Sync speed / IP profile

Apoloogies if this is a daft question, or has already been asked before - but just noticed something interesting on my Infinity 2 connection via : sync speed is 75.9 but ip profile is 73.46. I thought ip profile controlled download speeds? Or am I talking about completely different things.
Many thanks.
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They both control speed in different ways.
The sync speed is the speed of the low level connection between the cabinet and the (white Openreach) modem. That is determined by the cab and the modem, based on the rules of Digital Line Management (DLM).
The ip profile is a limit imposed at the exchange (or somewhere near there) on the higher level (PPPoE) connection between the exchange and the (black HomeHub) router. The idea of the IP profile is to prevent your data being sent from the exchange to the cabinet faster than the cabinet can pass it on to you. The IP profile is automatically set from the sync speed whenever a high level connection is reestablished. It is set to a value just below the sync speed (around 96.8%), to allow for certain overheads. The actual download speed will be at best a little less still because of yet more overheads.
The sync speed is automatically adjusted when the low level connection breaks, or when DLM decides to give you slightly more or less speed (usually in the middle of the night to limit disruption). Often a break in the low level connection forces a break in the high level connection, and so the IP profile is automatically reset when the the low level sync is reestablished. Quite often the high level connection is not broken and continues despite the new sync speed. This results in a 'stale' IP profile. If the new sync speed is lower, you will only get the lower speed as that is all the line can (for the time being) manage. If the new sync speed is higher, you won't get the benefit as the IP profile will act as a throttle. For that reason we often suggest people disconnect and reconnect the ROUTER (NOT the modem) each morning if they suspect there might be changes; to force a profile reset. If you have an unlocked modem (as you must have) and can see the sync speed, then you can tell more exactly when a mismatch has happened and thus whether such a disconnect/reconnect is needed
You will see from your figures that the IP profile is correctly set for the sync speed.

Similar Messages

I think my sync speed is stuck or been capped

Hi everyone, last week i had a full line reset because i started dropping in speed, from 16meg al the way down to 9meg, at the time time of the reset my sync speed went to 12.5meg, 24 hours later i was down to 9.494meg down and 1.12 up, im supposed to be on another 10day training but nothing has happened, meaning the hhb3 hasnt switched off or resynced since i dropped to 9.4meg, now after 5 days of constant connection there was still no change so i did a something to try and make my speed drop but nothing happened, it still synced at the exact same speed 9.4meg, im certainly not rate adaptive and i cant have any line issues or my speed would of dropped after constantly plugging in and out the socket and making it resync, so the only things i can come up with is that ive either been capped or the exchange has got stuck for some reason, ive even gone through my entire extension wiring and changed it to cat6, it made my line attenuation lower but no change in sync rate heres my speed test and hub stats.
ADSL Line Status
Connection Information
Line state:
Connected
Connection time:
0 days,
04:02:35
Downstream:
9.494 Mbps
Upstream:
1.129
Mbps
ADSL Settings
VPI/VCI:
0/38
Type:
PPPoA
Modulation:
G.992.5 Annex
A
Latency type:
Fast
Noise margin
(Down/Up):
10.4 dB / 5.9
dB
Line attenuation
(Down/Up):
29.3 dB / 13.3
dB
Output power
(Down/Up):
18.1 dBm / 12.0
dBm
FEC Events
(Down/Up):
0 / 0
CRC Events
(Down/Up):
207 / 76
Loss of Framing
(Local/Remote):
0 / 0
Loss of Signal
(Local/Remote):
0 / 0
Loss of Power
(Local/Remote):
0 / 0
HEC Events
(Down/Up):
727 / 45
Error Seconds
(Local/Remote):
233 / 89
FAQ
<script type="text/javascript">// paintProgressAndMessageOnBar(100,"The test has successfully completed" ); // </script>
Test1 comprises of two tests
1. Best Effort Test: -provides background information.
Download Speed
8135 Kbps
0 Kbps
21000 Kbps
Max Achievable Speed
Download speedachieved
during the test was - 8135 Kbps
For your connection, the acceptable
range of speeds is 4000-21000
Kbps.
Additional Information:
Your DSL Connection Rate
:9721 Kbps(DOWN-STREAM), 1155 Kbps(UP-STREAM)
IP Profile for
your line is - 8576 Kbps
2. Upstream
Test: -provides background information.
Upload Speed
897 Kbps
0 Kbps
1155 Kbps
Max Achievable Speed
>Upload speed
achieved during the test was - 897 Kbps
Additional
Information:
Upstream Rate IP profile on your line is - 1155
Kbps
We were unable to identify any
performance problem with your service at this time.
It is possible that any
problem you are currently, or had previously experienced may have been caused by
traffic congestion on the Internet or by the server you were accessing
responding slowly.
If you continue to encounter a problem with a specific
server, please contact the administrator of that server in the first
instance.
Please visit FAQ
section if you are unable To understand the test results.
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Thanks for your replys, believe it or not my line as been more stable, meaning alot less disconnects,infact very rare since i last had the snr reset, it auto changed to fast when mods manually reset the snr a month ago, i think it sounds like a joint or something, def not my internal wiring, its all brand new as of today and theres no change in sync so, the prob lies else where, i tried to tell bt before that theres some kind of fault between the pole and the exchange last time my speed dropped when i was on adsl max, it dropped to 300k i think, i rang up for a mac code because they wouldnt acknoweldge the fact and gottalked into adsl2+, everything went well untill 3 weeksago(around that time) i was up to 16meg sync, i posted it on here, after opening my big mouth my speed started to drop so i had a manuall snr reset, that solved it for a while, then i had that bad weather and it all screwed up, like i said previous, about 10-20mins before the reset my sync dropped to 1meg and line attenuation shot up to 65db, after the reset i had 12.5meg, 24 hours later i was down to 9meg, person on the other end of the phone at bt said my minimum sync should be around 12meg

