The original article is a bit unclear on this, but the command was not directly received from a TCP connection initiated by the botnet owner.

Rather, his server connected to some IRC server and joined a channel with all his other bot friends. The owner then sent the command to the IRC channel, and it is then broadcasted to all bots by whatever IRC server he is using.

(This is why lots of IaaS providers will forbid you from hosting an IRC server, and sometimes block all IRC traffic (by port anyway) on their networks)

I don't think it measures the inbound/outbound bandwidth - especially over UDP. It's more of an SSH emulator (so to speak) with everything being logged (commands, files, etc.).

In addition, there are quite a few good visualization tools to show the logs made by kippo. You can save them to a db, plot them nicely, etc.

Ironic that the IP may now suffer another DOS attack because of HN trying to access it after reading the article.

I anonymized the IP addresses in a consistent way before publishing the blog post, so in the very worst case the DoS attack will go towards a completely new host :)