Philosophy of the Internet, part I:

  • Watching servers from outside and inside: open ports, services and client programs. What is a shell access? SSH an Telnet programs.

  • Other users on our machine and how to communicate with them online:

    Commands: w, who, finger, write, talk

  • IRC (Internet Relay Chat): an old, now elite internet text communicator.
  • How does e-mail work and what client programs there are

    • Web interface e-mail programs

    • E-mail clients using POP/IMAP and SMTP protocols. What is an smtp authentication anti-spam policy?

    • Analysis of e-mail headers. How to determine:

      • an internet provider (commands: nslookup, host, whois)

      • e-mail client

      • operating system

      • was the client computer behind a router/firewall (stealing the Internet? ­čÖé

      • spam level

    • How an anti-spam (SpamAssassin) program works and how to set it up for your account. Creating an imap SPAM folder.

    • Text console e-mail programs requiring a shell access from mail to pine.

    • Direct connection to an smtp port using Telnet: fake mails

      • General idea, more details
      • TRUST AND RELAY CONTROL section in /etc/postfix/main.cf (mynetworks, smtpd_recipient_restrictions)
      • SMTP authentication (put the appropriate valueas for username and password)
echo -en "username\x00username\x00password" | base64 
(read the man page for echo to find the -en options and the \x00 backslash sequence)

copy the result and paste it in telnet session after auth plain command. For example:

auth plain dXNlcm5hbWUAdXNlcm5hbWUAcGFzc3dvcmQ=
  • NETCAT (nc) – the „Swiss Army Knife” of the Internet – and its applications (sending handcrafted e-mail with an attachment, any process server)
  • FTP: web browsers, Total Commander, Dolphin, the text client

  • Secure FTP –> SFTP clients using ssh protocol on port 22

Philosophy of the Internet, part II:

  • Synchronizing your data on the Internet:

    • Cloud computing: Dropbox registration and use

    • Data synchronization special tool: rsync. Installing and running under Linux and Windows

rsync -auv  -e ssh --delete  /home/pgiza/documents pgiza@bacon.umcs.lublin.pl:/home/pgiza/
rsync -auv  -e ssh --delete  pgiza@bacon.umcs.lublin.pl:/home/pgiza/documents /home/pgiza/

Installing and running cwRsync under Windows

  • Internet communicators their advantages and drawbacks

    • Jabber

    • Skype

    • Jitsi (java)

    • Google+ Hangouts

    • Pidgin

  • File Sharing servers, networks and clients in legal use

  • The phenomenon of free, open-source software which resulted from interactive work of numerous, geographically dispersed programmers.Most famous projects developed under the GPL

  • What You or me will invent and consider worth talking about:)