Questions and answers on DLM, sync speed and real ...

I was confused about some DML details and posted on a BE forum (https://avatar.bethere.co.uk/forum/viewtopic.php?t=43542) and got what was to me an incredibly helpful response from Tom (drsox). I thought it would be of interest to some readers here so copy it below. Once again, many thanks Tom.
1) FTTC DLM applies only between the cabinet and the modem?
>> Yes, as there isn't any broadband / data signal going anywhere further down the line to the exchange if you are on FTTC!
2) What are the different parameters that apply on this hop? I know there is a current sync speed, a current snr, a target snr and an ip profile. Anything else?
>> The IP profile isn't really related to DLM, it just "follows" your sync rate. In the past the IP profile would take up to 3 days to "follow upwards", leaving you with a high sync and awful speeds! This has been changed now on 21cn and "RE-ppp"ing (rebooting the router) would force the IP Profile to update instantly.
DLM changes the SNR target. So where BE have hard coded / set SNR targets such as 3db, 6db, 9db, 12db etc.. They only change upon user request. BT use their DLM system where line instability or line error counts are collected and analysed, the SNR target and interleaving settings are then modified in increments to try and stabilise the line.
This image shows quite well how, over a 6 day period, BTs DLM noticed that my line fault was fixed. I didn't get the full speed back for a week.
3) Is the ip profile the same as the BRAS profile?
>>Yes
4) The DLM keeps statistics of errors etc to dynamically change the ip profile?
>> Changes the SNR target and interleaving for the line which will reduce the speed, and therefor the IP profile.
5) There is a general theory that the DLM is incapable of telling the difference between an error and a modem power cycle, so that power cycling can cause your profile to lower. Is that correct?
>> Yes, if you resync / power cycle your router multiple times in a day it is likely to try and "combat the line errors" and reduce your sync rate by increasing the SNR and / or interleaving on the line.
6) Can other connections and disconnections have the same effect? For example, if I reboot the router (where this is separate from the modem)? Or use the router interface to disconnect/reconnect the broadband?
>> PPP drops (router reboots while leaving the BT Openreach VDSL modem on and connected) won't affect DLM. The IP profile will match your sync rate upon reconnection of the PPP session.
7) If you have a low ip profile, does this mean that the sync is limited to the ip profile?
>> Other way around, if you have a low sync rate then the IP profile will match the sync rate. If you get an awful sync rate and the IP profile follows downwards, then you resync higher but the router "keeps the PPP session open" (which is possible if you resync quick enough) then your IP profile will stay low, even though the sync is high. Until you reboot your router or disconnect and reconnect the PPP session.
8) Can the sync rate change dynamically without a reconnection? If the ip profile gradually rises, will the cabinet force a resync to make sure the customer is actually getting the benefit of the higher ip profile, or must the user intervene with a modem resync?
>> See above - Sync can rise without affecting the IP Profile and the cabinet does not force a RE-PPP.
8) As I understand it, if the ip profile gets stupidly low for some reason, it can only be reset by BT wholesale? This will only be done after a visit to your home and a telephone call from the engineer to the BT wholesale central admin?
>> Mixed reports plus I don't think people understand the difference between sync speeds, line faults, the delay in DLM increasing sync after a fault.. I expect half the reports on the BT forum are not related to a stuck BRAS / IP profile. It is possible for the ISP or a BT engineer to reset the IP profile and possibly DLM training.
9) (8) This applies to all ISPs using BT Wholesale: some may be more willing to force this process to happen on behalf of their customers, but none can cirumvent it?
>> GEA providers (I believe) still have DLM but don't have BRAS / IP profiles unless they implement their own.
10) Who sets the snr? As I understand it, the customer has no direct control. Is this different for different ISPs?
>> Mixed information again, I believe that BT Wholesale give providers DLM override controls and SNR settings but none? (or few) ISPs use this system.
