- Info please re connection ratio of NTL
- Posted by ted_radioham on August 20th, 2005
Ias the NTL connection ration 15 or 20:1 on Cable 2m connection does anyone
know please ?.
- Posted by Tim Clark on August 20th, 2005
In article <DbFNe.11153$bf6.1035@newsfe1-gui.ntli.net>,
"ted_radioham" <deletenospam--123321@hotmail.com> writes:
NTL don't provide any information about any contention ratios which may
apply in their network. With ADSL the published contention ratio relates
to one specific control point. Cable will have a different network
topology, with different bottlenecks. Perhaps the most comparable figure
might be the number of customers sharing an ethernet-type segment of the
cable spectrum, divided by the multiple of 2 Mbps that the segment runs
at. There's not much chance of getting that info out of NTL though.
--
Tim Clark
- Posted by ted_radioham on August 21st, 2005
Ok thanks anyhow I have since po found out on their FAQ and it appears that
it is 20:1 so thanks anyhow.
Q. I've heard that contention ratios differ between cable and ADSL
broadband. Can you explain?
A. Yes. We have engineered our local access network to provide a 20:1
contention ratio in comparison to a number of ADSL providers who have
contention ratios as high as 50:1. The "contention ratio" is the number of
customers that share one unit of data capacity, meaning the lower the
contention ratio the higher the quality of the local access network.
- Posted by poster on August 21st, 2005
On 21 Aug 2005 18:15 GMT, "ted_radioham" wrote:
Good marketing ploy I think... "bad-mouth" the ADSL service, but with no
proof that a 20:1 contention is "much" better. I have used BT-supplied
ADSL at 50:1 from 4 different ISPs over the past 30 months (yes, I've had
both lines, with different ISPs, for various periods of time too) and all
were nominally at 50:1 yet I've not seen speed problems and traffic (just
checked - 611.76 MB, 6.52 GB, 2.35 GB <- traffic recorded by Plus.Net
for my connection for Fri, Sat, Sun) seems completely unaffected on my
cheap + cheerful 14.99 Broadband Plus account. Months ago, when PN was
about to implement a "traffic calming" measure (affecting those that used
to download 200-600 GB a month) there was a comment about the nominal 50:1
and it is known by BT and ISPs to be "unworkable" so they indicated that on
their connections it was unuusual to be worse than 30:1. Peter Morgan.
[ Yes, I am "biassed" against cable - there is no service here for miles! ]
--
UK ADSL <http://tinyurl.com/5jpa4> - Happy to save cash with Plus.Net!!
- Posted by Phil Thompson on August 21st, 2005
On Sun, 21 Aug 2005 19:27:45 +0100, poster <us-mail@rocketmail.com>
wrote:
BT have always said "up to 50:1" in any case. OFCOM found it to be
15:1 to 25:1 with some flawed thinking.
Phil
--
Tiscali - dialup speeds at Broadband prices, see
http://bbs.adslguide.org.uk/postlist...&Board=tiscali
AOL - the unlimited ISP of choice for heavy downloaders.
- Posted by stephen on August 23rd, 2005
"ted_radioham" <deletenospam--123321@hotmail.com> wrote in message
news:rx3Oe.17821$4y6.17631@newsfe7-gui.ntli.net...
the contention ratio is a worst case number - i suspect that since building
the backhaul plumbing probably starts with 155 Mbps or Gigabit Ethernet
(depending on what is there), a lot of services have much lower contention
ratios. the flip side is that when it degrades as the aggregate user load
goes up, you are still getting what you paid for......
the other effect is that as the number of users goes up, as long as the
average usage is low, the statistical gain should mean fewer contention
effects actually hit in practice.
1 other thing to watch is that the backhaul link has symmetric bandwidth and
the last mile link doesnt. Since last mile speed, number of users and the
backhaul bandwidth dictate contention, the published contention number in
ADSL is for the download direction - upload has a lower contention (but
lower available link speed for each user).
Cable is worse off here since the way that broadband is shared across a
cable segment means that uplink bandwidth is more resource intensive, and a
cable setup normally has lower speed uplinks than ADSL (at least on current
UK services).
this may sound irrelevant, but the slower speed direction limits you when
you need symmetric bandwidth - for a VoIP call for example. So cable users
may have to use a higher compression codec with voip than ADSL users who get
nominally equivalent link speeds.
--
Regards
Stephen Hope - return address needs fewer xxs
- Posted by Angus Robertson - Magenta Systems Ltd on August 24th, 2005
In article <CTMOe.616$ER4.478@newsfe3-gui.ntli.net>,
stephen_hope.xx@ntlxworld.com (stephen) wrote:
Cable did originally offer 128K uplink, but this was increased for 1M
download services to 256K, and the higher end offering on Telewest is
currently 384K which is not available on ADSL. Telewest is upgrading
all 512/128K services to 2M/256K later this year.
Angus
- Posted by Phil Thompson on August 24th, 2005
On Wed, 24 Aug 2005 00:27:39 GMT, angus@magsys.co.uk (Angus Robertson
- Magenta Systems Ltd) wrote:
Bulldog and UKOnline offer >400k upload speeds on ADSL.
Phil
--
Tiscali - dialup speeds at Broadband prices, see
http://bbs.adslguide.org.uk/postlist...&Board=tiscali
AOL - the unlimited ISP of choice for heavy downloaders.
