Kitz Forum
Broadband Related => Broadband Technology => Topic started by: kitz on June 20, 2015, 01:05:42 PM
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Last night I saw a post by AndyH on the PN forums (http://community.plus.net/forum/index.php/topic,139060.16.html).
Credit to him for posting, I think there may be some fact in his statement and some misinterpretation as he's saying
Interestingly, there was a DLM change made on Tuesday to the MTBR threshold. It's basically been halved for all DLM profiles:
Old Threshold New Threshold
Speed 8400 4,200
Standard 16,800 8,400
Stable 33,600 16,800
I have asked for clarification and to check. Whether he will respond or not is another matter because I believe the information should actually be interpreted as
Green Red
Speed 8,400 4,200
Standard 16,800 8,400
Stable 33,600 16,800
This would make far more sense as it brings speed profile nicely in line with the other figures which use half of red for green.
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Reasons why I suspect it should be red/green and someone else has typed old/new above
- Posting one set of 'new' parameters is a bit useless without its opposing pair.
- What is said to be the old thresholds don't appear to be from the last figures we had.
- The new figures are very similar and only speed changed slightly
These were the previous figures that Ive quoted several times on this forum in the past - and theres even a copy of the NGA graphic I posted last year dotted around these forums in a few places and the ones Ive been using for about 10 months for the DLM calculator (http://www.kitz.co.uk/adsl/DLM_calculator.php).
Green Red
8400 4320
16800 8400
33600 16800
Oh and in case anyone doubts me, the Zen training doc also confirms those old figures. I think this may be another example of him getting some good info, yet unfortunately he's put his own interpretation on it and turned it into meaning something else... because those dont appear to be the old thresholds... but green.
All the change has done is brought 'speed' into line with the other profiles in that Red is half of green and now makes 20 resyncs supposedly safe rather than the previous 19.
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What do the changes mean? Aside from bringing speed in line with the other params, it just now means a rounded 20 per day for retrains.
I will change the MTBR RED figure in the DLM calculator but it doesnt make much difference as basically all the parameters are the same as the previous set we had.
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I do wonder over the MTBR figures. To allow 20 a day even on a fast profile seems nuts to me. I wonder who would accept say 10 resyncs a day as possibly OK???. Most people get very upset at a few resyncs a day.
I am with TTB and supposedly on the standard (middle profile) and I am definitely hit when/if I go over 5 resyncs a day. It has happened twice when I have been messing around while thinking it might be 10 a day. For errors the limit is definitely a MTBE of 60 which is consistent with standard. I have got away with 50 and been DLM hit at 70. Maybe TTB has an odd hybrid profile but I suspect not.
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We've discussed about this in the past and I agree with you that 20 doesnt always seem to fit with what we are seeing. Each subsequent release of any MTBR figures always seems to be higher than what can sometimes happen in reality
I think I've also mentioned to you before about the little known or talked about 'Scarlet ILQ' (http://www.kitz.co.uk/adsl/DLM.htm#DLM_profile_changes). I cant find much info about this other than what is on the Plusnet site (http://community.plus.net/library/broadband/broadband-faults-guide-our-testing/) where there is a very hard to see graphic
(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fcommunity.plus.net%2Fwp-content%2Fuploads%2F2013%2F11%2FLine-Quality.jpg&hash=0a8c298528d5b66674882441ccea80cef9d737db)
Note on there the mention of 10. OK things may have changed but what I have found in BT documentation is classification of a 'Very Poor' status (separate from MBTR red) whereby DLM will react quicker if several retrains are detected in a short period. I dont know what is classified as short period, but it leads me to believe that obviously its not over the usual MTBR daily period.
Perhaps it could be something like 10 in an hour (or 2 hours?) for speed, and if they do half things like they usually do for standard then that would equal the 5 you mention you are seeing. Can't find anything about this now and everything is locked down tight since ASSIA case :(
Ive been asked a couple of times in the past week or so if I'd release what info I had got and although Ive always made the page available to members from here, Ive just never linked to it on the main site, because it was specifically the ILQ scarlet and steps to remove DLM where things had come to a halt and these I wasnt sure about.
I think the best thing to do is gloss over those 2 areas, because nothing new has come to light during the past 10 months and it seems stupid holding back on other info such as wide area events etc which I am certain about.
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Kitz how do we know which profile the ISP is using IE: Speed (1) Standard (2) Stable (3) at a guess this line has been moved from Standard to Stable but can't confirm this.
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I dont know what EE are using.
The only ones I know for sure are listed on the bottom of the DLM calculator (http://www.kitz.co.uk/adsl/DLM_calculator.php).
