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[waltergmw]

@ Kitz,

Disregarding job titles (excepting to say I only consider myself to be an interested amateur), I hope we can agree that the BT Group have some of the most astute analysts around.
It seems most unlikely that there is a sound business case for any further developments based upon FTTC technology.
However there is every reason to suggest from a political perspective that jam tomorrow is still being investigated.

Given that there is no Universal Service Obligation for any broadband service, it seems there is no reason to make any improvements at all.
Assuming the figure I recall of 33,000 FTTCs and an installation cost of 1 person-day (Probably 2 * half days) and materials costs of say Ł750 per cabinet plus service disruption consequences, the resulting total costs are so large for small (yet to be established) gains as to render the entire concept quite beyond credibility.

EDIT
On the other hand, even though I accept this is over-egging the pudding a bit, the picture below is my VM connection at about 600 m from my VM Fibre cabinet.

Kind regards,
Walter

[Chrysalis]

I found it by searching "ECI, vectoring, line card", as Id heard before it was possible, but it wasn't always practical as ports/pairs may be wasted. 


>> Now I wonder what choice Beattie will make for her "ECI Cabinets"?

I suppose it depends how much and how often they want to avoid this :-

It becomes necessary to send technicians to the street cabinet to perform some cable management.

Its a shame theres no module that could be slotted in to the existing M41s rather than having to replace the whole dslam. 
If anyone had the weight to get ECI to provide such a thing then youd think it would be BT...  but since theres no news on this front I assume that its not possible.

Theres an awful lot of ECI cabs out there that are going to need to be upgraded 

BT cant demand it.

At the time BT is rolling out M41's a product already exists the V41, so ECI would just say to BT you brought the wrong product and rightly so.

Maybe BT will just do the per card vectoring as "its cheaper", and as such we will not see vectoring at full effeciency.  I still cant imagine a situation of BT swapping out all their ECI dslams when they have only just been rolled out.

Also to BS yes I maintain my view BT were very slow to trial this, also I dont like how hush hush BT are, but to hide information is valuable for them as only they know how good their cabling is, how they are deploying vectoring etc.  BT wont want people to know the details because then people will know the potential and when underperforming lines occur (As they do now) they dont want end users to have ammo.

[Chrysalis]

Reading that link, it would appear its pretty much in its infancy with Telco's and not all the trials went swimmingly ?? Another example of individuals mistakenly seeming to know more, than the actual industry experts.

Perhaps if various arms of BT were somewhat more open & transparent for the benefit of the no doubt tiny minority of EU's who are actually interested in such matters, there would be far less assumption, supposition & outright wrong conclusion drawing?

It would also perhaps not be too bad an idea to occasionally filter some details down to the 'Field guys' as I'm sure it would help for whenever they end up visiting an 'interested' EU.

FWIW, here's a couple of examples of when significant changes to service were implemented that caught EUs (& apparently ISPs) by surprise (including Plusnet - actually owned by BT):- 

*Change from 8c profile (Max DS sync speed 40 Mbps / US sync speed 10 Mbps) to 17a profile (Max DS sync speed 80 Mbps / US sync speed 20 Mbps)
*Revision of 17a DS band plan tones from Maximum of 1939 to 1959 (Huawei DSLAMS)
*Very recent HG612 modem firmware updates, including revised band plan tones & apparently switching SRA on (Seemless Rate Adaption)

 

when was SRA turned on? I not seen any such reports.

incidently very good post, you are bang on right, that openreach seem to have a superiority complex where they feel they can just make changes here and there randomly without telling anyone.

[Chrysalis]

Theres an awful lot of ECI cabs out there that are going to need to be upgraded 

Nods in agreement. 

....and to all those who now complain why did not BTOR install cabs with vectoring capable line cards etc inside them from the start....

You need to ask yourself would you have been happy for YOUR cabinet not to have been done at all because the costs of everyone else's cabinet was going to be higher because of the more expensive vectoring-capable-cards.
So YOUR cabinet gets nothing as there is no more money for it.
There would have been screams of outrage on TBB, here, ISPreview and the rest on how we don't care about some tech in the future we just want better speeds 'now'.

I wonder if I should apply for Liv Garfield's job now that she is moving on......?

The thing is I would be very surprised if its cheaper to.

Pay for M41
rip it out
pay for someone to rip it out
Buy a V41
pay for someone to put it in
possibly compensate customers for service outage

instead of

Buy V41 from start.

