Switching to full fibre

I currently have ordinary FTTC and am close enough to the fibre cabinet to get rock solid sync at 80/20 with about 73Mb/s download and 18Mb/s upload speeds. In other words as good as it gets for FTTC. It's also good enough for all my needs.

FTTH is now available at my address and the prices for the 76Mb/s and 145Mb/s tiers are actually a little less than I'm paying for FTTC. So why aren't I jumping at this?

On the 76Mb/s tier the guaranteed download speed is only 40Mb/s. Does anyone know why this should be? It's not like copper which can cause significant speed loss with distance. I don't want to sign up for 76Mb/s FTTH and find my speeds have significantly dropped.

Edited by ppppenguin99 (Fri 18-Jul-25 17:34:27)

In reply to a post by ppppenguin99:

I currently have ordinary FTTC and am close enough to the fibre cabinet to get rock solid sync at 80/20 with about 73Mb/s download and 18Mb/s upload speeds. In other words as good as it gets for FTTC. It's also good enough for all my needs.

FTTH is now available at my address and the prices for the 76Mb/s and 145Mb/s tiers are actually a little less than I'm paying for FTTC. So why aren't I jumping at this?

On the 76Mb/s tier the guaranteed download speed is only 40Mb/s. Does anyone know why this should be? It's not like copper which can cause significant speed loss with distance. I don't want to sign up for 76Mb/s FTTH and find my speeds have significantly dropped.

FTTP is a contended service with upto 30 properties and the overall bandwidth is 2.4Gbps down and 1.2Gbps up so if you do the maths not everyone can always be guaranteed their max speed. I am not one to regular check my speed but when I do I almost always get what I pay for.

Edited by PCJM40 (Fri 18-Jul-25 17:48:32)

Thanks. I wondered if that might be the case. So it could work at full speed on day 1, then drop as neighbours also get FTTH. Unless a few neighbours are diehard downloaders who max out their connections there will be a statistical multiplexing effect.

This is reminiscent of contention in the old days of ADSL.Is there any meaningful contention on FTTC?

In reply to a post by ppppenguin99:

Thanks. I wondered if that might be the case. So it could work at full speed on day 1, then drop as neighbours also get FTTH. Unless a few neighbours are diehard downloaders who max out their connections there will be a statistical multiplexing effect.

This is reminiscent of contention in the old days of ADSL.Is there any meaningful contention on FTTC?

Yes the FTTC cabinet has a number of fibres going to it (I honestly don't know how many) and the bandwidth of those fibres is spread across the properties connected to the copper line cards.

FTTP is far better than FTTC even if you are living on top of the cabinet

If several neighbours sign up for the top tier of 900Mb/s that might impact the parsimonious few who only have 76Mb/s.

My other potential problem is that I'd like the ONT about 8 metre from the external fibre termination, where my master socket is fitted in what I laughingly call my network closet. The cable from outdoors to the master socket runs through a hole in the wall to the space under the floorboards. I think it would depend very much on getting a friendly Openreach guy who's willing to use the old cable as a draw tape for the new fibre cable.

In reply to a post by ppppenguin99:

If several neighbours sign up for the top tier of 900Mb/s that might impact the parsimonious few who only have 76Mb/s.

Its all ifs buts and maybes, we can all over think it but honestly its a no brainer of a switch.

Just for reference 900Mbps is no longer the top tier available on the Openreach network.

Regarding getting the cable through, you can either try to arrange for the fibre to be run all the way to the closet or just get the ONT put on an outside wall and run a ethernet cable the remaining distance.

In reply to a post by ppppenguin99:

If several neighbours sign up for the top tier of 900Mb/s that might impact the parsimonious few who only have 76Mb/s.

My other potential problem is that I'd like the ONT about 8 metre from the external fibre termination, where my master socket is fitted in what I laughingly call my network closet. The cable from outdoors to the master socket runs through a hole in the wall to the space under the floorboards. I think it would depend very much on getting a friendly Openreach guy who's willing to use the old cable as a draw tape for the new fibre cable.