11) Real download/upload speeds are physically limited by the sync rate. They are also naturally limited by local limitations (such as wireless connections), server limitations, and congestion at various points along the route? Any more? The congestion along the route will vary bewteen ISPs as they use different routes with different capabilitues.
>> It is possible for BTs regional or local cabinet network to become congested. Supposedly the minimum speed you should achieve over the BT part of the network is 15mbps. ISPs such as Plusnet, BT etc.. then layer their own "discriminatory" traffic management on top of that (ie, slow down torrents etc.).
12) Real speeds are 'unnaturally' limited by throttling. This will also vary from ISP to ISP. Sky claims to have none, and BT none except for p2p. PlusNet and John Lewis have significant (but well explained)throttling. All the more expensive operators have none.
>> What you said
13) The ip profile affects the sync rate, and therefore actual speeds. Does the ip profile effect actual speeds in any other way?
>> Not quite right. The IP profile directly affects the speeds you can achieve but the sync rate affects the IP profile. The sync rate is determined by the stability and quality of your line and what DLM thinks it can cope with.
14) Many people (including AndrueC above) report real speeds from speedtests that are consistent and not close to the ip profile. These can't be explained by congestion (that would make them inconsistent). They can't be explained by server limitations, as they are consistent accross servers and the same servers give better speeds to other people. They can't be explained by local limitations, too many people claim sudden drops where the local conditions have not changed. They should not be able to be explained by throttling, as they as seen for many ISPs who do not throttle (I don't hold with the ISP lying theory here). What other factors are there that can explain these cases?
>> AndrueC and some other Sky customers have strange symptoms where speeds are around 20mbps rather than the full sync speed. The only logical explanation is either local cabinet congestion, contention between BT and the provider's network (not enough investment by the provider) or artificial traffic management on the providers side. It is also possible that the router that the customer has attached to their line is unsuitable for the higher speeds. For example an old ethernet router may only be able to cope with 20 or 30mbps! A friend of mine has a TP-Link ethernet router running Tomato on a BT 80mbps service but the TP-Link's CPU limitation causes his service to only perform at around 68mbps; he has a replacement router on order. (Obviously wifi will significantly reduce performance).
15) If you get a stupidly low ip profile, how long can you except it to take before it climbs to something more reasonable? (eg in my particular case, my profile is currently around 15Mb, and from BT service line tests should be around 58Mb). And the classic question, is it best to power cycle the modem (1) never, (2) occasionally (how often) or (3) never if at all possible? Mine did jump from 3.5Mb to 15Mb on one power cycle. Was that just coincidence?
>> My FTTC line took about 6 to 7 days to go from 40mbps to 80mbps after a line fault. It is possible that your 3.5mbps to 15mbps increase was the "re-ppp" affecting the BRAS profile and that your sync had slowly been increasing over time.

what a waste of money sending an engineer to "fix a fault" which does not exist. Precisely.
In my original BE post to which Tom so helpfully responded, I began: It seems to me that DLM is an excellent concept with a highly flawed implementation, both technically and administratively. I think that sending out an engineer to fix an obviously flawed profile is the main example of an adminastrative flaw. I understand (I can't remember source, maybe Tom again) that they are sometimes relaxing the requirement for a visit before reset.
Maybe the DLM system is too keen on stability vs speed. This will keep complaints down from many people: most users won't notice speed too much as long as it is reasonable, but will be upset if their Skype calls and browsing are being interrupted too often.
However, it does lead to complaints from people who notice the drops after an incidence (as in your thread that has drawn lots of interest), or who only get 50 instead of 60. The main technical flaw is that DLM can so easily be confused by drops from loss of power, too much modem recycling, etc, and then takes so long to recover.