I can excuse BT/openreach for not starting out with V41 from day 1 because I believe at that point they were not considering vectoring and had bigger plans for FTTP.  But the moment they had vectoring as a consideration really any ECI's still been installed should now be V41's.  If they still putting in M41's today that is aweful business sense.

Maybe this is why the openreach CEO is really leaving?
for incompetance, apparently she had a bad rep from openreach staff as well.

Basically whats happened is this.

Every exec who has a budget they in charge off wants to make their existing annual figures look good.  They may well approve cheaper but less future proof tech to make existing years figures to look good knowing full well there is a big price to pay in the upcoming years, but they will also know by then they may have left said company and they wont care.

My predicition is either we wont see vectoring soon, BT will deem it not financially viable, worth it.

Or we will see a 2 tier vectoring, HG cabinets getting proper vectoring as only need addon card, ECI cabinets getting per card vectoring and as such performing much worse.  We may even see vectoring only been rolled out to HG cabinets with none at all to ECI.

[Bald_Eagle1]

when was SRA turned on? I not seen any such reports.

It seems to have happened when the modem firmware was updated by BT:-

Code: [Select]


# xdslcmd profile --show

Modulations:
        G.Dmt   Enabled
        G.lite  Disabled
        T1.413  Disabled
        ADSL2   Enabled
        AnnexL  Disabled
        ADSL2+  Enabled
        AnnexM  Disabled
        VDSL2   Enabled
VDSL2 profiles:
        8a      Enabled
        8b      Enabled
        8c      Enabled
        8d      Enabled
        12a     Enabled
        12b     Enabled
        17a     Enabled
        30a     Enabled
        US0     Enabled
Phone line pair:
        Inner pair
Capability:
        bitswap         On
        sra             On
        trellis         On
        sesdrop         Off
        CoMinMgn        Off
        24k             On
        phyReXmt(Us/Ds) Off/On
        TpsTc           AvPvAa
        monitorTone:    On
        dynamicD:       On
        dynamicF:       Off
        SOS:            On
        Training Margin(Q4 in dB):      -1(DEFAULT)


I haven't seen any evidence that it actually does anything in my logs though.

[Chrysalis]

ok thanks, that is very interesting.

but your sync speed doesnt move right? stays the same all the time unless disconnects?

SRA by its nature breaks BT wholesale IP profile system, so for that reason I believe they kept it off, eg user loses sync with dslam, the ppp connection drops, sync is reestablished, ppp logs back in, when ppp logs back in the ip profile is updated.  If SRA is used the PPP stays active and as such the IP profile wont keep up with sync speed changes.  So it be itneresting if BT are planning to change the IP profile system.

also on the comparison I see they disabled g.lite and t1.413, annexl, finally dynamicF.

here is mine

Code: [Select]

# xdslcmd profile --show

Modulations:
        G.Dmt   Enabled
        G.lite  Enabled
        T1.413  Enabled
        ADSL2   Enabled
        AnnexL  Enabled
        ADSL2+  Enabled
        AnnexM  Disabled
        VDSL2   Enabled
VDSL2 profiles:
        8a      Enabled
        8b      Enabled
        8c      Enabled
        8d      Enabled
        12a     Enabled
        12b     Enabled
        17a     Enabled
        30a     Enabled
        US0     Enabled
Phone line pair:
        Inner pair
Capability:
        bitswap         On
        sra             Off
        trellis         On
        sesdrop         Off
        CoMinMgn        Off
        24k             On
        phyReXmt(Us/Ds) Off/On
        TpsTc           AvPvAa
        monitorTone:    On
        dynamicD:       On
        dynamicF:       On
        SOS:            On
        Training Margin(Q4 in dB):      -1(DEFAULT)


[ryant704]

ok thanks, that is very interesting.

but your sync speed doesnt move right? stays the same all the time unless disconnects?

SRA will sync, for example 26Mbps then if the Noise margin is less than the target margin (6) it will send less than 26Mbps down (will do the opposite if you have spare margin) the line, how much less depends on Openreach. Though I don't believe it's active either...

SRA by its nature breaks BT wholesale IP profile system, so for that reason I believe they kept it off, eg user loses sync with dslam, the ppp connection drops, sync is reestablished, ppp logs back in, when ppp logs back in the ip profile is updated.  If SRA is used the PPP stays active and as such the IP profile wont keep up with sync speed changes.  So it be itneresting if BT are planning to change the IP profile system.

