It depends on what you mean by KB/sec
Could you define it please?
In detaill?

"Domestos" wrote in message
...
How many KB/sec should i be getting on a 512k standard connection - i'm
currently geting about 42.0 - 45.0KB/sec

Domestos

"will kemp" wrote in message
news
On Wed, 25 Aug 2004 21:45:47 +0000, Domestos wrote:

How many KB/sec should i be getting on a 512k standard connection - i'm
currently geting about 42.0 - 45.0KB/sec

well, if you were to assume 8 bits to the byte, 42 kBps = ( 42 * 8 ) kbps
= 336kbps.

however, that doesn't allow for communications overheads and
packet headers etc. i'm not sure exactly what sort of communications adsl
uses, but a standard modem generally uses 11 bits to transmit one byte
(two start bits and one stop bit). if there are 11 bits to the byte, then
42kBps = 462kbps, which is getting a bit closer to 512. on top of that, i
reckon you could reasonably allow, say, 5% for various network protocol
overheads, which brings you very close to 512kbps.

i consistently get in the high 40s kBps, and peaks of the low 50s, which i
think is fairly reasonable, considering...

Yes it can all get rather complicated and it may depend upon how your
PC is convigured and what protocols it is set up for.

things are never what they seem.


will

In article ,
Clansman writes:
On Thu, 26 Aug 2004 14:10:01 +0100, Shevek
wrote:

On Thu, 26 Aug 2004 04:29:02 GMT, Clansman
wrote:

I've noted what the others have said, vis a vis contention etc.

the easiet way is simply do the math :-

512kbps x 1024 = 524288 bits
524288/8 = 65536 bytes
65536/1024 = 64 KBytes

Erm, not wishing to **** on your fire ;-) but all you need to do is:

512 Kbit/s / 8 (bits per byte) = 64 KBytes/s

No need to multiply by then divide by 1024!

No Problem, I did it the `long' way to show anyone who needed to know how to
do it.

There is a need to multiply by 1000 then possibly divide by 1024. When
talking about bps (bits per second) k, M and G have always had the ISO
meanings of 1000, 10^6 and 10^9 respectively. So 512 kbps always means
512,000 bps. There is only one possible meaning for these multipliers in
the case of data rates in bits per second. A 1 Gbps ethernet runs at
1,000,000,000 bits per second, certainly not 1,073,741,824. A kbps
is always 1000 bps, never, ever 1024 bps.

However, what we're really talking about is ADSL which is stated to be
500 kbps, i.e. 500,000 bps, or 1 Mbps (1,000,000 bps) or 2 Mbps
(2,000,000 bps). Let's leave aside the issue of the actual speed of
the ATM layer it's carried over.

When we talk about bytes there are two meanings of k, M and G when
applied to bytes. Using 1024, 1024x1024 and 1024x1024x1024 has
lived alongside what used to be a lot less common, the use of the
standard ISO meanings (1000, 10^6 and 10^9) bytes. If we want to be
totally correct, we should use kibi, mebi and gibi,
with corresponding symbols Ki, Mi and Gi where we mean 1024,
1024x1024 and 1024x1024x1024 respectively (2^10, 2^20 and 2^30).

The correct calculation is:

500 kbps = 500,000 bits per second
= 500,000/(8 x 1024) = 61.035 kBytes/sec in loose usage
= 61.035 KiBytes/sec strictly
= 500,000/(8 x 1000) = 62.5 kBytes/sec strictly

The above is not concerned with the affects of protocol overheads, which
mean useful data conveyed is always less than the rate of any link which
is also carrying in-band protocol.

See
http://www.gscassociates.com/EDCS_FD...ext/units.html
http://encyclopedia.thefreedictionary.com/kbps
http://encyclopedia.thefreedictionary.com/kibi
for further info.


--
Tim Clark

well, accoring to my router, I'm connected at 576kb/s. I'm on a 512k ADSL to
BT internet.


"Bob Evans" wrote in message
...
In article , chris
wrote
On Thu, 26 Aug 2004 08:31:30 +0100 and in article
, Phil Thompson said...
: On Wed, 25 Aug 2004 23:40:31 +0100, chris wrote:
:
: That's still slow imo. You should get 59k/sec at LEAST.
:
: make your mind up, half an hour ago it was "58-60k/sec"

Pointless post really, you knew what I was getting at. 58k/sec should
be a minimum speed on a 512k connection. I get a speed test rating of
59.6k/sec on my 512k at home and 179.8k/sec on my NTL 1.5mbit.

Perhaps it would be helpful at this point to remind people receiving their
broadband via one of the BT IPStream500 products that the specified
downstream IP data rate is actually 500kbps, not 512.

--
Bob Evans

On Thu, 26 Aug 2004 14:10:01 +0100, Shevek
wrote:

Erm, not wishing to **** on your fire ;-) but all you need to do is:
512 Kbit/s / 8 (bits per byte) = 64 KBytes/s

is there not a protocol overhead to account for ?

if you're getting 512 kb/s of line speed as well as the data you
receive you have tcp/ip headers (28 bytes in 1500) and then FTP or
HTTP stuff going on between the sending and receiving end.

Phil
--
spamcop.net address commissioned 18/06/04
Come on down !

On Thu, 26 Aug 2004 22:11:31 GMT, "Tim Clark"
wrote:

In article ,
Clansman writes:
On Thu, 26 Aug 2004 14:10:01 +0100, Shevek
wrote:

On Thu, 26 Aug 2004 04:29:02 GMT, Clansman
wrote:

I've noted what the others have said, vis a vis contention etc.

the easiet way is simply do the math :-

512kbps x 1024 = 524288 bits
524288/8 = 65536 bytes
65536/1024 = 64 KBytes

Erm, not wishing to **** on your fire ;-) but all you need to do is:

512 Kbit/s / 8 (bits per byte) = 64 KBytes/s

No need to multiply by then divide by 1024!

