Kitz Forum
Announcements => News Articles => Topic started by: UncleUB on September 28, 2009, 10:40:00 AM
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But this still means that those on long lines will still see no benefit from this.
Its a case once again of those that have will have more and those on long lines will be left further behind and paying the same for (in some cases only getting 512kbps) than those getting over 20MB.
http://www.thinkbroadband.com/news/4056-bt-pledge-24meg-to-75-of-the-country-by-2011.html
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Having had some experience (since 1 May) of this 21CN, I think BT must be living in cloud cuckoo land to think that the current product offering is going to be accepted by the masses. I can tell you all that there are a lot of 'not very happy bunnies' on the Plusnet trial. I've now got to the stage where I've asked to be taken off the trial, and I am sure there will be many others who follow.
toulouse
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One other point announced today is that BT Wholesale will be dropping prices to communications providers from January 2010 which should reduce costs to end users. The plan is to decrease bandwidth charges by 50% and also to introduce a reduction in WBC rental costs. This should mean that providers can offer lower prices and will be more willing to bundle more bandwidth with services. This will be particularly useful with new websites tending to be more bandwidth intensive and with streaming video becoming ever more popular.
I found that more interesting but what is it?
Goverment are going to tax phone lines to improve broadband but Openreach are reducing the rental costs!!
Looks like bandwith allowances will be increasing I was wondering when something would give.
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Having had some experience (since 1 May) of this 21CN, I think BT must be living in cloud cuckoo land to think that the current product offering is going to be accepted by the masses.
I wonder where it's falling down.
From the little I've seen of it all it would appear to me part of the problem is the new DSLAM/MSAN hardware/software, and the potential incompatibilities with current modems.
Also, and this is something I've experienced myself, it's very possible that lines with slight faults/many joints/aluminium which just about function with standard ADSL (G.DMT) experience an exacerbation of issues when using more of the frequency spectrum/higher speeds, with increased chance of crosstalk and more spectrum that is susceptible to interference.
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@orainsear - you may well have something there about 'slight faults', etc. I'm fairly sure that a good part of my line to the local exchange is semi permanently water logged, but how do I prove that ? Before I joined Plusnets trial I had been with them since June 2007, and had only ever connected at 8128/448. When I went onto the trial, for the first 6-7 weeks I saw speeds of upwards of 11939(d) with SNR of around 6-7db. Something (strange) happened overnight 23/24 June and it's been completely bizarre ever since. The new 21CN DLM would only allow my line to run with an SNR of 15, even after intervention by BT engineers and Plusnet support staff, so there came a time last week when I decided that I'd had enough. They're now moving me back to the ADSL Max product to take effect this coming Friday.
TTFN
toulouse
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>> But this still means that those on long lines will still see no benefit from this.
Unfortunately not... until FTTC/VDSL is rolled out, then those long lines arent going to see any improvement.
Certain LLU ISPs (such as Be) have been doing adsl2+ for a long time now.. they dont have the same massive problems as BT 21CN seems to be having.
I cant quite see where the problem lies.. theres been mention of router/MSAN incompatibilities.. but TBH that doesnt sit quite right with me.
After all they are supposedly using Fujitsu GeoStreams and Huawei MSANs.
Theres been Fujitsu Geostreams in some exchanges for years already... and lots of other LLU ISPs already use Huawei MSANs (TT/Tiscali etc).. so why should BT be saying theres a compatibility issue between MSAN and router when TT doesnt seem to be having the same problems.
I dunno.. but one of the major differences between the LLU operators and BT Wholesale systems is BTs DLM and the IP/bRAS profiling. If they admitted there was a problem with their DLM system on adsl2+ then Id be more likely to understand.
>>> The new 21CN DLM would only allow my line to run with an SNR of 15, even after intervention by BT engineers and Plusnet support staff, so there came a time last week when I decided that I'd had enough.
.. and there we go.. the BTw DLM kicked in limiting the line.
The vast majority of complaints I have seen seem to involve the DLM doing something silly and or being over sensitive.
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Hi
quote They're now moving me back to the ADSL Max product to take effect this coming Friday.
