Allow following ports for global access.
# Allow following port for global access
-A INPUT -p tcp -m state --state NEW -m tcp --dport 80 -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 19999 -j ACCEPT
# Allow following port for selected access
-A INPUT -s {IP_ADDRESS_1}/24 -j ACCEPT
-A INPUT -s {IP_ADDRESS_2}/24 -j ACCEPT
-A INPUT -s {IP_ADDRESS_3}/24 -j ACCEPT
-A INPUT -s {IP_ADDRESS_4}/24 -j ACCEPT
sudo service iptable restart
sudo iptables -S