How to look at Sync Speeds

Previously on the home hub 2 and BT Total broadband you could look at your up and down sync speeds under the hub manager. Obviously now the connection comes through the openreach modem and then into the home hub. How can i access the modem page to view the sync speed ?
IT SUPPORT TECHNICIAN - Comptia A+ Certified, MTA Qualified and MTSC qualified
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You can't. It's Openreach kit and the firmware is locked.
The only way to get a rough idea of your sync is from your IP profile which can be found by running a test at www.speedtester.bt.com.
The IP profile is about 96.7% of your sync rate.
If you want to say thanks for a helpful answer,please click on the Ratings star on the left-hand side If the the reply answers your question then please mark as ’Mark as Accepted Solution’

Sudden Strange Decrease in Sync Speed

On the afternoon of Thursday 4/3/2010 I had a strange change in my sync speed.
For about the past year I have enjoyed a solid 3.1 meg sync and same IP Profile. Sometimes its goes up to 3.5, but never below 3 meg. I know my neighbours get around 2 meg, but working in IT I invested the time in getting decent kit and improving the connection, despite the line length being approx 4km.
However, on thursday afternoon I noticed the PPP link was down, but the sync was still at 3.1 meg.
So I rebooted the router (D-Link DSL-2740B)and it came back as 1.6 meg sync and 1 meg IP Profile! (Attenuation and SNR stayed the same at 63.5 and 6.5 respectively)
Obviously I did the usual checks and unplugged everything, with the modem directly in the master socket, changed the cables, changed the filters, tried a second modem, checked line for audible noise, etc and over 24 hours got the sync back up to 1.8 meg with a 1.5 meg IP Profile, but I cannot seem to get it any faster!
Now I know a direct neighbour (downstream) has had lots of problems with his line recently and keeping synced, but it seems odd that suddenly my connection quality has dropped by 50%.
Could someone have done something at the Exchange (Braintree) that could have affected me so badly?
Any help appreciated.
Adam

see if leaving everything alone improves the problem, its possible that someone was in the exchange and caused the problem, more likley is that someone was using a none compliantdevice in the area and caused the problem, have any of the locals recently received/used something like a shiney remote control vehicle or helicopter?
if the problem persists then request help via the forum mods, or ring india for it

Big drop in sync speed

Hi
I wonder if some one can help, about 10 days ago i had a big drop in downstream sync speed from 5000-6000 to 288
BT have tested the line twice, and the second engineer has rebalanced the line, but i'm still stuck at the same sync speed
my IP profile from the speed tester was 250
my line stats are as follows
Line Mode
G.dmt
Line State
Show Time
Latency Type
Fast
Line Up Time
00:00:00:57
Line Coding
Trellis On
Line Up Count
1
Statistics
Downstream
Upstream
Line Rate
288
1056
Noise Margin
30.5 dB
8.0 dB
Line Attenuation
32.0 dB
21.0 dB
Output Power
12.2 dBm
11.3 dBm
any help would be appreciated
thanks

Well after 3 days, still no change
Download speedachieved during the test was - 156 Kbps
For your connection, the acceptable range of speedsis 50-250 Kbps.
Additional Information:
Your DSL Connection Rate :288 Kbps(DOWN-STREAM), 1056 Kbps(UP-STREAM)
IP Profile for your line is - 250 Kbps
The throughput of Best Efforts (BE) classes achieved during the test is - 10.26:26.92:62.82 (SBE:NBEBE)
These figures represent the ratio while sententiously passing Sub BE, Normal BE and Priority BE marked traffic.
The results of this test will vary depending on the way your ISP has decided to use these traffic classes.
Line Mode
G.dmt
Line State
Show Time
Latency Type
Fast
Line Up Time
03:02:25:53
Line Coding
Trellis On
Line Up Count
1
Statistics
Downstream
Upstream
Line Rate
288
1056
Noise Margin
30.5 dB
8.0 dB
Line Attenuation
32.0 dB
21.0 dB
Output Power
12.3 dBm
11.3 dBm
So do i reboot the router to see if the connection speed improves, or is their another problem ?
As additional information i have only 1 phone socket (the master) and no extensions, nothing has been changed in the set-up and all has been fine for years.
thanks