BT is a weird one... because someone said BT will change Speed/Standard upon request. It is possible for the ISP to do that so Im not sure.
jid asked TT (his ISP) which is how we know what they use.
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PS - afaik none of the ISPs are using stable.
Most supposedly use Speed, and TT is the only definite case we have of Standard.
You could try asking them?
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All I can help you with in terms of EE, is that the TalkTalk rep passed on from the FTTC Product Manager that most ISPs use Standard as its the most popular profile, so you could assume you're on that?
Here's the info again for reference to the above fact:
"On Fibre, Openreach owns the DLM. They over several profiles (Speed, Standard, Stable). We use the Standard one as it's the one that delivers the best speeds with a good element of stability. I believe this is the one most used by ISPs but can't confirm what BT Retail uses."
Also this they stated:
CP’s (ISPs) do not have any control over the DLM OR provide for FTTC other than to change the policy (speed/standard/stable).
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@kitz AndyH has responded in his typical manner. ::)
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Here's the info again for reference to the above fact:
"On Fibre, Openreach owns the DLM. They over several profiles (Speed, Standard, Stable). We use the Standard one as it's the one that delivers the best speeds with a good element of stability. I believe this is the one most used by ISPs but can't confirm what BT Retail uses."
Thats good and maybe i was moved from speed on BT to Standard on EE and this is what i seen 1500 errored seconds per day with maybe the odd 2200 on BT for months since DLM reset 13th of FEB once switched over to EE on the 13th of MAY the errored seconds got close to 2000 for one day and the DLM intervened.
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@kitz AndyH has responded in his typical manner. ::)
Yep I saw and responded back.
We know for a fact those figures were in use at an earlier time. The only explanation is sometime between ASSIA/G.inp they changed them, and perhaps it was too high & caused issues, so now they are changing them back again.
@ Les I found this which supports the separate quick succession theory. Its specifically about speed profile so presumably will be halved for Standard
A line would need 10 retrains or more in any rolling 1 hour period to be flagged. This process is independent from the daily DLM process.
Its not linkable Im afraid, but happy to send a screen grab via PM if in doubt... but it doesnt really give any more info than that.
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@ Les I found this which supports the separate quick succession theory. Its specifically about speed profile so presumably will be halved for Standard
A line would need 10 retrains or more in any rolling 1 hour period to be flagged. This process is independent from the daily DLM process.
That would be sufficient to explain my events. I will assume it is true ----- as testing the DLM can require more than my patience before normality returns.
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SO kitz, in laymans terms what does this mean for us, the end user? :)
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SO kitz, in laymans terms what does this mean for us, the end user? :)
Not a lot really, just that if you are on 'speed' profile then the system should be able to cope with a full 20 resyncs per day without kicking in.
There still is the scarlet (very poor) process though which looks for 10 syncs within an hour (speed). Im afraid I dont know what it is for standard.
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Thanks for the explanation :)
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Sorry if the above reply was a bit blase. I'm not exactly quite sure what happened, but we knew what the limits were. These were posted in a couple of places including the Zen training doc. Then sometime around the ASSIA case last year, it became extremely difficult to find out anymore information and since then we dont know if anything has changed. We know for a fact that they they did some twiddling of DLM around that time but what it was afaik hasnt ever been disclosed what they did.
From what AndyH has posted, I can only assume - and its the only logical reason I can think of - that sometime between then and G.INP they reduced the MBTR and now we know theyve put it back again and using practically the same figures, because it appears to have been too low and catching too many people.
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In response to the remarks on another forum about 'cockroaches' and click through.
The site cannot use any form of shared/cloud hosting. No host will touch me for any service other than dedicated. Its my choice to use UK hosting as I dont want crappy overseas hosting and I need decent 24/7 support. Check out how much that costs.
I'm well aware I could do more on the ad side but I deliberately try and keep any ads to a minimum. I dont use tower scraper ads which are the most profitable and most tech users use ABP anyhow. This site is non-profit making and there has been many a time when I've funded from own pocket, and times when Ive had to borrow from a friend to cover hosting costs. Another personal friend who has nothing to do with the site always donates to hosting costs
I'm thinking deleting the 'shop' as only once has it generated any income. There's a clear record on the site of donations and in response to 'click through' those defamatory words are treated with the contempt it deserves.
You try balance the books with this income - Ad generation income for the past 7 days. I think that makes it a long way off being a click through for profit site. It doesnt even begin to cover hosting. :(
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ETA
Im removing image as this post was originally made before I'd twigged what the cockroach reference was all about. Don't see why I should have to justify for something that I hadn't said or post site stats. Enough people have viewed it already anyhow to verify that that aim of this site isnt for profit.
