Q3: How can I determine my connection speed?

You want to tell your modem to generate the DCE connection speed, typically by adding 'ATW2' to the modem initialisation sequence (eg in your chatscript) - see your own modem manual in case your command set is slightly different. Then make sure that 'chat' reports the connection speed (add REPORT CONNECT to your chatscript). Finally, make sure that information generated by REPORT is sent to a file, using the -r option to chat. You can then extract it at your leisure…!

Connection speed should be pretty stable, once your system is set up properly. It will depend most on your modem & telephone line. In my case, with lots of phone extensions on the line, the modem a long way from the main socket, and a cheap modem, my connection speed statistics (roughly since August 1999) look like this:

2155 connects, best 48000, worst 2400, average 43546.42, most recent 44000