#sample of the custom asserter that uses third-party Perl modules for checking

#this asserter checks whether some host is online and if it is, it thinks
#that computer is connected to the internet
use IO::Socket;
my $host = "192.168.0.1";#www.google.com
my $remote = IO::Socket::INET->new(Proto=>"tcp", PeerPort=>80, PeerAddr=>$host);
if (!$remote) 
{ 
    print STDERR "It's illegal to use this script on computers without" .
	" direct connection to the Internet. Termination forced..\n";
    exit 0;
}
close $remote;
