be a big fall in the number of voice lines in service.

In reply to a post by Kiggs:

My new build estate had a TPON setup when we moved in, rendering DSL a no go until copper overlay was implemented.

There is probably fibre still underground, at least to the old TPON cabinet. Surely BT could swap this out for a DSLAM and quickly provide FTTC to the houses?

I've since moved away but they still suffer from sub-2Mbit speeds.

I have experience of the dreaded TPON fairly often. In the Kinswells area of Aberdeen TPON was implemented, Sky DSL is incompatible with TPON, but sales don't seem to know this and go ahead and place an order for DSL on a TPON line!

In reply to a post by connormill:

I have experience of the dreaded TPON fairly often. In the Kinswells area of Aberdeen TPON was implemented, Sky DSL is incompatible with TPON, but sales don't seem to know this and go ahead and place an order for DSL on a TPON line!

That must be a frustrating experience !

I'm with Sky broadband having recently moved to them from O2 broadband.

Yes, BT were using fibre for junction cables way before broadband and still pick up patent royalty payments for fibre deployment techniques used by other operators worldwide.

Edited by deleted (Mon 12-Mar-12 20:43:07)

In reply to a post by warweezil:

The ONLY reason I have a landline is the requirement to have a voice service to have broadband, I think if that were removed then there would be a big fall in the number of voice lines in service.

Seconded - this is one of the things that has always annoyed me about VirginMedia's pricing. You can have cable modem without voice service but you pay for the missing voice line.

MrSaffron explained to me a while ago that OpenReach's costs don't reduce very much if you take the voice service away and have ADSL/ADSL2+ without voice.

with VDSL/FTTC and FTTP services I hope there will eventually be a product that is internet without voice - but I suspect that for FTTC there will only be a £0.50 a month saving or so. FTTP could be more.

Placing the order is actually what they are meant to do. Then it goes to Openreach who will see if a copper pair to the exchange is available and will move the phone line onto that and let the ADSL order progress, or if non-available will fail the order.

Kingswell has copper overlay, but not enough for every line on the TPON.

Fujitsu did a trial running a small DSLAM alongside the TPON hardware, but cost wise possibily not worth it, but with BDUK things may change.

With FTTP nothing stopping you having just the fibre for internet

the retail providers may prefer you to take a voice line rental, to help underwrite cost of data usage.