[plug] modem connect statistics

[Matt Kemner]

On Mon, 21 Aug 2000, Bret Busby wrote:

> Thanks for the statistics, Matt. They are very useful. But, one point;
> could you advise, apart from the connection speeds (capability, or,
> potential), what the transmission speeds (actual) are like?

Other than the first Paragraph, all other numbers I gave you are
_current_ speeds of the modems in question.

This means that those people currently connected at 50666 should get a
sustained transfer rate of around 6k when downloading from a WASP Server
or anywhere in WAIX, and at this time of day, probably most U.S. sites
also. (I tend to get 20-30k/s to my work computer during the day, so I
don't see any reason why a modem user wouldn't be able to get the maximum
speed their modem can handle at the time)

> There are
> three figures here, I suppose; capability figures, and, one actual
> figure. The two capability figures, are the modem speeds and the connect
> speeds

Not just connect speeds. I have seen a modem connect at 50k, and retrain
down to 14.4k within a matter of minutes.  All the customer could see is
that they connected at 50k, so couldn't work out why their downloads were
so slow, but the digital modems told me it had retrained down (which btw
they would have been able to see on their WASP stats page)

> other factors, that are independent of the connect speed (such as
> congestion at the ISP, and, congestion and traffic load, at every point
> from there to the websites being accessed, and back again).

If you primarily try to download from the U.S. during those times most
ISPs (and in fact most of the Australian backbone) are congested then it's
pointless getting a faster modem.  On the other hand a large proxy server
at the ISP does help in that regard - if most of the pages you access are
on the proxy, then the only bottleneck is your modem, so a faster modem
does help. Also, if most of your traffic is via the WAIX then your modem
should be the only bottleneck.  If not, change ISPs.

> certain rate is one thing, but, is there any real advantage in the
> transmission rates, between the two modem speeds (of 33600 and 56k)?

Yes, you will get almost twice the speed out of a 56k modem, compared to a
33.6, providing you either download during non-congested times, or
download from a local site otherwise.

To jump back to your analogy, you could feasibly drive a Ferrari across
the narrows bridge at 150km/h+ outside of peak hours (ie you'd probably be
fine during the day) but you'd have no chance at 8:30am or 5:30pm

On the other hand you'd probably have no trouble driving that fast between
say Midland and Forrestfield (along the Roe Hwy) at any time of day.
 
> Do your stats give the variance of the transmission (especially, the
> download) rates? If for example, statistics could be given, like a mean
> speed of 41333, with a standard deviation of 2000, would mean that 68%

[SNIP more statistics-speak]

This brings back bad memories from my year 12 statistics class..*sigh*

I can give you the raw data if you want and you can work it out for
yourself.

btw I still use a 28.8k modem at home, but that's because I do most of my
downloading at work, and mainly read email from home.

 - Matt