No Problem, I did it the `long' way to show anyone who needed to know how to
do it.

There is a need to multiply by 1000 then possibly divide by 1024. When
talking about bps (bits per second) k, M and G have always had the ISO
meanings of 1000, 10^6 and 10^9 respectively. So 512 kbps always means
512,000 bps. There is only one possible meaning for these multipliers in
the case of data rates in bits per second. A 1 Gbps ethernet runs at
1,000,000,000 bits per second, certainly not 1,073,741,824. A kbps
is always 1000 bps, never, ever 1024 bps.

However, what we're really talking about is ADSL which is stated to be
500 kbps, i.e. 500,000 bps, or 1 Mbps (1,000,000 bps) or 2 Mbps
(2,000,000 bps). Let's leave aside the issue of the actual speed of
the ATM layer it's carried over.

When we talk about bytes there are two meanings of k, M and G when
applied to bytes. Using 1024, 1024x1024 and 1024x1024x1024 has
lived alongside what used to be a lot less common, the use of the
standard ISO meanings (1000, 10^6 and 10^9) bytes. If we want to be
totally correct, we should use kibi, mebi and gibi,
with corresponding symbols Ki, Mi and Gi where we mean 1024,
1024x1024 and 1024x1024x1024 respectively (2^10, 2^20 and 2^30).

The correct calculation is:

500 kbps = 500,000 bits per second
= 500,000/(8 x 1024) = 61.035 kBytes/sec in loose usage
= 61.035 KiBytes/sec strictly
= 500,000/(8 x 1000) = 62.5 kBytes/sec strictly

The above is not concerned with the affects of protocol overheads, which
mean useful data conveyed is always less than the rate of any link which
is also carrying in-band protocol.

See
http://www.gscassociates.com/EDCS_FD...ext/units.html
http://encyclopedia.thefreedictionary.com/kbps
http://encyclopedia.thefreedictionary.com/kibi
for further info.

Thanks for that Tim, happy to be corrected on matters like this!

--


Shevek

Get DigiGuide - a downloadable desktop PC TV and Radio Guide
http://getdigiguide.com/?p=1&r=31493

Learn how to post? If you are talking about posting at the top of the
message, I prefer to read it that way as well as write it that way.

"chris" wrote in message
...
On Thu, 26 Aug 2004 23:03:05 +0000 (UTC) and in article cglq78$pr0$1
@hercules.btinternet.com, Pete. said...
: well, accoring to my router, I'm connected at 576kb/s. I'm on a 512k
ADSL to
: BT internet.
:
:
Dude, get some clue. And learn how to post.
--
chris

On Fri, 27 Aug 2004 15:17:54 +0000 (UTC), "Pete."
wrote:

Learn how to post? If you are talking about posting at the top of the
message, I prefer to read it that way as well as write it that way.

You vs 95% of Usenet - great attitude!


"chris" wrote in message
. ..
On Thu, 26 Aug 2004 23:03:05 +0000 (UTC) and in article cglq78$pr0$1
@hercules.btinternet.com, Pete. said...
: well, accoring to my router, I'm connected at 576kb/s. I'm on a 512k
ADSL to
: BT internet.
:
:
Dude, get some clue. And learn how to post.
--
chris



--


Shevek

Get DigiGuide - a downloadable desktop PC TV and Radio Guide
http://getdigiguide.com/?p=1&r=31493

On Thu, 26 Aug 2004 22:11:31 GMT, "Tim Clark"
wrote:



There is a need to multiply by 1000 then possibly divide by 1024. When
talking about bps (bits per second) k, M and G have always had the ISO
meanings of 1000, 10^6 and 10^9 respectively. So 512 kbps always means
512,000 bps. There is only one possible meaning for these multipliers in
the case of data rates in bits per second. A 1 Gbps ethernet runs at
1,000,000,000 bits per second, certainly not 1,073,741,824. A kbps
is always 1000 bps, never, ever 1024 bps.

However, what we're really talking about is ADSL which is stated to be
500 kbps, i.e. 500,000 bps, or 1 Mbps (1,000,000 bps) or 2 Mbps
(2,000,000 bps). Let's leave aside the issue of the actual speed of
the ATM layer it's carried over.

When we talk about bytes there are two meanings of k, M and G when
applied to bytes. Using 1024, 1024x1024 and 1024x1024x1024 has
lived alongside what used to be a lot less common, the use of the
standard ISO meanings (1000, 10^6 and 10^9) bytes. If we want to be
totally correct, we should use kibi, mebi and gibi,
with corresponding symbols Ki, Mi and Gi where we mean 1024,
1024x1024 and 1024x1024x1024 respectively (2^10, 2^20 and 2^30).

The correct calculation is:

500 kbps = 500,000 bits per second
= 500,000/(8 x 1024) = 61.035 kBytes/sec in loose usage
= 61.035 KiBytes/sec strictly
= 500,000/(8 x 1000) = 62.5 kBytes/sec strictly

The above is not concerned with the affects of protocol overheads, which
mean useful data conveyed is always less than the rate of any link which
is also carrying in-band protocol.

See
http://www.gscassociates.com/EDCS_FD...ext/units.html
http://encyclopedia.thefreedictionary.com/kbps
http://encyclopedia.thefreedictionary.com/kibi
for further info.

Thanks for that. I'm always happy to learn something new, much appreciated.

Clansman