DataStream v IPStream

Anyone care to clarify exactly the difference between the 2 for me. Have
done some reading, but other people's interpretation always add value.

Cheers

On 2004-05-07, b0yce <b0yce@.> wrote:
> Anyone care to clarify exactly the difference between the 2 for me. Have
> done some reading, but other people's interpretation always add value.
>
Datastream's back end virtual path is different to that of IP stream.
That's about all I specifically know i'm afraid. Tried google groups?

If not, i'm sure someone here knows rather more than me about this

--
chris

"chris" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> On 2004-05-07, b0yce <b0yce@.> wrote:
> > Anyone care to clarify exactly the difference between the 2 for me. Have
> > done some reading, but other people's interpretation always add value.
> >
> Datastream's back end virtual path is different to that of IP stream.
> That's about all I specifically know i'm afraid. Tried google groups?
>
> If not, i'm sure someone here knows rather more than me about this

Wish it were me that knew it. But, I just cut-n-paste from the ever
excellent adsguide.org.uk!!


http://www.adslguide.org.uk/qanda.as...beginners#Q259
Which is better, IPStream or DataStream?
Neither IPStream nor DataStream is 'better' necessarily. These are both BT
Wholesale provided services but they deliver the connection to the ISP in a
different way.

IPStream is a service where the user traffic is routed longer inside BT's
managed network whereas with DataStream, the ISP takes one or more 'virtual
path' (VP) circuits to each local exchange so they can manage contention
themselves.

Most ISPs use DataStream to deliver services with high contention ratios
spread over very small numbers, so often DataStream will deliver worse
performance, however technically it is capable of more customised services,
including 1:1 contention. Therefore, you should not choose a service solely
because it uses IPStream or DataStream but look into user experiences of the
particular service. DataStream's advantage in the current market is for
ultra low cost services, or low contention / uncontended services or where
Quality of Service (QoS) is needed.



See also http://www.adslguide.org.uk/qanda.asp?faq=technical
which also makes reference to DataStream and IPStream.

My favourite part being:
"BT DataStream with In Span Handover
The 1Mbps and 2Mbps low price products... use a different system for
contention. How this contention is controlled is down to the individual
service provider. While a similar system is used to the BT IPStream product
ranges, due to the costs the ISPs generally rent the minimum amount of
bandwidth needed from BT Wholesale. ... the result of this is that
Datastream users often see higher levels of contention, the penalty for the
lower price of Datastream products in general."



Key phrase being 'rent the minimum amount of bandwidth needed from BT'.

If I knew as much about this, and about LLU, prior to joining Bulldog
Communications on PrimeTime 2000, I never would have left BT - And it shocks
me to think/say that.

I have between two & four times the bandwidth during the day when on
512Kbps, than I have in the evenings when on 2Mbit! Work that one out.

Baz