Drop in Sync Speed

Over the past few weeks I've seen a drop off in the Sync speed of my broadband and the Noise margin increase from 6dB to 8.5 dB.
I was connecting at 6Mbps but now it has dropped to 4.5Mbps - is there anything that I can do to get it back to what it was?
Everything has been fine with the connection itself - it has been rock solid in that it hasn't been disconnecting.
Line state:
Connected
Connection time:
0 days, 00:02:28
Downstream:
4.594 Mbps
Upstream:
448 Kbps
ADSL Settings
VPI/VCI:
0/38
Type:
PPPoA
Modulation:
G.992.1 Annex A
Latency type:
Interleaved
Noise margin (Down/Up):
8.5 dB / 22.0 dB
Line attenuation (Down/Up):
45.8 dB / 23.5 dB
Output power (Down/Up):
19.8 dBm / 12.6 dBm
FEC Events (Down/Up):
0 / 0
CRC Events (Down/Up):
0 / 0
Loss of Framing (Local/Remote):
0 / 0
Loss of Signal (Local/Remote):
0 / 0
Loss of Power (Local/Remote):
0 / 0
HEC Events (Down/Up):
0 / 0
Error Seconds (Local/Remote):
0 / 1

Looks like your target margin has moved from 6db to 9db, this is the values that equates to the initial noise margin needed for a stable sync.
You need to contact the mods on this site (click on one of their profiles for the link to them) and ask to have the targer margin reduced.
They may want to see a period of stable connection first but it is worth contacting them now since it takes them 3 days to reply normally.
A 9db target margin should give more line stability so unless you know what the problem was that caused it to increase (normally a series of resyncs, the default being 10 in 60 minutes) then you may want to check for a line problem first since otherwise if it is set to 6 it may go back to 9 again because of an underlying issue.
If my post was helpful then please click on the Ratings star on the left-hand side If the the reply answers your question fully then please select ’Mark as Accepted Solution’

Slow Sync Speed

Hi there,
I've read many posts on this forum and believe that my sync speed is quite low. I did a theoretical max speed test for my line attenuation at Kitz.co.uk and it said that I should have a speed in excess of 19000kbps with an ip profile of 16000kbps. I have been using a dodgy micro filter that disconnected the broadband everytime I recieved a phone call however I have purchased a new one and my router is running flawlessly with no dropouts. The noise margin is constantly at 6db. I believe that this may have flagged my line to be faulty and thus resolved a slower sync speed to compensate.
I disconnected the broadband roughly 8 days ago after it had been connected for about 15 days expecting to sync at a higher speed but infact the sync speed dropped by several hundres kbps.
Is there any way that I can sync at a higher speed?
Thanks in advance