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[Further info added ]
I just noticed that webif's post has been changed and everything has now become clearer. TBH from his first posting I thought it was him making a reference to someone on this forum.
I 100% didn't even have the slightest clue from his first post what the reference to cockroaches was on about. I viewed via mobile last night and hadn't s even seen the post by someone else. I'd responded straight to Mark & then my response came up on was on top of another page so I'd totally missed that post and why it never twigged what webif or anyone else's reference to cockroaches meant. Even at the time of making my post above I still didn't know what he was on about.
Said post has now been removed. (which now takes my post last night to the bottom of the page in position of the deleted one). It was NOT anything that I had said like the quote may give the impression of. It should be clear from my first reply to Mark that I was hurrying last night and I didnt have time to explain further until today which is precisely why I'd used the reference blase - because I knew my reply to him last night was in haste.
That post has not been removed now because of any threats - I genuinely had not seen it until it was brought to my attention a few moments ago.
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kitz I have no idea what you on about.
if others elsewhere are trying to slander your site dont stress too much over it, none of us will leave because of it.
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I'm not sure what's been said but this is and hopefully will always be my first port of call for help/advice/news. I used to run forums myself Newnetter/Metronetter and appreciate how much it costs first-hand when it's coming out of your own pocket. If I could afford to donate (current employment status restricts) I would gladly.
Your doing a great job so don't let some moron tell you otherwise Kitz.
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Also not really sure what's happened, but as above kitz you're doing a great job, keep it up we all appreciate it! :)
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>>> Also not really sure what's happened
Someone calling this site a click through. By displaying the most minimal ads I can, hardly makes it that - TBB shows way more ads and much larger ads than I do. Is he going to make the same accusation against them too.
and also the suggestion "desperately want to be part of a circle" is laughable.
Im not even sure what circle that is supposed to be, because its only certain people within ISPs and one other that appears to have access to the ISPforum. :-X
My info comes from elsewhere within BT and other places such as SINET. I have my own contacts in BTw but just dont pester them or abuse that privilege and I know for a fact that the site is well respected within BT. In fact I recently had a long personal one-to-one with someone very high up in Openreach who should know what is going on and far more aware of matters such as g.inp than the ISPForum. I may not have anything in writing, but we weren't wrong.
Just because my info doesn't come from the ISPForum or certain others dont get the same info as me, isnt my fault. BT don't release all info to ISPs and other depts perhaps dont get some info that the ISP does. It most does not give certain people on another forum the right to talk down to me and diss any info that comes from here.
OK so Im not part of this mythical circle, but I'm happy with the way things are, knowing that BT are well aware of what we do and respected enough to take note if there is a serious issue. By being outside of the circle means that I dont have to say black is white when I can clearly see that perhaps something is grey. I will respect things told in confidence and if there's things they don't want disclosing for obvious reasons, but OTOH I will also continue to dig for information so that EU's can continue to 'self help' which is the whole aim of the site.
Time is often a limitation with me, because I cant sit here 24/7 posting, still do admin, site upgrades, tutorials and a million other things.
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its the boys club, BT have the weirdest NDA setup ever if what ignition said is true, apparently bog standard things that should be reported to end users are all NDA O_o Also why hasnt revk been cutoff for I guess breaching the NDA everytime he gets annoyed with BT.
It seems more likely that those working for these isp's seem to enjoy witholding the information and do it for that reason instead.
Whats commercially sensitive about telling end users if a problem will be fixed or not.
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@ npr if you're reading - which I think you do. I've been tied up mad busy the past few days and hence not going over to t'other place to respond. I went tonight to see what was happening with the speeds and just read today's events. Unfortunately both threads are now locked so I cant respond.. but you may be interested in this because you asked.
BT Retail users are on their own BT Wholesale/21CN core network (WBC). I can't recall users on their forums reporting issues like this and at the same time, the Plusnet/BT Retail networks can't be compared as they really are separate.
Plusnet use a network shared with other service providers that use BT Wholesale and the same service (WBMC Shared).
The issue with the variable throughput that has been noted on here and can be solved (albeit sometimes temporarily) by gateway hopping, appears to be exclusive to Plusnet. Given the size of Plusnet and the number of customers they have, I imagine parts of the WBMC Shared network have been specifically designed and built solely for Plusnet. There are also the host links (these connect Plusnet's network to that of the BT Wholesale WBMC shared network) which Plusnet buy for their own use from BT Wholesale.