Good luck hope they haven't messed that up for you :no:
Regards Jeff
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kitz said .....and there we go.. the BTw DLM kicked in limiting the line
I think they must be feeding that DLM system a daily dose of crack cocaine - it certainly seems to have lost the plot !!!!
and jeffbb said.... Good luck hope they haven't messed that up for you
I don't think for 1 minute that the problems that I and many others had on the trial were down to Plusnet, they have been very helpful in trying to resolve the problems....but there comes a time when enough is enough
If the switch back to ADSL Max doesn't go smoothly I will be moving over to a LLU provider. I have a choice of a couple on my exchange, but I've got to say I do like the Plusnet service, so will stick with it for now.
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>>> so why should BT be saying theres a compatibility issue between MSAN and router when TT doesnt seem to be having the same problems
TT and Tiscali provide customers with Huawei modem routers - maybe they know something :-\ Then again it's probably just been part of a mega bundle deal to provide them with MSAN hardware and user end equipment.
The DLM system is a good idea and you can understand the thinking behind it, however there just seem to be so many situations where things don't work as they should with ADSL Max that the 21CN working properly seems like a pipe dream.
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>> TT and Tiscali provide customers with Huawei modem routers - maybe they know something
TT supply Huawei modems,
but Tiscali dont.. iirc the latest is TG585v7 or the Siemens Gigaset SE587 (http://www.kitz.co.uk/adsl/frogstats.php#55).
Tiscali have also been wholesaling LLU for years and I dont think any of the ISPs using their services ship out Huawei routers.
>> The DLM system is a good idea and you can understand the thinking behind it, however there just seem to be so many situations where things don't work as they should with ADSL Max that the 21CN working properly seems like a pipe dream.
yep... afterall dslMax also had horrendous teething problems and stuck profiles etc. It still has some odd quirkyness, so its no wonder its not quite right yet on 21CN. :(
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but Tiscali dont.. iirc the latest is TG585v7 or the Siemens Gigaset SE587 (http://www.kitz.co.uk/adsl/frogstats.php#55).
:lol: I got told by tiscali tech support earlier that the 587 was "one of the most successful routers on the market :lol:
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Hi,
I was switched from "up to 8 Mbps" to "up to 24 Mbps" a few months back.
Now it's settled down I usually achieve about 5 Mbps, about .5 Mbps faster than the "up to 8 Mbps" service.
If I'm typical, then investing in 24Mb infrastructure is a waste of money.
5Mb is usually fine for my current needs, but I do see big variations in achieved speed from day-to-day.
I do feel short-changed in that I'm not getting what the service promises.
My ISP tells me with Line Attenuation Down of 37.5 dB I should get much faster. Maybe I'll changed to Be/LLU.
Cheers,
Peter
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Hi geep,
You'll see that Kitz estimates you should get 10656 kbps with an attenuation of 37.5 and that falls in nicely with Zen's real word speed estimates of 9 to 13 mbps you'll find written on their site. Any suggestion that the population on average is going to get anywhere near 20mbps is in the cloud cuckoo land of marketeers and certainly not real practioners !
Kind regards,
Walter
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@waltergmw,
yes cloud cuckoo land indeed - I was actually told (unofficially) by a member of Plusnet support staff, that to be able to achieve speeds of 20Mbps you would actually have to live in the exchange, and while some of the buildings are quite large I don't think that's gonna fly.
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I know of a 39dB line that should in theory go much faster than it did.
It was fine at 8128 for many months until after one episode when the DLM kicked in.. and then it was a downwards spiral.
Despite requests for resets etc, the DLM would for ever after kick in at the slightest thing resulting in sync speeds of around 5/6Mb as normal.
Getting totally fed up of the BT IPprofiling + DLM... which seemed to be the main problem.. the line was migrated to Be LLU.. where it now happily sits at around 10Mb on a 3dB profile.
I know why the DLM is supposed to be there... but when it starts misbehaving it can be a real PITA.
I myself have had lots of problems with the IPprofiling system in the past which have had me tearing my hair out... and thats on a very good line.
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I was actually told (unofficially) by a member of Plusnet support staff, that to be able to achieve speeds of 20Mbps you would actually have to live in the exchange, and while some of the buildings are quite large I don't think that's gonna fly.
Deterioration of the line can also have an impact, and theres nothing in place to ensure that a line is maintained to a certain standard so the line is optimised for adsl.
