What is this "loss of sync", and do I have it?

My bb connection over the past couple of days has been very 'flakey'.
Not a technical term, I know, but the symptoms are; retrieving news
messages in fits and starts with long pauses (upto 10-20 seconds)
between newsgroup messages, or in the middle of messages with
attachments; likewise stopping & starting in the middle of downloads.

My setup is ISP-UKOnline 2MB on a LLU exchange with a Netgear
modem/wireless router. The router's statistics are: Line attenuation
(downstream)-53dB, Noise margin varying between 2dB to 6dB.
Previously the line attenuation was at 54dB until a couple of days
ago, and the noise margin has varied between 8dB to 1dB with no loss
of connection. The upstream line attenuation has remained the same at
15.5dB, but the noise margin has dropped from 20dB to 18dB.

I've tried it with a Speedtouch USB modem and it's not much better
(but slightly better). I don't know how to get any figures out of it,
so I don't have any quantative information.

Any ideas?
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have you strayed?"

Hugo Nebula wrote:
> My bb connection over the past couple of days has been very
> 'flakey'. Not a technical term, I know, but the symptoms are;
> retrieving news messages in fits and starts with long pauses (upto
> 10-20 seconds) between newsgroup messages, or in the middle of
> messages with attachments; likewise stopping & starting in the
> middle of downloads.
>
> My setup is ISP-UKOnline 2MB on a LLU exchange with a Netgear
> modem/wireless router. The router's statistics are: Line
> attenuation (downstream)-53dB, Noise margin varying between 2dB to
> 6dB. Previously the line attenuation was at 54dB until a couple of
> days ago, and the noise margin has varied between 8dB to 1dB with
> no loss of connection. The upstream line attenuation has remained
> the same at
> 15.5dB, but the noise margin has dropped from 20dB to 18dB.
>
> I've tried it with a Speedtouch USB modem and it's not much better
> (but slightly better). I don't know how to get any figures out of
> it, so I don't have any quantative information.
>
> Any ideas?

You have been provided a service which your line cannot support, your
loop attenuation is at least 10dB over the top & your SNR is below
what a substainable link will support, the limit for 2Mb is 43dB Loop
& around 10dB SNR...

The Netgear router isn't one of the most stable routers to use as
well...

If you do get your ISP to investigate & if they get a OpenReach
engineer to site don't be suprised if they lower the speed of your
connection to 1Mb...

In an earlier contribution to this discussion,
Hugo Nebula <abuse@localhost> wrote:

> My bb connection over the past couple of days has been very 'flakey'.
> Not a technical term, I know, but the symptoms are; retrieving news
> messages in fits and starts with long pauses (upto 10-20 seconds)
> between newsgroup messages, or in the middle of messages with
> attachments; likewise stopping & starting in the middle of downloads.
>
> My setup is ISP-UKOnline 2MB on a LLU exchange with a Netgear
> modem/wireless router. The router's statistics are: Line attenuation
> (downstream)-53dB, Noise margin varying between 2dB to 6dB.
> Previously the line attenuation was at 54dB until a couple of days
> ago, and the noise margin has varied between 8dB to 1dB with no loss
> of connection. The upstream line attenuation has remained the same at
> 15.5dB, but the noise margin has dropped from 20dB to 18dB.
>
> I've tried it with a Speedtouch USB modem and it's not much better
> (but slightly better). I don't know how to get any figures out of it,
> so I don't have any quantative information.
>
> Any ideas?

Does your router have synch and on-line status lights? Do they go out when
the problem occurs? Does the log file show disconnections and multiple
re-connection attempts?

As kraftee says, it looks like your line can't sustain a reliable 2M
service.
--
Cheers,
Tim
______
Please reply to newsgroup. Reply address is invalid.

"Hugo Nebula" <abuse@localhost> wrote in message
news:(E-Mail Removed)...
> My bb connection over the past couple of days has been very 'flakey'.
> Not a technical term, I know, but the symptoms are; retrieving news
> messages in fits and starts with long pauses (upto 10-20 seconds)
> between newsgroup messages, or in the middle of messages with
> attachments; likewise stopping & starting in the middle of downloads.
>
> My setup is ISP-UKOnline 2MB on a LLU exchange with a Netgear
> modem/wireless router. The router's statistics are: Line attenuation
> (downstream)-53dB, Noise margin varying between 2dB to 6dB.
> Previously the line attenuation was at 54dB until a couple of days
> ago, and the noise margin has varied between 8dB to 1dB with no loss
> of connection. The upstream line attenuation has remained the same at
> 15.5dB, but the noise margin has dropped from 20dB to 18dB.
>
> I've tried it with a Speedtouch USB modem and it's not much better
> (but slightly better). I don't know how to get any figures out of it,
> so I don't have any quantative information.
>
> Any ideas?
> --
> Hugo Nebula
> "If no-one on the internet wants a piece of this,
> just how far from the pack have you strayed?"

Are those stats from being pluged directly into the BT main socket? if not
try that.

What router firmware do you have installed? maybe a newer version would
help, it has helped some.

