KERNEL PARAMETER CONFIGURATION:

# PREVENT YOU SYSTEM FROM ANSWERING ICMP ECHO REQUESTS

 echo 1 > /proc/sys/net/ipv4/icmp_echo_ignore_all

 # DROP ICMP ECHO-REQUEST MESSAGES SENT TO BROADCAST OR MULTICAST ADDRESSES

 echo 1 > /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts

 # DONT ACCEPT ICMP REDIRECT MESSAGES

 echo 0 > /proc/sys/net/ipv4/conf/all/accept_redirects

 # DONT SEND ICMP REDIRECT MESSAGES

 echo 0 > /proc/sys/net/ipv4/conf/all/send_redirects

 # DROP SOURCE ROUTED PACKETS

 echo 0 > /proc/sys/net/ipv4/conf/all/accept_source_route

 # ENABLE TCP SYN COOKIE PROTECTION FROM SYN FLOODS

 echo 1 > /proc/sys/net/ipv4/tcp_syncookies

 # ENABLE SOURCE ADDRESS SPOOFING PROTECTION

 echo 1 > /proc/sys/net/ipv4/conf/all/rp_filter

 # LOG PACKETS WITH IMPOSSIBLE ADDRESSES (DUE TO WRONG ROUTES) ON YOUR NETWORK

 echo 1 > /proc/sys/net/ipv4/conf/all/log_martians

 # DISABLE IPV4 FORWARDING

 echo 0 > /proc/sys/net/ipv4/ip_forward

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