I myself am one of those that could be classed as 'living in the exchange'. In theory I should easily be able to get 24Mb.. and for a while I did, but my line has slowly deteriorated over the past year to 21.5Mb... and thats with just a 3dB margin.
OK I do appreciate Im lucky to be able to get the higher speeds.. But Im less than 200m from the exchange and to see a deterioration of 2.5Mb is still a hefty chunk.. and my line is vastly under-performing.
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Really the Nation doesn't deserve a bald Kitz !!!!!!!!!!!!!!
Walter
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Here is my thoughts on BT's adsl2+ rollout. I have a long line on ukonline's LLU service.
BT utilise dynamic line management (DLM) the aim is to keep their support costs down by automating line settings to deal with noise/interference on the line. My own experience of this was it either didnt react when required or was too sensitive. DLM potentially could have been good but the major flaws with it I see were the fact it could not be turned off and BT would not easily reset profiles back to 6db. On 21CN (adsl2+) I expected DLM to stay but a better version of it that was improved based on BT learning from the problems on their adsl max service, the reality was they seemed to copy from sky's poor DLM and the new version is over agressive in reducing synch speed. Again like the old version isp's cannot overide it they can only adjust the algorithm used.
BT also utilise BRAS IP profiling, this in effect caps line speed to a specific level, ideally just below the synch speed. The problem with this is the steps between the profiles are too large and that it takes far too long to recover to higher profiles following a low synch. BT again did not learn from their adsl1 experience and have a horrid BRAS profiling system for adsl2+. In addition we have no real explanation as to why the system even exists, the excuse was on adsl max it was required because of the ATM backhaul, however BT now utilise a IP backhaul the same as the LLU isp's but have persisted with the BRAS profile system. My hatred for it stems from the fact I have a line that would resynch in the morning (due to working hour noise bursts) and again at night resulting in what was in affect a 2 tier line, the BRAS profile requiring a 3/5 day wait couldnt keep up and as such when I synched high like in the weekend day times I couldnt fully utilise my line due to a low BRAS profile, basically when I synched high it was rarely in excess of 3/5 days.
So why am I better off on ukonline LLU?
1 - No DLM, manual line management is how I want it, by luck the default line settings were decent for me, 7db and fast path on adsl1. Now I am on 6db and fast path on adsl2. (not adsl2+).
2 - No BRAS profiling, my line is stable but it does mean if I do have a sudden change of speed such as when doing stuff on my router or during noise bursts (see later) then I immediatly get my speed back when synch speed recovers.
3 - SRA, (seamless rate adaptation). A brilliant improvement in adsl2/+ that is a godsend for long/noisy lines. Basically does what DLM was aiming to do but do it properly. The synch speed will adapt to line conditions without dropping connectivity, it can move the synch speed downwards or upwards. This allows a line to synch agressively knowing that if noise occurs the line will adapt and synch will remain stable. The downside of SRA is it seems to be sensitive to router/firmware compatability with the dslam chipset to work properly, I have no idea why BTw are not even attempting to utilise SRA.
To give you an idea of how my line has performed on BTw and ukonline is as follows.
On BTw the few weeks before I moved to LLU I was typically synching at around 5700kbit with a 9db profile on fast path, I would need to manually resynch every 1-5 days tho due to excessive line errors creeping in when bitswapping broke. I experimented with interleaving which boosted the synch to around 7000kbit but was less stable than fast path, not fully sure why but I think the higher synch was probably part of it. Bitswapping appeared to work far better on fast path.
After my move to ukonline all noise bursts that were occuring immediatly stopped, this obviously helped a lot. On adsl1 for a while I was sustaining around 5600-6000kbit for a week or 2 at a time. Eventually I volunteered for a adsl2 fast path trial and got myself the router to go with it so I could utilise SRA. This completely transformed my line allowing me to have a aggressive synch and keep stability.
Now in optimal conditions I can synch over 7300kbit and in poor conditions (like in middle of night) at around 6000kbit, SRA will hover the synch between these points, the synch will stay up for weeks/months through thunder storms etc. no problem. Recently I have started getting noise bursts again but SRA also deals with it fine.
In summary I agree with kitz DLM/PROFILING is whats murdering BT, they persist with auto,ated systems and tech support who refuse to acknowledge faults is dragging people to LLU in droves.