Pull the power cord, wait 30 seconds, plug back in.

Based on the log and your recount of the speedtest, you have latency issues. What this means is when his PSP is attempting to speak to another person's PSP it times out and the connection is severed.

Based on those speeds I assume you are on aDSL, be sure to power cycle all equipment related to this. If you have a DSL modem and a wireless router, pull the plug on both, wait 30 seconds, plug in the DSL modem, wait 2 minutes (or for all lights to be green etc), and then plug in the wireless router.

While not precise, you can generally diagnose your own latency issues by watching the needle in a speedtest. If it goes up and then stays at max, you are good. If it bounces, you have latency.