On Tue, 7 Aug 2001, L.D. Best wrote:
> Clarence,
>
> I cannot believe you actually believed you would get the promised speeds
> of DSL. :>
When I signed up, my cable provider promised 256kbps
down and 128kbps up. I was getting better than that.
Then when they changed from Speedway to Metrocast, that
was upped. Advertised rates now are 512/256.
As that NASA photo download shows, I sometimes can
get somewhere in the neighborhood of 1 mbps download;
twice what I'm promised.
> * The primary determinent of download speeds is the server you are
> downloading from!
I don't know that I'd say that's THE PRIMARY,
since route between server and your browser is
probably even more important.
Even if the server is capable of serving you
1 mbps right now, it doesn't do you a bit of good
if there's a router between you and it with a
bottleneck of 100kbps. That's all you're going
to get; roughly 10K/sec.
> Remember, my cable modem/NIC combo [10T] is CAPABLE of 10Mbs, which
> means that theoretically I could download that JPG in 2-3 tenths of a
> single second.
Except you said "T1 or better."
T1 is, IIRC, 1.4 Mbps.
> Instead I got a transfer rate of 15,964 bytes per
> second.
That's barely better than two-channel ISDN. (128kbps)
[I decided to avoid bps because I can remember some sort of
> broughhaha about the b being bits and were they 7 or 8 per byte or ???
Yup... a byte is sometimes 10 bits... and sometimes
it's 9 bits, and usually it's 8 bits. That's the
reason the bit is used for designating bandwidth. It's
a fixed unit of data, while a "byte" is a wiggly word
when used in the context of telecommunications.
In programming, I think "byte" always means 8 bits,
and in ppp I think a byte is also 8 bits, but
download speeds might be skewed by packet overhead.
> Is my modem broken? Do I need a new NIC? ... nah Just have to stop
> expecting fast access from slow servers. :>
I don't know... that seems like a pretty fast server
to me. Just tried again at a "peak" time of 7:14 pm
EDT, and still got the photo in 0:25.
> P.S. Putting in a "faster" NIC wouldn't make much difference; the speed
> is limited by the DSL modem, just like my speed is limited to
> 10Megabytes per second by my cable modem.
You mean megaBITS per second.
> I say that with some
> assurance, since I asked one of the techs if I could speed up things
> with a faster NIC...
Except that if there's a T-1 somewhere between you
and "the world," you're limited to its top speed of
1.4 mega-BITS-per-second.
- Steve
