[SunRescue] speakeasy.net

[Dave Reader]

On Fri, 30 Mar 2001, David Cantrell wrote:

> I'm on 512/256 ADSL using BT as the carrier.  I get under 50ms to pretty
> nearly anywhere in .uk, around the same to the east coast of .us and
> 150ms to the west coast and south.  It's only about 300 to 350ms to .au!
> My ISP - nildram.net - are very clueful indeed.  They reply to emails
> promptly, and they even return phone calls when they say they will.  And
> they let me run whatever I want at home, no restrictions at all.

It's worth noting that there are many differences between the service
provision here and in the US.

BT's system is PPPoA, with ATM PVCs being established over BT's national
ATM network, through (eventually) to a BT managed router sited at the ISP
(known as the 'home gateway').

Technically it's a good system. In reality it's been rolled out with too
many political motivations and influences. (BT are supposed to be a telco,
but they are trying to compete with their customers... the ISPs).

Performance depends on two variables - cell transmission over BT's ATM
network, and then IP access at the ISP.

BT's planned contention for the ATM network is 20:1 for 'business' grade
services and 50:1 for 'residential' grade - the distinction is actually
Ethernet (ie, router) versus USB (ie, modem) .. many residential users do
have the 20:1 Ethernet service.

For the benefit of our overseas friends, the services are:

=09512Kbit/sec @ 50:1 contention over the ATM network,
=09this uses a USB modem which uses the Host CPU to=20
=09perform all PPPoA functions.

=09512Kbit/1Mbit/2Mbits @ 20:1 contention over the ATM network,
=09this uses a small router and presents a 10baseT ethernet
=09interface.
=09You get either a NAT or routed IP configuration.

It's worth noting that the USB devices are prone to disconnections when
the host us busy, you must run a specific version of MS Windows .. a linux
driver exists but is apparently unreliable.

It's also worth noting that the Routers supplied for the ethernet services
are prone to overheating ang lockups. They have inadequate ventilation and
cooling ... many people who install these in machine rooms or equipment
racks have no end of troubles.

At present, BT's network is under-subscribed. Once those contention ratios
start to matter, you will see the speed drop.

50:1 on a 512Kb service means that you could get just 10Kbit/sec and still
be getting what you are contractually entitled to. Of course, it will be
costing you more than a permanently nailed up V.90 or ISDN call to an
appropriate ISP with the surftime discount package..

> Is DSL provision on that side of the pond really as bad as everyone says
> it is?  My experience here in .uk has been nothing but good.  This may
> well be because BT spent well over two years testing testing testing and
> debugging everything in sight instead of just rolling it out to make quic=
k
> money.  In the five months I've had it, the service has been very reliabl=
e
> indeed.

This is partly correct and partly incorrect. Much of the BT ADSL service
has been riddled with problems precisely due to a lack of proper
specification, design, and testing, roll-out by people clueful enough to
do so. OTOH such proper specification, design, and testing is one of the
things which traditionally BT do very well. The problem must largely be
due to the external pressures put upon them by whinging customers and the
regulator (Oftel).

Many of the BT staff dealing with ADSL do not have the appropriate
know-how.

That said, where it works it works well if you're fortunate enough not to
encounter any of the many problems which so often arise.

There are still the overriding problems that BT are dragging their feet
installing the DSLAMs in the local exchanges, and dragging their feet even
more in opening up the service to allow ISPs to operate the IP layer
themselves.

Of course, for 99% of the population this service is vapourware and is
likely to be for a long while to come.

I'm currently in-between two ADSL-enabled exchanges - my exchange is not
scheduled to be upgraded. There is no alternative. In an city centre, that
is just appalling.

NTL are just as pathetic. I have NTL ducting up my street (previously
cable and wireless, and before that bell cablemedia). NTL have the ability
to provide me with cable TV and phone service if they wish. They own real
copper in the ground in Leeds. What do they do? .. now if you want a phone
service from NTL they will not provide it themselves.. you get a stupid
prefix-dialler which just prefixes all of your calls with the indirect
access code to get NTL billing over your BT line.

The cable companies here need to pull their finger out, get a clue, and
offer their own service over their own infrastructure. Re-selling BT
services is _not_ competing with BT (and Oftel are fools for thinking it
is).

Cable operators in the UK are perfectly placed to make a difference, but
none of them want to. They have enough coverage and short enough access
tails to provide reliable DSL services to large parts of the population,
and even to start getting fiber to the home... they have existing ducting
up to people's homes! If they did this, BT would have to get DSL available
universally to get any chance of a look-in in that market.

I suspect that the cable operators are waiting for BT to do all of the
expensive R&D, Testing, and approvals applications for the necessary
domestic telecoms service interfaces before they jump in with a copy-cat
service.

Since most cable companies opted for the bargain-basement charging model,
most of them struggle to operate a service, let alone undertake any
development.

BT are too busy trying to maintain a monopoly just by existing, rather
than actually moving forward in any way. Unfortunately the bulk of the
arguments put forward by joe public and Oftel are just as stupid. IMO the
point is not to get adsl everywhere at below-cost and sort-of working, but
to get it everywhere at fair cost and reliable.

Maybe if they'd not wasted =A3billions on uselessly inflated 3G mobile
licenses that are no use to anybody, we'd have some decent terrestrial
telecoms by now?

We are starting to develop, in this country, a business model which says
that nothing actually has to work or be reliable... see cable and wireless
(and many other cable co's for that matter) for example...

I could rant for ages (even more than I already have) on this, but I won't =
:)

d.