What Dr. Harris Taught

He discussed his own way to look at SMTP, POP and IMAP. i.e PQRST (Presentation-Queuing-Routing-Session-Transfer) model.

He described some of the RFCs for SMTP and POP3 and demonstrated its use using Telnet.
What I Learned

I read the PQRST model. I also setup a mail server to make my own domain and email account. I was able to send mails to my yahoo and google account and was able to see the tcpdump.