Newbie question on bandwidth

Hello,

I am confused about how much bandwidth a 2MB/s leased line link actually
provides. Sometimes it is also written as 2Mbps. Is it 2 megabytes or 2
megabits per second ? If it is 2 megabits/s, is there any other advantage
over ADSL than just being able to also upload at higher speeds and no
contention ? Prices for leased line certainly are exorbitant.

Sorry for posting this here, I am just not sure where to post it.

--

Regards,
Mark

PLEASE DO NOT REPLY DIRECTLY TO THE EMAIL ADDRESS FOR OBVIOUS REASONS. REPLY
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On Thu, 09 Oct 2003 02:09:34 +0100, News wrote:

> Hello,
>
> I am confused about how much bandwidth a 2MB/s leased line link actually
> provides. Sometimes it is also written as 2Mbps. Is it 2 megabytes or 2
> megabits per second ? If it is 2 megabits/s, is there any other advantage
> over ADSL than just being able to also upload at higher speeds and no
> contention ? Prices for leased line certainly are exorbitant.
>
> Sorry for posting this here, I am just not sure where to post it.
>
> --
>
> Regards,
> Mark

Computes tend to express data transfer rates in bytes. Line systems tend
to express their speed in bits.

A 2 meg system delivers 2 million bits per second which is 250 kilo bytes
per second ie. 2000/8 because there is 8 bits in a byte.

hope this helps, Graham.

"News" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> Hello,
>
> I am confused about how much bandwidth a 2MB/s leased line
link actually
> provides. Sometimes it is also written as 2Mbps. Is it 2
megabytes or 2
> megabits per second ? If it is 2 megabits/s, is there any
other advantage
> over ADSL than just being able to also upload at higher
speeds and no
> contention ? Prices for leased line certainly are
exorbitant.

it's usually megaBITS/second. Leased lines are usually,
though not always, point to point connections, 1:1
contention, unlike ADSL which can be anything from 20:1 to
50:1

P.

And leased lines usually have a SLA, whereas xDSL don't. Depends on if the
line is critical to you business.

--

(¯`·._.· All Outgoing Mail Scanned With Norton Anti-Virus 2003 ·._.·´¯)



PJB wrote:
> "News" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed)...
>> Hello,
>>
>> I am confused about how much bandwidth a 2MB/s leased line link
>> actually provides. Sometimes it is also written as 2Mbps. Is it 2
>> megabytes or 2 megabits per second ? If it is 2 megabits/s, is there
>> any other advantage over ADSL than just being able to also upload at
>> higher speeds and no contention ? Prices for leased line certainly
>> are exorbitant.
>
> it's usually megaBITS/second. Leased lines are usually,
> though not always, point to point connections, 1:1
> contention, unlike ADSL which can be anything from 20:1 to
> 50:1
>
> P.

"eusty" <(E-Mail Removed)> wrote in message
news:3f85093b$0$65584$(E-Mail Removed) ...
> And leased lines usually have a SLA, whereas xDSL don't. Depends on if the
> line is critical to you business.

Just because there is an SLA doesn't make it more reliable. One of
our customers has a leased line, another one used to. Both proved
far less reliable than any of the 50 or so ADSL lines that are in use
by our customers now.

"Alastair" <(E-Mail Removed)> wrote in message
news:3f8513d7$0$15131$(E-Mail Removed) t...
> "eusty" <(E-Mail Removed)> wrote in message
> news:3f85093b$0$65584$(E-Mail Removed) ...
> > And leased lines usually have a SLA, whereas xDSL don't. Depends on if
the
> > line is critical to you business.
>
> Just because there is an SLA doesn't make it more reliable. One of
> our customers has a leased line, another one used to. Both proved
> far less reliable than any of the 50 or so ADSL lines that are in use
> by our customers now.

But a SLA will mean that if it fails, you get it fixed. A friend had his
ADSL out from last night until about 11am this morning - as we run
mail/DNS/www on-site, if that was ADSL, we'd be annoyed if it was out that
long - especially as with ADSL, BT have no contracted obligation to fix it
within X hours.

Obviously though, you pay for it. £13k for a 2 meg leased line (+ £2k
setup) isn't cheap - but we've only had 2 outages in 2 years, one about 1.5
hours and another less than 30 minutes. My friend has had 2 or 3 outages in
the month that he's had ADSL!