For me, I've always been able to achieve more than my IP profile (no bRAS mismatch) so I find it has little relevance within VDSL.

also on the comparison I see they disabled g.lite and t1.413, annexl, finally dynamicF.

You can turn these on/off (mine came with all on but I turned all off apart from VDSL2)

[Chrysalis]

basically thats what I am trying to determine if its actually active or not, if it is the sync speed will move around without disconnections.

ignition pointed out to me on tbb, SRA'd lines dont move above their initial sync speed meaning my issue with the IP profile system is moot if he is right, trying to remember my time on ukonline with SRA I dont think it did go above my starting sync speed, so he may well be right.

[burakkucat]

A picture showing part of the insides of a 288-port Huawei cabinet (currently being installed, November 2013) was recently "slid under the door" of The Cattery, whilst I slept.

I have rotated the image and cropped off all the irrelevances before scaling it to fit within this forum's upload limit.

It appears to show a SmartAX MA5683T.   

Quite a "step up" from the SmartAX MA5616 that Beattie was originally deploying. 

[Chrysalis]

any new ECI pics? I guess its possible the ECI's have changed also.

[burakkucat]

any new ECI pics? I guess its possible the ECI's have changed also.

Sorry Chrys but the ferrets did not leave me anything relating to the ECI cabinets. 

[Chrysalis]

damn, but I think this is good news anyway, it at least shows BT arent sticking to one configuration throughout the rollout.

[kitz]

when was SRA turned on? I not seen any such reports.

It seems to me that BT may be considering this as an option in the near future.  I think I mentioned in another thread a few weeks ago, that in a notice issued to ISPs who where thinking of supplying EU's with their own branded routers, must submit one to BT, who would then perform tests on them to ensure they are suitable to BTs FTTC product.   One of the tests done is SRA.

I dont believe its actually live yet though.  It doesnt harm if the modems are enabled, but it wont work until the dslams are.

SRA by its nature breaks BT wholesale IP profile system,

Yep.  But then again would an SRA enabled line need the DLM?   Certainly not in the complexity of BTs current system it wouldnt. How it would impact on the IP profile is another matter to ponder over.  Wouldnt it be nice if they could make it redundant once all exchanges are 21CN & SRA was employed  (wishful thinking!).

[kitz]

A picture showing part of the insides of a 288-port Huawei cabinet (currently being installed, November 2013)

Thank you b*cat.   
I had heard a rumour that BT were back to installing Huawei cabs on newly enabled exchanges for at least the past month or so. The thought being that they are equipped for vectoring.  Prior to this they had been favouring the ECI's.

I nearly mentioned it in my earlier post, but didnt because I had no proof that this is the case.
By equipped I mean vectoring is possible without any further hardware changes and just requires a config change in the software...  not that its actually in use yet. 

[kitz]

BT cant demand it.

I didnt say they could.  I said if anyone had the weight to get them to change it, then it would be BT... over and above Noddy_ISP.

I dont know for sure and since atm Im more concerned with my own PC and network, Im not going to go searching..  but to make it really simple think of it like a PC that has spare PCI expansion slots. 

It appears the Huawei MA5616, can be upgraded by addition of another module  (so it like adding a PCI GigE network card), but unfortunately the ECI dslams dont appear to have any free "expansion slots" to make it simple to upgrade.

Maybe BT will just do the per card vectoring as "its cheaper", and as such we will not see vectoring at full effeciency.

Ive no idea what they will do.   However theres a difference between vectoring at full efficiency.. and efficient management of line pairs.  Vectoring should work quite well on the line card.  The inefficiency is wasted pairs mapped to the line card.
Mapping may not be such a big concern to some SPs, but to the likes of BToR who own the copper pairs and the dslams.. and retail to other SPs, then it likely will be.   Surely they dont want to periodically have to send an engineer out to jiggle about and physically rewire the ports when theres a device that can do it all electronically.

The above makes me think that BT will most likely upgrade at some point.   Until that point if they employ it on a line card basis only is anyones guess.

I suppose in theory,  theres nothing stopping them rolling it out on the line card.. and then upgrading the dslam when the mapping and use of pairs to ports become in-efficient.  It will also depend on how many lines in the feeder are FTTC.  The ECIs can only handle 64 (per line card).