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cnolte
Feb 27, 2009, 01:17 PM
Hi there
I have got a dial-up connection and to download something goes at about 4kb/s.
Is this normal or is my computer or service provider responsible ?
Thanks for your help
Claus

Scleros
Feb 27, 2009, 03:51 PM
Dialup connections using v.90 or v.92 compliant analog modems have a theoretical downstream maximum bandwidth of around 56 kilobits per second, or 56/8 = 7 kiloBytes per second (8 bits = 1 Byte). Phone lines usually aren't perfect enough to achieve this maximum, so connections are typically in the 40-50 kbps range or less which is 5-6 kBps. When protocol overhead is then considered, actual real throughput can indeed be around 4 kBps. However, if you meant 4 kilobits per second, then yes, you have a severe problem.

KISS
Feb 27, 2009, 06:43 PM
Watch the b's and the B's. b is a bit and B is a byte.

For dial-up a character takes up 10 bits. 1 start, 8 bits and 1 stop bit, so there is a lot of overhead.

In order for a 56 K modem to work at max speed, you need an ISDN line at the other end.