network actual bitrate (application level, tcp packet level)

When I say that my network bandwidth is 10kbps, does that refer to the
application layer byte usage speed or the tcp layer speed? In other
words, if my I transmit a file of size 10 kbit and it takes 1sec, is my
speed 10 kbps or should it be more (including the tcp headers,
retransmission overheads, etc)?

Nirnimesh

First of all 10kbps means 10 kiloBITS per second, not 10 kilobytes per
second which is written 10 KBps. That is a common source of confusion.

Now, the answer to that question is neither. Its meaning lays in the
physical layer. That is why a 33kbps cable modem (slowed thown by means
of software) is faster than a 56kbps (40 kbps, really) telephone modem.
The raw speed (from which you must still substract the TCP/IP headers
and protocol data) of the modem is 4.0KBps, since you have 1 stop and 1
parity bit that consume part of your throughput. While the raw speed
of our cable modem is 4.1KBps.

Hope this helps,

Victor Rafael Rivarola