"Hugo Nebula" <abuse@localhost> wrote in message
news:(E-Mail Removed)...
> My bb connection over the past couple of days has been very 'flakey'.
> Not a technical term, I know, but the symptoms are; retrieving news
> messages in fits and starts with long pauses (upto 10-20 seconds)
> between newsgroup messages, or in the middle of messages with
> attachments; likewise stopping & starting in the middle of downloads.
>
> My setup is ISP-UKOnline 2MB on a LLU exchange with a Netgear
> modem/wireless router. The router's statistics are: Line attenuation
> (downstream)-53dB, Noise margin varying between 2dB to 6dB.
> Previously the line attenuation was at 54dB until a couple of days
> ago, and the noise margin has varied between 8dB to 1dB with no loss
> of connection. The upstream line attenuation has remained the same at
> 15.5dB, but the noise margin has dropped from 20dB to 18dB.
>
> I've tried it with a Speedtouch USB modem and it's not much better
> (but slightly better). I don't know how to get any figures out of it,
> so I don't have any quantative information.
>
> Any ideas?
I have a similar problem as you, although I don't suffer loss of
connections, my download speed suffer as the day progresses. By 3pm my
download speed gets as low as 700kbps, mornings they are 1926kbps.
Next day it repeats, seems my line degrades as the day goes by, bit like
me!! then perks up again by 8pm, not like me!!
My noise margin is varying between 8dB to 26dB.
My IPS is now looking into it for me, ( Nildram ) but I might have to go
back to 1Mg to get a stable connection.
ADSL Modem is a ZyXEL 660HW. Also used my Netgear DG834Gv2, both have the
latest firmware, I get the same problem with both routers.
I don't trust BT, they told me I could get a 2Mg line, but BT did not tell
it might be unsustainable!!

> --
> Hugo Nebula
> "If no-one on the internet wants a piece of this,
> just how far from the pack have you strayed?"

On Sun, 8 Jan 2006 14:28:40 -0000, a particular chimpanzee named
"Tiscali Tim" <(E-Mail Removed)> randomly hit the keyboard and
produced:

>Does your router have synch and on-line status lights? Do they go out when
>the problem occurs? Does the log file show disconnections and multiple
>re-connection attempts?

The router is rock-solid (and, trust me, I know all about dodgy
routers resetting themselves). The line has been OK for the past
month or so at 54dB. Surely, the lower the better?
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have you strayed?"

In an earlier contribution to this discussion,
Hugo Nebula <abuse@localhost> wrote:

> On Sun, 8 Jan 2006 14:28:40 -0000, a particular chimpanzee named
> "Tiscali Tim" <(E-Mail Removed)> randomly hit the keyboard and
> produced:
>
>> Does your router have synch and on-line status lights? Do they go
>> out when the problem occurs? Does the log file show disconnections
>> and multiple re-connection attempts?
>
> The router is rock-solid (and, trust me, I know all about dodgy
> routers resetting themselves). The line has been OK for the past
> month or so at 54dB. Surely, the lower the better?

So you haven't got loss of synch, then - to answer your initial question.
[If you had, the status lights on the router would go out, or flash].

Does your router have a status page which reports how many CRC and/or HEC
errors there have been? If the error rate goes sky high due to insufficient
noise margin, the effective throughput rate can plummet even without losing
synch - because each frame has to be sent multiple times before arriving
successfully.

Attenuation needs to be as low as possible, and noise margin as high as
possible. Looking at my router's status as I type this, I have a downstream
attenuation of 54dB and a downstream noise margin of 19.5dB - on a 1M line,
deemed by BT not to be worthy of anything faster.
--
Cheers,
Tim
______
Please reply to newsgroup. Reply address is invalid.

On Sun, 8 Jan 2006 18:43:48 -0000, a particular chimpanzee named
"Tiscali Tim" <(E-Mail Removed)> randomly hit the keyboard and
produced:

>Does your router have a status page which reports how many CRC and/or HEC
>errors there have been? If the error rate goes sky high due to insufficient
>noise margin, the effective throughput rate can plummet even without losing
>synch - because each frame has to be sent multiple times before arriving
>successfully.

Not sure; is it in this lot?

Port Status TxPkts RxPkts Collisions Tx B/s Rx B/s Up Time
WAN PPPoA 11541 13274 0 54 607 06:37:18
LAN 10M/100M 37622 40639 0 64 50 44:30:12
WLAN 11M/54M 1506867 1739250 0 3124 1840 44:30:02

ADSL Link Downstream Upstream
Connection Speed 2048 kbps 256 kbps
Line Attenuation 53 db 15.5 db
Noise Margin 1 db 18 db

Noise margin has been this low before (although it's now jumped to
2147483645 db which may not be entirely accurate).

>Attenuation needs to be as low as possible, and noise margin as high as
>possible. Looking at my router's status as I type this, I have a downstream
>attenuation of 54dB and a downstream noise margin of 19.5dB - on a 1M line,
>deemed by BT not to be worthy of anything faster.

It's a LLU line; BT say it'll only get 512kbps, my ISP claim I could
upgrade to 4Mb if I wanted.
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have you strayed?"

On Sun, 8 Jan 2006 15:23:31 -0000, a particular chimpanzee named "It's
Me" <(E-Mail Removed)> randomly hit the keyboard and produced:

>Are those stats from being pluged directly into the BT main socket? if not
>try that.

Done; noise margin has increased slightly to between 6-10 db, but all
other figures are the same.
>
>What router firmware do you have installed? maybe a newer version would
>help, it has helped some.

I have the latest version.
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have you strayed?"

On Sun, 08 Jan 2006 19:57:26 +0000, a particular chimpanzee named Hugo
Nebula <abuse@localhost> randomly hit the keyboard and produced:

>On Sun, 8 Jan 2006 15:23:31 -0000, a particular chimpanzee named "It's
>Me" <(E-Mail Removed)> randomly hit the keyboard and produced:
>
>>Are those stats from being pluged directly into the BT main socket? if not
>>try that.
>
>Done; noise margin has increased slightly to between 6-10 db, but all
>other figures are the same.

And plugging it back into the extension socket via a filter raises it
to 7-11 db. As our American cousins say, "go figure!".
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have you strayed?"