RE: Broadband ADSL Help

["Marcus Warrington" <marcus.warrington@xxxxxxxxxx>]

I assume when you say "download speeds" you actually mean
the line synch
speed.



My understanding of all this smoke and mirrors is that you router will
try and synch the line to obtain a Signal To Noise Ratio (SNR) of 6.5db
i.e. it can hear 6.5db of signal above the background noise etc. As the
line synch speed increases the SNR will decrease and as the line synch
speed decreases the SNR will increase.  Therefore the speed you get
depends on how good your line is (i.e. how much SNR you have). This is
all subject to the maximum speed of your ADSL connection, that may also
be limited by the exchange DSLAM.



BT also add more confusion to the mix by limiting the maximum connection
speed based on how reliably you have connected in the past.. they have
some acronym for it ..BRAS (?) ..may be worth asking your ISP to have
this reset.



The fact that the two routers are showing different results is either
because the Netgear has a much better chipset and can see more SNR than
the other one or the line SNR is varying widely and when you reconnected
it was much better so got a better connection.



I'm on Be Unlimited using a Netgear834GT and see that my SNR drops from
6.5db during daylight hours to about 3 - 2.5db at night.. I think this
is quite common for SNR to drop at night and may be to do with more
electrical activity (street lights etc) near the telephone line? I
always synch at a better speed if I reconnect during the day (higher SNR
available) than if I resynch at night (lower SNR available).





Marcus

________________________________

From: ukha_d@xxxxxxx [mailto:ukha_d@xxxxxxx] On Behalf
Of Mark Golledge
Sent: 04 February 2008 21:54
To: ukha_d@xxxxxxx
Subject: Re: [ukha_d] Broadband ADSL Help



Ok,

I've done some checks. According to speedtest, I'm getting download
speeds
of 1946kb/s and upload speeds of 367kb/s. I know that I've previously
been
achieving download speeds of 3000kb/s so something is not right there.

Both those speeds are what is being achieved on the laptop (and desktop
PC).

However, just gone into Netgear settings and downstream connection speed
is
showing 3488kb/s and upstream 448kb/s.

Any ideas?

Line attenuation is showing 53db downstream and 15.5db upstream and snr
is
showing 3bd downstream and 19db upstream. Line attentuation seems kind
of
high and snr low (should be the other way around I think).

Mark

On Feb 4, 2008 9:40 PM, Andy Davies <dajdavies@xxxxxxx
<mailto:dajdavies%40gmail.com>
> wrote:

> We had problems with our 3Com router and Vodafone, worked fine when we
> first moved in and then it would start to be unable to keep an IP
> address, changed to a Netgear router and everything was fine.
>
> I seem to remember seeing something in the Register that there's a
> 'known issue' with some routers and the BT DSLAMs which only comes to
> light when the DSLAMs are updated.
>
> Andy
>
>
> On Feb 4, 2008 7:40 PM, Mark Golledge <markgolledge@xxxxxxx
<mailto:markgolledge%40googlemail.com>
<markgolledge%40googlemail.com>>
> wrote:
> > Hi everyone,
> >
> > I've been having some problems with my broadband recently. About
6
> months
> > ago we moved across to Vodafone at Home from BT for broadband and
home
> > phone.
> >
> > Al has been fine except over the last few months I've come across
more
> and
> > more times where my internet connection seems to be dropping
> occasionally.
> >
> > Happened for quite a bit on Saturday to such an extent that I
couldn't
> get
> > on the internet at all.
> >
> > Am using a Router (Netgear DG834G) connected via microfilter to
the
> phone
> > line.
> >
> > No problems with wireless at all, that stays fine. It is the ADSL
light
> on
> > the router which keeps dropping and then re-connecting.
> >
> > Have checked with Vodafone and they said it was the wireless but
advised
> > them it can't be because the wireles is still connected. No
recognisable
> > problem with phone line.
> >
> > Any ideas?
> >
> > --
> >
> > Mark Golledge
> > E: mark@xxxxxxx <mailto:mark%40markgolledge.com>
<mark%40markgolledge.com>
> > W: www.markgolledge.com
> >
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
> > **** Sponsored By http://www.Berble.com <http://www.Berble.com>
****
> > **** Computers You Carry ****
> >
> >
> >
> >
> >
> >
> >
>
>

--

Mark Golledge
E: mark@xxxxxxx <mailto:mark%40markgolledge.com>
W: www.markgolledge.com

[Non-text portions of this message have been removed]





[Non-text portions of this message have been removed]