Ok I ran cat /proc/avalanche/avsar_modem_stats via telnet
AR7 DSL Modem Statistics:
[DSL Modem Stats]
US Connection Rate: 828 DS Connection Rate: 10544
DS Line Attenuation: 23 DS Margin: 5
US Line Attenuation: 13 US Margin: 9
US Payload : 3985202784 DS Payload: 3901859552
US Superframe Cnt : 42408111 DS Superframe Cnt: 42408111
US Transmit Power : 0 DS Transmit Power: 0
LOS errors: 0 SEF errors: 0
Errored Seconds: 3592 Severely Err Secs: 4
Frame mode: 0 Max Frame mode: 0
Trained Path: 1 US Peak Cell Rate: 1952
Trained Mode: 16 Selected Mode: 1
ATUC Vendor Code: 54535443 ATUC Revision: 3
Hybrid Selected: 1 Trellis: 1
Showtime Count: 1 DS Max Attainable Bit Rate: 11328 kbps
BitSwap: 1 US Max Attainable Bit Rate: 1284966 bps
Annex: AnxA psd_mask_qualifier: 0x0000
Power Management Status: L0 DS HLINSC: 0
US ACTPSD: -345 DS ACTPSD: -366
Total init. errors: 0 Total init. timeouts: 0
Showtime init. errors: 0 Showtime init. timeouts: 0
Last showtime init. errors: 0 Last showtime init. timeouts: 0
ATUC ghsVid: b5 00 54 53 54 43 05 10
T1413Vid: 00 00 T1413Rev: 00 VendorRev: 00
ATUR ghsVid: b5 00 54 53 54 43 00 00
T1413Vid: 00 00 T1413Rev: 00 VendorRev: 00
[Upstream (TX) Interleave path]
CRC: 351 FEC: 275203 NCD: 0
LCD: 0 HEC: 220
[Downstream (RX) Interleave path]
CRC: 5290 FEC: 67573629 NCD: 0
LCD: 0 HEC: 0
[Upstream (TX) Fast path]
CRC: 0 FEC: 0 NCD: 0
LCD: 0 HEC: 0
[Downstream (RX) Fast path]
CRC: 0 FEC: 0 NCD: 0
LCD: 0 HEC: 0
[ATM Stats]
[Upstream/TX]
Good Cell Cnt: 83025058
Idle Cell Cnt: 1324844211
Tx Packets Dropped Count: 0
Tx Bad Packets Count: 27
[Downstream/RX)]
Good Cell Cnt: 1244509050
Idle Cell Cnt: 3798720619
Bad Hec Cell Cnt: 84325
Overflow Dropped Cell Cnt: 0
Rx Packets Dropped Count: 0
Rx Bad Packets Count: 0
[SAR AAL5 Stats]
Tx PDU's: 27918363
Rx PDU's: 43978168
Tx Total Bytes: 2729375221
Rx Total Bytes: 2652108237
Tx Total Error Counts: 0
Rx Total Error Counts: 1569
[OAM Stats]
Near End F5 Loop Back Count: 0
Near End F4 Loop Back Count: 0
Far End F5 Loop Back Count: 0
Far End F4 Loop Back Count: 0
SAR OAM Ping Response Drop Count=0
I'm guessing that I am on ADSL as it says annex A? Does that mean that I can access any higher speeds as I'm not on ADSL2/+? or would forcing the modulation on the router help?
Update: It is set to trained mode 16 which is ADSL2+ What is going on here, I just restarted the router and it is now slower.
Thanks

Loss of sync speed (over 50%), openreach say line ...

Hi,
I hope someone can help!
For the last 24 months my sync speed has been a consistent and stable 7000+ so my BRAS profile was 6500.
Last weekend the connection dropped and now will not sync any faster than ~3000, so half the usual speed, well actually less because my BRAS is now 2500
I have checked all ADSL filters, connected the ADSL router directly to the master socket removing face place to disconnect the extension wiring, tried a different and known working router - another home hub and a Cisco, etc etc smae results.
The SNR on the line is unchanged at 35dB as previously be good for 7000+, so I can't understand why my sync is now 3000
At a sync of 3000 the SNR is 6dB (previously 7000 sync @ 6dB) which would suggest the line
is noiser than before, although no additional noise is heard on the voice line.
Openreach have been to visit - the line passed all of their tests. The openreach engineer also could not sync faster than ~3000.
He went to the exchange and redid the wiring to the DLSAM - no speed improvement.
He called me from the exchange and said that the DLSAM is "sending to me @ 7.2" - so I thought great, he's sorted it, then he told me no it would not be any better as "the line loses 1 meg for each km" .... so we entered a bit of dialogue about how the line could not be synced @7.x at the exchange end and 3.x at my end, about line sync, DMT tones etc etc I think I was going over his head! He then went on about maybe it's slower because there are now more users on the exchange - again I explained about how the contention actually works on the VC to the BT core, not by BT Wholesale decreasing sync speed on the DSLAM sync... again going over his head....
So basically he thinks it's fine as the line tested ok and I doubt I'll get any further change.
Now here is the strange thing -
...it was only after the call that I realised that he'd have no visibility of the sync speed on the DSLAM so when he said it's "sending to me at 7.2" he meant that he was plugged directly into the DSLAM port with his portable tester... Now he should be syncing @ 8Meg when connected directly to the DSLAM in the exchange, so it must be a fault on the DSLAM port / profile?
How do I go about getting BT wholesale to move me to a different port? Not only has my speed decreased but I get random re-syncs.
Please help!!! :-)
Cheers
Matt
PS provider is BT Total Broadband

