Port numbers and traffic data

[Andrew Bangs]

--- On Mon, 28/4/08, Ian Batten <igb@batten.eu.org> wrote:
>=20
> Hard to see why: the contention ratio is tunable based on
> how much =20
> backhaul they buy without any need to unbundle.  That's
> a purely =20
> commercial decision.  I don't think ISPs are even
> constrained to just =20
> the 20:1 and 50:1 BT offer; I believe that if they want to
> buy a 1:1 =20
> match between IP Central and IP Stream bandwidth then,
> subject to =20
> there being enough uplink on the DSLAM (which might be an
> issue on =20
> older kit which only has STM-1 uplinks), they're in
> clover. =20


It's even easier to tune contention, especially for very low contention pro=
ducts down to 1:1, on Datastream rather than IPStream. The part of the solu=
tion that's different in order to allow this is that with Datastream the IS=
P is buying capacity (an ATM VP) to an individual DSLAM within an exchange =
rather than buying capacity (an IPStream Central) into an amorphous cloud t=
hat doesn't relate individual subscribers to individual exchanges. The ISP =
can then choose to put multiple customers (as ATM VCs) into the VP in such =
a way that the ratio of the sum of the sizes of the VCs to the size of the =
VP is the contention ratio. (I simplified that a bit - it gets complicated =
when you look at mixing customers of different 'contentions' in the same VP=
.)

Demon and others have offered 1:1 products this way for ages; Vaioni have j=
ust launched some. I wonder if any consumers could be persuaded to take a f=
resh look at their expectations for a =A310 service when confronted with th=
e pricing of a 1:1 offering.=20

Vaioni's pricing is reported on the Thinkbroadband site, here:

http://www.thinkbroadband.com/news/3528-vaioni-launch-uncontended-business-=
dsl.html


--=20
Andrew Bangs=0A=0A=0A      ________________________________________________=
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