So you're saying BT broadband uses a different backhaul to the one BTW provide for Plusnets. Shocked Shocked
I was hoping I could avoid moving to BT internet or sky, is there any other choices which escapes this issue?
BTr most certainly does not use WBC - it uses WBMC.
I'm also pretty certain that other ISPs would be extremely unhappy if there was any inkling of the WBMC network being designed for or built for Plusnet. :o Cue OFCOM and unfair advantage. This is aside from the fact that the way shared WBMC is built then all ISPs using that platform have equivalence. BTw do have to plan though for capacity on their MSILs and I suppose there could be an issue if there is a sudden surge of Plusnet customers say migrating from ISPs which arent shared WMBC. I mentioned months ago (http://[url=http://community.plus.net/forum/index.php/topic,135389.msg1209653.html#msg1209653) that if PN were insisting that it wasnt their host links, then by process of elimination it was most likely the shared MSILs.
If you are wanting to stay away from the BT core, then your alternatives are WBC providers such as Enta/Daisy resellers who I believe use Murphx for their core routing. Theres also AAISP who offer some accounts using TTB routing.
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WBC (http://www.kitz.co.uk/adsl/wbc_wbmc.htm#WBC_EU_Products) is when the ISP offloads at the Interconnects (http://www.kitz.co.uk/adsl/wbc_wbmc.htm#WBC_Interconnects) and their EU traffic never enters the BTw core network previously known as Colossus. WBC the 21CN equivalent of the old DataStream.
Dedicated WBMC (http://www.kitz.co.uk/adsl/wbc_wbmc.htm#WBMC_dedicated) is when the ISP is responsible for purchasing its own bandwidth at the MSILs but still use the BT wholesale core network for backbone transit. The fact that you can see the core nodes on a BTr tracert is proof that they use WBMC.
afaik BTr is the only ISP that uses dedicated WBMC. I cant think of any who were big enough to make it economical - Plusnet maybe but they are already too heavily invested in their host links and Junipers to ditch shared WBMC. Perhaps in future if they do a complete overhaul of the network and ditch the current invested equipment running into £millions. Dedicated WBMC was introduced to replace the old 'RIN' network. The whole idea of WBMC was to ensure equivalence, yet allow some flexibility.
Shared WBMC (http://www.kitz.co.uk/adsl/wbc_wbmc.htm#WBMC_shared) is when the ISP leaves the control of MSILs bandwidth up to BTwholesale. Its precisely that - shared so if there were issues then it should affect all customers equally. The design of WBMC means that the routing is from the particular exchange so it doesnt make any difference which ISP uses it. Shared WBMC is the 21CN equivalent of IPStream. Things only get different depending on where the ISP chooses to have their host link(s). I saw a video not very long ago presented by RevK saying that there were issues in the BTw network causing congestion. Its a recent video - ie weeks not months ago.
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Thanks for the guidance kitz.
My contract with PN has another 6 months so I've lots of time to gather this info and try to understand it and the implications before I need make the decision of where to go next.
The main reason I'm looking for a new provider is not the current issue, it's the way they handled my support ticket. I used to have a great deal of regard for PN's support but I'm afraid the way they've handled this ticket has destroyed that regard.
The reason I was trying to avoid BT internet is that I once used them in the dark days of dialup -- need I say more ;)
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Unfortunately the lack of input from the reps hasn't been ideal and helped diffuse the situation. :(
I've been on a few mammoth gate hopping sessions in the past and it is weird how sometimes it can take so long to find a decent speed again, then you can end up on the same gateway and all is well again. Because we can't tell which endpoint then it's hard to identify if it's those or the MSILs. Because of the length of time it's been going on and the fact that once I do get on a decent pipe and it's stays like like for ages, I am more suspicious now that it may not be the end points but something to do with my routing between RAS and the pn endpoint.
The video of revK, he actually said something like See there is conjestion even if BT can't see it.
ps - yes also been there with BT. I was served final notice of excessive online time. Luckily it was about 3 weeks before the exchange went live for adsl. I was doing my dissertation at the time and also one of the BB4campaigners so really struggling to keep the hours to their limit :(
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@ npr if you're reading - which I think you do. I've been tied up mad busy the past few days and hence not going over to t'other place to respond. I went tonight to see what was happening with the speeds and just read today's events. Unfortunately both threads are now locked so I cant respond.. but you may be interested in this because you asked.
BT Retail users are on their own BT Wholesale/21CN core network (WBC). I can't recall users on their forums reporting issues like this and at the same time, the Plusnet/BT Retail networks can't be compared as they really are separate.
Plusnet use a network shared with other service providers that use BT Wholesale and the same service (WBMC Shared).