Here's the other strange thing - I just reset the line to clear the stats, and made sure no other PCs were connected, i.e no significant volume of data being send/received, and in 5 minutes I have 160,000 FEC/Interleave errors - that's not right surely?
ADSL line status
Connection information
Line state
Connected
Connection time
0 days, 0:05:17
Downstream
3,392 Kbps
Upstream
448 Kbps
ADSL settings
VPI/VCI
0/38
Type
PPPoA
Modulation
ITU-T G.992.1
Latency type
Interleaved
Noise margin (Down/Up)
5.9 dB / 22.0 dB
Line attenuation (Down/Up)
36.0 dB / 21.0 dB
Output power (Down/Up)
19.5 dBm / 11.8 dBm
Loss of Framing (Local)
64
Loss of Signal (Local)
11
Loss of Power (Local)
0
FEC Errors (Down/Up)
165234 / 2
CRC Errors (Down/Up)
217 / 2147480000
HEC Errors (Down/Up)
nil / 0
Error Seconds (Local)
685

Downloads slower than sync speed

I got connected a few weeks ago an happy with the sync speeds. 73 Down 19.9 Up The problem is no matter what I download I can't go over 55Mbit I have done a few speedtests and can't get over 55Mbit. Is there something wrong with my router or the line? I'm have a DSL N68U.
Here are my stats

TimCurtis wrote:
The problem seems to be with your profile - from the BT speed test.
DLM has set your sync speeds , although perhaps a little lower than might be expected, at 73k. From that you'd expect the profile to be at about the same figure, but yours is a lot lower which is the problem I'd guess.
Exactly what I was thinking. I was under the impression that with the current set up and under normal conditions ADSL2+ should set the downstream IP Profile to 88.2% of downstream sync and VDSL2 should set it to 96.8% of downstream sync.
Take my example. My line is capable of VDSL2 speeds of over 80Mbps. I'm on Infinity 1 so my downstream sync is capped at 40Mbps and my modem does sync at that. My downstream IP Profile is 38.72Mbps (exactly 96.8% of sync).
Kas,
Your stats show that your line is capable of 102.66Mbps. You are on Infinty 2 so your downstream sync has been capped at 80Mbps and in fact is currently synced at 73.46Mbps (possibly due to some slight noise on the line?).
However your downstream IP Profile is 57.71Mbps which is only 78.6% of sync. When downloading data via the internet using IP you will not get a speed greater than this limit. That explains your test results.
So the question that someone more knowledgeable might be able to answer is why the IP profile is set so low compared to sync speed?

Increase in attainable rates and sync speed

I've noticed that my line is now syncing at 79999 down and 20000up, lasst week, and for the past 6 months the attainable rate has been 60000 down and 15000 up,
I'm still only getting 71000 down via the bt speedtest and 9000up, getting slightly better results on bbc though.
Also noticed my latency to the bbc is down from 25ms to 21ms
have there been any changes to the network or is this the DLM deciding that my line is good enough to handle higher speeds?

I don't think your line will improve even more, as you are at the limit of your package.
If you look at your modem stats you will see both sync rate and max attainable rate. The max attainable rate will only change significantly if something changes in your line. The sync rate will change as DLM thinks fit. If you see your max attainable rate is over around 90000, then maybe you could get more stable sync rate if BT offered a higher level Infinity package.
DLM will always keep your sync rate below the max attainable for stability. For reference, my values are a good but not perfect:
Max: Upstream rate = 23773 Kbps, Downstream rate = 81184 Kbps
Path: 0, Upstream rate = 20000 Kbps, Downstream rate = 73999 Kbps
Down Up SNR (dB): 7.9 14.5
Over the month or so I have been monitoring, my max attainable has dropped slightly, from just over 85000 to values around 82000. My sync speeds have gone up a lot to reach their current appropriate value, because I had had a previous wiring issue that had lowered my DLM.

