Network Access

• Don't assume that you can reach the public Internet.
• Don't assume that you can reach outside world through any other port than 80, or some web proxy. ftp is blocked by many firewalls.
• Don't assume that you can send email by connecting to the local SMTP port.
• Don't assume that you can ping hosts and get replies.
• Don't assume that any particular port (service) will respond.
• Perl Monks Article - http://www.perlmonks.org/index.pl?node_id=349910
  • "Phone Home" distributions