dialup problem ??

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dialup problem ??

Tim McClelland
The dialup problem 
When we use openssl over a dialup, our application fails to use all the bandwidth. This seems to be due to that the "next" packet is not sent until the ACK is received for the previous packet. With a relatively high RTT (Round Trip Time) on dial up, there is a large time chunk in which data could be sent, but is not, due to this limitation introduced by our implementation of openssl.

When using a dial up modem to a dialup modem, 33k is the link speed in both directions. Without openssl, our software uses 100% of this bandwidth if needed. However, once we introduce openssl we can only use approx 17k (approx 50%) of the 33k link, even if we need all 33k.
Somewhere, there seems to be a "one packet at a time" limitation introduced. This is an assumption, as to the problem, but by using a packet sniffer to watch the traffic, it does seem to fit the problem.
 
Any suggestions as to what we might be doing wrong?
 
Cheers
Tim