Continual Drop in Sync Speed

I have been experiencing a continual drop on sync speed and thus actual line speed over the last few weeks. I had a HH4 replaced aftger teh last one died and since then the line speed seems to be getting slower and slower.
I am on DSLMax (good old ADSL) and normally sync around 8mb as am very close to the actual exchange - am now down to 6.4mb and am sure it will drop again.
Normal instructions from the phone support has been applied - reset hub etc.... and has not made a difference...
Can I ask one of the mod's to try and help out - see why the line is syncing lower than it normally does/has been for the last 3 years....
thanks
Pete

in order for the forum members to help please can you post the adsl stats from your router you may need to 'show detail' to get all stats (if hub enter 192.168.1.254 in your browser and navigate to adsl or if HH4/5 then go to troubleshooting then logs and you are looking for 2 line together when hub last connected to internet and they will show your connection speed and noise margin or if netgear enter 192.168.0.1). Then run btspeedtester (MAC users may have problems). when first test completes then run diagnostic test and post the results ( do not reset the router).
are you connected directly via a filter to the NTE5 master or test socket or to somewhere else? Is the master the only phone socket in your home?
Have you tried the quiet line test? - dial 17070 option 2 - should hear nothing - best done with a corded phone. if cordless phone you may hear a 'dull hum' which is normal
Someone may then be able to offer help/assistance/suggestions to your problem
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What is sync speed limited by?

Assuming my line is all ok, what is sync speed limited by?
The reason i ask is im told my exchange and line is rated for 2 meg (which i was syncing at around 2.5), on sppedtest was getting 2 meg download...so all is looking well...but then randomly one saturday (about 2 weeks ago) i changed over a filter and disconnected the extension wiring, reset the home hub and synced at 3.9 meg, with a nice SNR of 5.9db. Obviously i was well impressed as my speed went up!
Why was this sync different? As im yet to get anywhere near that again?

neild7744 wrote:
Assuming my line is all ok, what is sync speed limited by?
It's essentially governed by the characteristics of the line. Even if the line is OK, it'll still have properties that could limit the possible speed to an extent. eg lines all attenuate the signal, even good lines.
There are other factors, "hard" caps for example can be imposed by the hardware, possibly due to the service you're buying. An "up to 8Mbps" service will never go faster than that, even if the line is capable.
The reason i ask is im told my exchange and line is rated for 2 meg (which i was syncing at around 2.5), on sppedtest was getting 2 meg download...so all is looking well...
Not really relevant to your question, but...while your line may well be "rated for 2 meg" the exchange will be capable of more than that. If you get anything less, it's due to one of the reasons above.
but then randomly one saturday (about 2 weeks ago) i changed over a filter and disconnected the extension wiring, reset the home hub and synced at 3.9 meg, with a nice SNR of 5.9db. Obviously i was well impressed as my speed went up!
Why was this sync different? As im yet to get anywhere near that again?
On the face of it, it sounds as though either the filter or the extension wiring is causing some noise/interference on the line, which was slowing things down.
If this behaviour is consistent and repeatable, it should be fairly easy to find and eliminate the cause, which may give a very worthwhile improvement to your speed.

ITouch Sync Speed to Vista Laptop

If I just connect my Itouch to my laptop and add new tunes via Itunes then the sync speed is very slow. However, if I also connect my old Ipod 30Gb video at the same time to any other USB port the Itouch sync speed increases dramatically! Much faster - almost as quick as the old Ipod. Is this an Itunes issue? It's a bit weird as the old Ipod syncs correctly on it's own. The Itouch has the latest - 3.0 - firmware.
Regards Graham

This ABSOLUTELY solved my problem... everyone having hang up problems check this out! It worked perfect. Thanks for the help man... Hope itunes have this fixed soon.

ATV sync speed super stupid slow.

How quickly does it take you to sync one 45 minute TV show from your ATV to your computer? Mine takes me about 45 minutes. Is this normal? If not, how can i speed this up? I have a wireless Linksys router that hasn't been slow transferring files from my MBP to my G5, or any other capacity. If it is the ATV, why does the sync speed blow?

Well, it's new in that it's always been this way since i bought it new. It's just always seemed slow. It took about 2 hours to sync 8 shows from X-Files Season 2 last night. That works out to being about 2.5 GB, but that STILL seems super slow for this network. I have no issues streaming, so i wonder if this length is supposed to happen.
Now, just to be clear, i have a wireless Linksys router (WRT54G V8). I'm pretty savvy re: computers, but i'm a bit weak on networks, so it might not be optimized. I know sometimes my handheld phone can interfere with me streaming to my airport, but only when it is in use.
Otherwise, the router is hardwired to a Comcast modem. Thoughts?

Sync speed / IP profile

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