for my $ip ( sort keys %host ) {
    print "$ip\n";
    for my $proto ( sort keys %{$host{$ip}} ) { # assuming there will be keys other than "tcp"
        for my $port ( sort {$a<=>$b} keys %{$host{$ip}{$proto}} ) {
            printf( "%3d\t%s\t%s\n", $port,
                    $host{$ip}{$proto}{$port}{state},
                    $host{$ip}{$proto}{$port}{service} );
        }
    }
}