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[jelv]

Interesting (if correct).


My bold:

Who should I happen to bump into today on my way to the post office but a BT Engineer working on my FTTC Cab.
I have had major problems with my fibre broadband over the last few months and after all of the tickets raised and OpenReach engineer visit my broadband is still in the toilet, the only replies I have had from PlusNet are "WE HAVE TESTED YOUR LINE AND FOUND NO PROBLEMS" & "YOU ARE WITHIN ESTIMATES"
I spoke to the BT guy working on the cab and asked him politely what he was up to, he replied just fixing a few issues because of some below standard wiring, I told him I had a few problems with my broadband and I am connected to the cab he was working on and could he check my connection to which he replied you will have to raise it as a fault before I can look into it. he then asked what kind of problems and I replied I've dropped from 65Mbs to around 45Mbs and it hasn't changed for months, like I've been capped or DLM isn't working.
He said yes probably heat as effected the DSLAM and DLM is holding you at 50Mbs band which is a know issue with ECI Cabs because of the compact size, very little space inside and poor ventilation.
Not much I can do about that he said, BT should never have implemented ECI cabs but they are cheap and save BT money and look better than the larger Huawei cabs.
Interesting stuff ?

New link: - here.

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Admin: Added new link.   Original link appears to have moved and no longer works.

[burakkucat]

Interesting, indeed. Especially as we have heard, previously, from a very reliable source that ECI cabinets had been retro-fitted with heating pads to stop the condensation forming on the M41's back-planes.

How to distinguish between a cabinet equipped with an ECI Hi-FOCuS M41 and a cabinet equipped with an Huawei SmartAX MA5616 -- the ECI equipped cabinet has many more ventilation slots in its (front) door than the Huawei equipped cabinets.

[Chrysalis]

ECI for the win Great company, best dslams in the world

[ejs]

If that's true, the only way I can think of for an overheating (or overheated) cabinet to result in permanently lower speed would be if the heat has damaged or degraded some components, but it doesn't seem likely that that would have been allowed to happen. ECI cabinets are supposed to contain a variable speed fan, and I can't imagine the temperature in the cabinet wouldn't be monitored.

I don't want to try to work out how much of the cabinet's total power usage actually goes into the VDSL2 signal transmitted down the lines, but I don't expect it to be significant compared to all the processing involved, so I expect that reducing the power of the VDSL2 signals transmitted down the lines, which would result in lower speeds, probably wouldn't have a significant effect on the power consumption and temperature of the cabinet.

[niemand]

If the DSLAM is hot enough to cause damage it will be alarming and probably shutting itself down to protect itself.

Seems a tad far-fetched.

[kitz]

hmmm quite a few things that dont ring true.

BT should never have implemented ECI cabs

BT have ALWAYS used at least 2 suppliers of systems for their kit going back to the year dot.   The Huaweis fell a bit out of favour in 2012 when there was some big scare or other about spyware (USA refused to use them) and hence most cabs installed in 2013 were ECI's.

but they are cheap and save BT money

I'm pretty certain that I read something years ago that the ECI DSLAMs were more expensive out of the brands! 
This was back in the days before any talk of vectoring or G.INP - which is when it began to fall out of favour in certain communities.  Believe it or not ECI and the Lantiq chip was supposedly cutting edge and ECI were the pioneers when it came to some technologies.  Just a shame that BT chose the M41 rather than the V41.   ECI cabs are I believe used by several other countries, yet its only really in the UK that you seem to hear people moaning about them.

and look better than the larger Huawei cabs.

Ummm...    Wasnt it more to do with supply & demand and no of premises passed as to which type of cab was used?
Thats rubbish because there are several thousand Huawei MA5616T cabs installed in the UK which is of similar size to the ECI. No way is a centimetre or two going to make any difference to a passer by. 
 

poor ventilation.

As b*cat has already pointed out, the ECI's have more vents than the similar sized Huawei cabs. They were supposedly too well ventilated and suffered with condensation.  Heat pads had to be installed in them for use when the temperatures dropped.

They’ll automatically turn on when the ambient temperature within the DSLAM reaches less than 10 degrees Celsius. The heat will make sure that the temperature doesn’t drop too low and will prevent the electronics from degrading due to condensation. - link

heat as effected the DSLAM

Over heating would cause shutdown, the temp in the cabs are monitored. Any degraded components would be replaced.  Im with ejs the only way would be to cut back power for all lines, and Im not sure if this would actually help.  Would this also have an effect on such things as PBO and PSD masks?

Also Im quite sure some of the more observant on MDWS would notice if this was happening with their eci cab.

DLM is holding you at 50Mbs band

I dont know the line, but far more likely:-
1) Any suddenly speed loss would likely be attributable to cross-talk.  Ive so far 'lost' 32/33 Mbps to cross-talk.
2) Could have a 'stuck cap' which we have seen across all types of cab

Seems a tad far-fetched.

Just a bit! 

[GigabitEthernet]

I've never seen an ECI cab in the wild.

[kitz]

There's lots of them around here.    See pic below for one near me, which is interesting because its near a Huawei MA5616 which was installed last year.  The M41 has been there since 2013.

A lot seems to depend on when FTTC was installed.    Late 2012 to 2014 was when they were the most commonly used.

[Chrysalis]

I had never heard of ECI before BT started using them, never mentioned in any research documents either except recent ones where they mentioned in a bad light.

BT's dual vendor policy creates a two tier service, but it could have been implemented better, they should have chosen two vendors who both used broadcom so there was common behaviour.

I remember back in the adsl max days BT used texus instruments and I think the second vendor was fujitsu, after I moved to aaisp they were trying to tackle my really unstable line and I remember shaun mentioning to me I am on the poor quality vendor chipset, he ordered a lift and shift which put me on a TI dslam, it didnt magically fix my problems but there was a visible improvement in both sync speed and stability.  The most noticeable affect it had was that bitswapping started working properly which it wasnt on the other vendor.

kitz you are the first person I seen anywhere at all to claim the ECI's are more expensive, there was even a BT shareholder document that mentioned that the ECI contract allowed them to expand the rollout due to more favourable costs.  The view I take is BT moved to ECI after about 1/3 of the rollout with the aim of reducing costs, but then when the decision was made they were to consider vectoring the focus got shifted back to hauwei for the final third, I was not the only one to notice this timing.

[GigabitEthernet]

Most of the area I tend to frequent is BDUK hence why!

[kitz]

Much of the info on ECI's site has now disappeared, but iirc they were the first vendor to work on system level vectoring and offer a DSLAM with this capability.  Other countries teleco's appeared to favour them and they have a long history in telcoms, its just that we never really heard much of them in the UK.... and for some reason BT seemed to move away from the likes of Marconi.
In 2012/2013 , general consensus was that the ECI was better than the Huawei's - eg link

Public opinion went downhill when people realised the M41's wouldn't support system level vectoring.   Surely that is Openreach's fault for not having the foresight to pay a few quid extra and purchase V41's?

Re cheaper.   This is the debate at the time when the US gov got itchy feet over Huawei and barred them. 

You couldn't make it up! And we'd be left with a total monopoly of DSLAM kit supplied by ECI of... Israel! The ECI kit is considerably more expensive, which could only delay FTTC roll-out further.

Opinion on the ECI's back in 2012 which is when BT bought them was a lot different than it is now.


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ETA

I just had a thought...  although the ECI cabs were supposedly more expensive, I wonder if they were considered more economical due to the fact they had 64 port line cards. A previous limitation of the Huawei's was only 48 ports per line card.