D

"David Hearn" <(E-Mail Removed)> wrote in message
news:bm3ls3$j81$(E-Mail Removed)...
>
> "Alastair" <(E-Mail Removed)> wrote in message
> news:3f8513d7$0$15131$(E-Mail Removed) t...
> > "eusty" <(E-Mail Removed)> wrote in message
> > news:3f85093b$0$65584$(E-Mail Removed) ...
> > > And leased lines usually have a SLA, whereas xDSL don't. Depends on if
> the
> > > line is critical to you business.
> >
> > Just because there is an SLA doesn't make it more reliable. One of
> > our customers has a leased line, another one used to. Both proved
> > far less reliable than any of the 50 or so ADSL lines that are in use
> > by our customers now.
>
> But a SLA will mean that if it fails, you get it fixed. A friend had his
> ADSL out from last night until about 11am this morning - as we run
> mail/DNS/www on-site, if that was ADSL, we'd be annoyed if it was out that
> long - especially as with ADSL, BT have no contracted obligation to fix it
> within X hours.

An SLA doesn't guarantee that you will get it fixed. It does mean that you
will get some compensation if they fail to fix it within a certain time, the
amount that you get though is generally irrelevant if you are a business.

> Obviously though, you pay for it. £13k for a 2 meg leased line (+ £2k
> setup) isn't cheap - but we've only had 2 outages in 2 years, one about
1.5
> hours and another less than 30 minutes. My friend has had 2 or 3 outages
in
> the month that he's had ADSL!

Your friend has clearly had a bad experience. We average one or two
outages per year of a few minutes each duration on all of the ADSL
lines we or our customers have.

"Alastair" <(E-Mail Removed)> wrote in message
news:3f854e29$0$15126$(E-Mail Removed) t...
> "David Hearn" <(E-Mail Removed)> wrote in message
> news:bm3ls3$j81$(E-Mail Removed)...
> >
> > "Alastair" <(E-Mail Removed)> wrote in message
> > news:3f8513d7$0$15131$(E-Mail Removed) t...
> > > "eusty" <(E-Mail Removed)> wrote in message
> > > news:3f85093b$0$65584$(E-Mail Removed) ...
> > > > And leased lines usually have a SLA, whereas xDSL don't. Depends on
if
> > the
> > > > line is critical to you business.
> > >
> > > Just because there is an SLA doesn't make it more reliable. One of
> > > our customers has a leased line, another one used to. Both proved
> > > far less reliable than any of the 50 or so ADSL lines that are in use
> > > by our customers now.
> >
> > But a SLA will mean that if it fails, you get it fixed. A friend had
his
> > ADSL out from last night until about 11am this morning - as we run
> > mail/DNS/www on-site, if that was ADSL, we'd be annoyed if it was out
that
> > long - especially as with ADSL, BT have no contracted obligation to fix
it
> > within X hours.
>
> An SLA doesn't guarantee that you will get it fixed. It does mean that you
> will get some compensation if they fail to fix it within a certain time,
the
> amount that you get though is generally irrelevant if you are a business.
>
> > Obviously though, you pay for it. £13k for a 2 meg leased line (+ £2k
> > setup) isn't cheap - but we've only had 2 outages in 2 years, one about
> 1.5
> > hours and another less than 30 minutes. My friend has had 2 or 3
outages
> in
> > the month that he's had ADSL!
>
> Your friend has clearly had a bad experience. We average one or two
> outages per year of a few minutes each duration on all of the ADSL
> lines we or our customers have.

Well, see the thread above this one about Virgin/PlusNet etc being out for a
number of hours (my friend was caught in this one too), and you'll also find
a number of other messages in this group asking whether X ISP is out
everywhere etc. I would say that my friend has probably had a slightly bad
experience, but your customers are probably having very fortunate
experiences of ADSL.

Whilst I agree that SLA's are little reassurance when they're down - they do
tend to reassure people that there is someone at the other end of the line
monitoring things. We've had NTL (provider of our leased line) phone us up
to apologise for a problem on the line we never noticed! With ADSL you just
get "its a national problem with BT" and little other information. Why do
you think that BT don't provide SLA's - even on their business ADSL lines?
Its probably because if they did, they'd be paying out too much in
compensation.

Its bad enough when I get 30 people phoning me up when something stops
working (and I've warned them about it) - let alone having to tell them that
BT's to blame and I've no idea when it'll be back.

Still, at £40 a month you can't really complain. Would beat our £1k a month
quite significantly. If you don't mind possible outages for possibly couple
of hours at a time, then pay £40 a month. But for us, we've decided we'd
rather no problems than risk it (we've tried a cheaper, non-leased-line
option before and pulled out before the end of the first month of the 3
month trial because it would die often and for an hour or so at a time).

