[OT-ish] How big is the UK 'net?

[Roland Perry]

In message <B93DC188.1FED2%zenadsl6186@zen.co.uk>, Peter Fairbrother 
<zenadsl6186@zen.co.uk> writes
>As some of you know, I've been working on computational anonymity for email
>for a while. I am wondering what a practical limit for per-user bandwidth
>would be, and if anyone could advise, off-list if appropriate.
>
>I have now (in theory) got the traffic down to a few 100MB per customer per
>day, that's for 1 million customers sending up to 40 emails per day each. :)
>
>While that's not a lot for the individual user with broadband, and is just
>about manageable even with dialup although it would hog nearly all the
>dialup bandwidth, it comes to a few 100 TB/day in total. How would the net
>stand up to that increase overall?

A few sums on the back of an envelope say that's 20Gbit/sec, or about 
the current operational rate of LINX. So that would be a significant 
extra load on all the customer networks. But you probably knew that 
anyway. A million dial-up customers running flat out all day isn't 
exactly going to give the other nineteen million very many modems to 
play with, let alone bandwidth!

>Contention issues?

It looks to me as if the long term average bitrate is about 50K per user 
(over an extended working day), which I guess would easily max out 512K 
@ 50:1 if a large number of those users subscribe.

>I'd envisage most of
>the traffic being in the UK only.

That would reduce the international transit bill!

>How much would it cost the single central server for the connectivity?

Hmm, 20Gig of transit.... Sounds to me more like a proposition for 
setting up a dedicated ISP with many peering relationships.

> The
>server itself would cost around £10 million, how much do you think people
>would pay for truly anonymous email?

Not much, judging by PGP.

>How many people have broadband?

Oftel's figures for May say 328K cable modems and 211K ADSL. That's 3.5% 
of homes with Internet and 5% of businesses with Internet. Looking at 
the Oftel charts, that might double in the next 12 months.

-- 
Roland Perry