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Re: [News] [Rival] Microsoft Windows Zombies Emit Well Over 100,000,000,000 SPAM Per Day

Homer <usenet@xxxxxxxxxx> espoused:
> Verily I say unto thee, that bbgruff spake thusly:
>> The Ghost In The Machine wrote:
>>> In comp.os.linux.advocacy, bbgruff <bbgruff@xxxxxxxxxxx> wrote on
>>> Tue, 12 Aug 2008 23:43:31 +0100
>>>> The Ghost In The Machine wrote:
>
>>>>> [+] I pay $40 per month for a 1.5Mb/s ISDN connection.  There 
>>>>> are cheaper plans, I'm sure.
>>>> 
>>>> You really meant to type that?
>>>> 
>>>> Curious:-)
>> 
>> (snip)
>> 
>>> I probably should have said DSL instead of ISDN.
>> 
>> (snip)
>> 
>> Thanks G - *that* was the question! I was just wondering there if you
>> guys had got some new-fangled version of ISDN:-)
>
> Theoretically one could bond 24 64Kb ISDN channels to achieve 1.5Mb/s
> the really hard (and expensive) way, I suppose. Also I believe that each
> line only supports 128k ISDN2e, so he'd need to have 12 phone lines too.
> In UK (BT) price terms, that's 12 line rentals @ £10.50/month, plus 12
> ISDN2e subs @ £97.47/quarter, plus the cost of calls (no flat rate like
> ADSL), plus VAT @ 17.5%. That's £7,273.91/year ($13,573.21) including
> VAT, but excluding the cost of calls, which according to my experience
> might easily be around £1000.00/quarter for a heavily used line, giving
> a conservative rounded total of around 10 grand UK (20 grand US) a year.
>
> Ouch!

Why on earth would you do it that way...

Surely, you'd just take an E1 if you wanted streaming, or a Wan product
if all you want is best effort packet?

An E1 would be somewhere between £600 and £1,300 pcm, at least according
to a web site I looked at a moment ago.   This would give you
2048kbit/s, always on.  This comes to £7,200 per year to £15,600 per
year.  

Even if you wanted a lot of lines as individual ISDN lines, surely you'd
go for ISDN30, so you have only one access line?

There are less expensive ways of getting bandwidth than an old-style
leased line, though.  "managed communications" claim to offer wan
services which come in at about ½ the cost of leased lines, so
presumably, this could be down to £3,500 per year?  

Now, I've just taken a look here:
http://www.productsandservices.bt.com/btbusinessProducts/displayProduct.do?productId=BTB-5088

and I see that ISDN30 rental starts at £54.57 + vat for rental, per
quarter.  All BT's prices are up on its website (ofcom requirement)
for services where BT has "significant market power", so you don't need
to guess, you can just look them up.  In any case, that means that the
rental figure you quote above is, by my quick calculation, around £6,000 per
year too high.

ISDN call charges, again according to the price list, range from 0.85
pence per minute for weekend off peak up to 7.9ppm for national peak
rate.  To get £1,000 per quarter in call charges, you'd need to be
making 12,600 minutes of calls per quarter, all in peak time, or almost
27 days of constant peak-time calling, to national numbers, to get there.

If you're really making that many calls *to the same number*, then it's
most likely that some kind of leased line solution will be much less
expensive, as your're just tieing up the switched network all day, every
day.

If this is for internet dial-up, then I would think that you'd be
getting a local rate, which would be much less expensive, but I don't
know for sure.

>
> Compare that to the cheapest (that I could find) ADSL price in the UK
> (Sky Broadband) @ £5.00/month or £60/year ($112), for 8*Mb/s*.
>
>> Now (just for comparison) I get 8Mb down, 1.2 Mb up for (converting)
>> $28, and the option of "up to 24Mb" down for about $37, but I doubt
>> I'd get much more than 8Mb if I opted for it (line condition and 
>> distance), so I just go with the cheaper.  All "unlimited bandwidth",
>> but a "fair use" clause.
>
> Our 21CN PSTN switchover target is supposed to be Q3 2011. Until then
> I'll have to "make do" with 8Mb/s.

You can always have an additional ADSL line, if you need additional
bandwidth.

One thing to consider, of course, with ADSL, is the contention rate.
You don't actually get 8Mbit/s, constantly, guaranteed to any
destination, what you actually get is up to 8Mbit/s of access into the
wider internet, shared with probably up to 30 other users, who might
also want the same access rates...  the whole thing works on the
assumption that consumption of IP networks is, well, statistically
muxable.  Of course, this only works to a point, as like in the case of
the PSTN, we get busy-hours.

For ADSL2+, the maximum rate should rise up to 24Mbit/s, but obviously
this will depend on normal transmission line issues, including length of
the line, condition of the line and so on.  You canna change the laws of
physics.

The presently mooted plan to do fibre to the kerb (see recent news)
could bring as much as 100Mbit/s to every house, but again, you'd need
to look at contention ratios and the economics of the whole thing - it
doesn't come free.

>
>> While I have your attention, may I ask what you guys pay typically 
>> for a telephone line and national calls?  In fact, considering the 
>> size of the U.S., perhaps we ought to say "unlimited calls withing 
>> the state!"?
>
> It'd be interesting to see if the 20k figure above is accurate, or
> merely representative of "Rip-Off Britain".
>

It's just not a particularly inexpensive way of solving the problem.
Switched ISDN ties up one line card per 64kbit/s channel, so if you really
wanted 24 channels, then you are using, 24x7, 24 line cards at the switch,
and as it's ISDN, there is additional signalling capacity which you're
presented with, so that you can set up eg., video conferencing calls by
bonding the channels.

On ISDN30 connections, each timeslot (64kbit/s channel) is guaranteed
to take the same route on any call either nationally or internationally
so that any bonding equipment in use can assume that bits sent in order
will arrive in order at the distant end.  Furthermore, the calls are
guaranteed to meet G.114 delay requirements, ie., not exceed 400ms
round-trip delay to any destination, with error performance meeting G.826,
and maintenance to M.2101 parts 1 and 2.

The whole thing is designed to guarantee *streaming* performance
globally, and it works well indeed.  It is, however, taxing on equipment
requirements, network designs & limitations, and frankly very expensive
to build and to maintain.

If all you want is some best-effort bandwidth, then ISDN is massively
over-specified, and so will certainly seem very expensive.  It's a bit
like taking a Rolls Royce off road...  or trying to use a Landrover in a
F1 race.  It's just the wrong tool for the job.  Unless you have a PBX
and multiple sites around the world with other PBXs, or want to do
international video conferencing, of course.

Now, if you want some *serious* bandwidth, you could take a look at
"Wavestream".
http://www.serviceview.bt.com/list/public/current/DWDM_Wavelength_Svc_boo/1435_d0e5.htm#1435-d0e5



-- 
| mark at ellandroad dot demon dot co dot uk                           |
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| Cola trolls:  http://colatrolls.blogspot.com/                        |
| Open platforms prevent vendor lock-in.  Own your Own services!       |


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