The issue with the variable throughput that has been noted on here and can be solved (albeit sometimes temporarily) by gateway hopping, appears to be exclusive to Plusnet. Given the size of Plusnet and the number of customers they have, I imagine parts of the WBMC Shared network have been specifically designed and built solely for Plusnet. There are also the host links (these connect Plusnet's network to that of the BT Wholesale WBMC shared network) which Plusnet buy for their own use from BT Wholesale.
So you're saying BT broadband uses a different backhaul to the one BTW provide for Plusnets. Shocked Shocked
I was hoping I could avoid moving to BT internet or sky, is there any other choices which escapes this issue?
BTr most certainly does not use WBC - it uses WBMC.
I'm also pretty certain that other ISPs would be extremely unhappy if there was any inkling of the WBMC network being designed for or built for Plusnet. :o Cue OFCOM and unfair advantage. This is aside from the fact that the way shared WBMC is built then all ISPs using that platform have equivalence. BTw do have to plan though for capacity on their MSILs and I suppose there could be an issue if there is a sudden surge of Plusnet customers say migrating from ISPs which arent shared WMBC. I mentioned months ago (http://[url=http://community.plus.net/forum/index.php/topic,135389.msg1209653.html#msg1209653) that if PN were insisting that it wasnt their host links, then by process of elimination it was most likely the shared MSILs.
If you are wanting to stay away from the BT core, then your alternatives are WBC providers such as Enta/Daisy resellers who I believe use Murphx for their core routing. Theres also AAISP who offer some accounts using TTB routing.
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WBC (http://www.kitz.co.uk/adsl/wbc_wbmc.htm#WBC_EU_Products) is when the ISP offloads at the Interconnects (http://www.kitz.co.uk/adsl/wbc_wbmc.htm#WBC_Interconnects) and their EU traffic never enters the BTw core network previously known as Colossus. WBC the 21CN equivalent of the old DataStream.
Dedicated WBMC (http://www.kitz.co.uk/adsl/wbc_wbmc.htm#WBMC_dedicated) is when the ISP is responsible for purchasing its own bandwidth at the MSILs but still use the BT wholesale core network for backbone transit. The fact that you can see the core nodes on a BTr tracert is proof that they use WBMC.
afaik BTr is the only ISP that uses dedicated WBMC. I cant think of any who were big enough to make it economical - Plusnet maybe but they are already too heavily invested in their host links and Junipers to ditch shared WBMC. Perhaps in future if they do a complete overhaul of the network and ditch the current invested equipment running into £millions. Dedicated WBMC was introduced to replace the old 'RIN' network. The whole idea of WBMC was to ensure equivalence, yet allow some flexibility.
Shared WBMC (http://www.kitz.co.uk/adsl/wbc_wbmc.htm#WBMC_shared) is when the ISP leaves the control of MSILs bandwidth up to BTwholesale. Its precisely that - shared so if there were issues then it should affect all customers equally. The design of WBMC means that the routing is from the particular exchange so it doesnt make any difference which ISP uses it. Shared WBMC is the 21CN equivalent of IPStream. Things only get different depending on where the ISP chooses to have their host link(s). I saw a video not very long ago presented by RevK saying that there were issues in the BTw network causing congestion. Its a recent video - ie weeks not months ago.
kitz I just had a thought
Think how the government outsources tasks which makes requests under the freedom of information act get rejected due to commercial sensitivity.
It could well be that BT built the WBC network just for plusnet, and as a bonus it complies with what ofcom ask for in terms of wholesaling, BT retail use a different network for its own customers. But because this WBC network is not operated by plusnet, it allows plusnet to say to their customers we are powerless and we cannot do anything, simply because BTw is a different company on paper and claiming commercial confidentially. Very convenient for them.
Meanwhile the BT group cost cutting continues as plusnet have now scrapped 24/7 uk support and are arrogant enough to not even bothering informing customers thinking they will get away with it.
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I'm not at the PC so this will be short as takes me too long to type.
Plusnet don't use WBC, they transport via the core so it has to be WBMC. I'm not quite sure what you mean about build a different network.
It's all meshed and you could end up getting different pipes within the core so to speak. There is the possibility and more flexibility with dedicated WBMC but with shared, I don't see the point of separate network, yes they could prioritise certain ISPs if you wanted to get into the realms of conspiracy, but if something like that ever came to light it would be massive and I don't think they'd risk it. The whole design of 21CN was supposedly for equivalence, and that so no SP could be favoured over any other.
Re pn support - I've been out all day and didn't see that. This is bad and topic for another thread :(