Even if some near neighbours on the same PON take a 900 Mb or even a 1.6Gb service , and every one of the 30 splitter outputs , it’s extremely unlikely that every user is maxing out their service simultaneously, plus OR employ DBA , dynamic bandwidth allocation so even in peak usage, it isn’t the case everyone is given the same low ‘speed’ the higher bandwidth’s although suffering a percentage reduction have more headroom anyway , so if DBA applies a 10% reduction to alleviate congestion (not very likely) 900 goes to 810 , 80 goes to 72 etc …what’s more , I suspect your minimum speed guarantee may be incorrect anyway and is for FTTC or even your own current FTTC circumstances ,
As an example , the FF100 (full fibre ) , with BT/EE is actually a 150Mb service and the guaranteed minimum is 100Mb ….anyone on F2 (80Mb on FTTC ) can normally get FF100 when upgrading to FTTP for no increase in cost although potentially with a new minimum term , that’s seems to me the obvious upgrade path for those that don’t need any more ‘speed’ than what they get from FTTC .
I would take any minimum speed guarantee with a huge pinch of salt , you are not artificially restricted to the MSG , it’s nothing more that a sop to the regulator and advertising authority

The rest of your requirements, using the existing copper cable to draw in an optical one can’t really be predicted, it depends on who turn up on the day , some will be OK with that , others will refuse

Edited by Iniltous (Sat 19-Jul-25 08:58:26)

You could try https://community.plus.net/

In reply to a post by Iniltous:

using the existing copper cable to draw in an optical one can’t really be predicted, it depends on who turn up on the day , some will be OK with that , others will refuse

May be if the OP wants to put in the legwork they can do what is often suggested on this forum, install conduit point to point with a draw string so it becomes a no brainer for the installer. If it isn't straight forward then its not likely to be accepted as a workable solution.

In reply to a post by Iniltous:

In reply to a post by ppppenguin99:

If several neighbours sign up for the top tier of 900Mb/s that might impact the parsimonious few who only have 76Mb/s.

My other potential problem is that I'd like the ONT about 8 metre from the external fibre termination, where my master socket is fitted in what I laughingly call my network closet. The cable from outdoors to the master socket runs through a hole in the wall to the space under the floorboards. I think it would depend very much on getting a friendly Openreach guy who's willing to use the old cable as a draw tape for the new fibre cable.

Even if some near neighbours on the same PON take a 900 Mb or even a 1.6Gb service , and every one of the 30 splitter outputs , it’s extremely unlikely that every user is maxing out their service simultaneously, plus OR employ DBA , dynamic bandwidth allocation so even in peak usage, it isn’t the case everyone is given the same low ‘speed’ the higher bandwidth’s although suffering a percentage reduction have more headroom anyway , so if DBA applies a 10% reduction to alleviate congestion (not very likely) 900 goes to 810 , 80 goes to 72 etc …what’s more , I suspect your minimum speed guarantee may be incorrect anyway and is for FTTC or even your own current FTTC circumstances ,
As an example , the FF100 (full fibre ) , with BT/EE is actually a 150Mb service and the guaranteed minimum is 100Mb ….anyone on F2 (80Mb on FTTC ) can normally get FF100 when upgrading to FTTP for no increase in cost although potentially with a new minimum term , that’s seems to me the obvious upgrade path for those that don’t need any more ‘speed’ than what they get from FTTC .

DBA doesn't work that way and is upstream only, Sir. Downstream the shaper satisfies minimums then distributes the rest based on a QoS algorithm, involving how full buffers are, if smaller packets may fill gaps, etc.

The minimum downstream speed is a CIR configured on the downstream shaper, the maximum the subscriber has available, their actual tier, is the PIR. A customer with tons of traffic hitting the OLT in many flows will get higher speeds than someone running a single flow as packet loss will impact the single flow more heavily than the multiple flow customer. Openreach call the speeds prioritised and peak in at least some of their documents.

Bittorrent and Usenet with many connections are both PITAs for degrading speeds on PON due to the many flows thing.

However very unlikely to be an issue to OP, higher speeds come with lower guarantees relative to the tier for obvious reasons. ISPs can and do advertise higher guarantees as those are likely to be reached all the time but the network operator itself can't.

The people on 76 Mb might see an impact from heavy use on the PON but it'll be far less heavy an impact than the one people on a gigabit would see and they'd be less likely to notice even if the PON were heavily utilised. If so scared of contention better to pay for a DIA regardless. Can be assured you're getting 'what you pay for'.