D

"David Hearn" <(E-Mail Removed)> wrote in message
news:bm4no5$ok3$(E-Mail Removed)...
>
> "Alastair" <(E-Mail Removed)> wrote in message
> news:3f854e29$0$15126$(E-Mail Removed) t...
> > "David Hearn" <(E-Mail Removed)> wrote in message
> > news:bm3ls3$j81$(E-Mail Removed)...
> > >
> > > "Alastair" <(E-Mail Removed)> wrote in message
> > > news:3f8513d7$0$15131$(E-Mail Removed) t...
> > > > "eusty" <(E-Mail Removed)> wrote in message
> > > > news:3f85093b$0$65584$(E-Mail Removed) ...
> > > > > And leased lines usually have a SLA, whereas xDSL don't. Depends
on
> if
> > > the
> > > > > line is critical to you business.
> > > >
> > > > Just because there is an SLA doesn't make it more reliable. One of
> > > > our customers has a leased line, another one used to. Both proved
> > > > far less reliable than any of the 50 or so ADSL lines that are in
use
> > > > by our customers now.
> > >
> > > But a SLA will mean that if it fails, you get it fixed. A friend had
> his
> > > ADSL out from last night until about 11am this morning - as we run
> > > mail/DNS/www on-site, if that was ADSL, we'd be annoyed if it was out
> that
> > > long - especially as with ADSL, BT have no contracted obligation to
fix
> it
> > > within X hours.
> >
> > An SLA doesn't guarantee that you will get it fixed. It does mean that
you
> > will get some compensation if they fail to fix it within a certain time,
> the
> > amount that you get though is generally irrelevant if you are a
business.
> >
> > > Obviously though, you pay for it. £13k for a 2 meg leased line (+ £2k
> > > setup) isn't cheap - but we've only had 2 outages in 2 years, one
about
> > 1.5
> > > hours and another less than 30 minutes. My friend has had 2 or 3
> outages
> > in
> > > the month that he's had ADSL!
> >
> > Your friend has clearly had a bad experience. We average one or two
> > outages per year of a few minutes each duration on all of the ADSL
> > lines we or our customers have.
>
> Well, see the thread above this one about Virgin/PlusNet etc being out for
a
> number of hours (my friend was caught in this one too), and you'll also
find
> a number of other messages in this group asking whether X ISP is out
> everywhere etc. I would say that my friend has probably had a slightly
bad
> experience, but your customers are probably having very fortunate
> experiences of ADSL.

I think it's probably not so much a matter of fortune but one of research
and planning. Before settling on the ADSL ISP that we use ourselves and
that we recommend to our customers we spent ages reading the newsgroups,
contacting reference customers, running tracerts, making test calls to
support
lines and so on. The ISP we eventually chose (AAISP) were by no means the
cheapest, but they did seem to have the right attitude and the right track
record. They haven't let us down yet.

> Whilst I agree that SLA's are little reassurance when they're down - they
do
> tend to reassure people that there is someone at the other end of the line
> monitoring things. We've had NTL (provider of our leased line) phone us
up
> to apologise for a problem on the line we never noticed! With ADSL you
just
> get "its a national problem with BT" and little other information. Why do
> you think that BT don't provide SLA's - even on their business ADSL lines?
> Its probably because if they did, they'd be paying out too much in
> compensation.

Again though, a good ISP may provide a better service without an SLA.
AAISP ping all of our connections once a second and on the rare occasion
that something does go wrong generally know about it and are working on the
problem before we or our customers even notice. If we want them to they
will even send us an SMS if a line goes down. This is in stark contrast with
our experience with leased lines. I daresay there are some good, responsive,
efficient leased line providers, but we haven't come across them yet.

> Its bad enough when I get 30 people phoning me up when something stops
> working (and I've warned them about it) - let alone having to tell them
that
> BT's to blame and I've no idea when it'll be back.

> Still, at £40 a month you can't really complain. Would beat our £1k a
month
> quite significantly. If you don't mind possible outages for possibly
couple
> of hours at a time, then pay £40 a month. But for us, we've decided we'd
> rather no problems than risk it (we've tried a cheaper, non-leased-line
> option before and pulled out before the end of the first month of the 3
> month trial because it would die often and for an hour or so at a time).

You've obviously had a bad experience. With a combined connection time
of several 10s of years to AAISP ADSL lines we haven't so are currently
quite happy. Particularly (as you mentioned) given the price difference.