# Disable response to ping:
        echo "0" > /proc/sys/net/ipv4/icmp_echo_ignore_all

        # Disable response to broadcasts:
        echo "1" > /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts

        # Enable TCP SYN cookies:
        echo "1" > /proc/sys/net/ipv4/tcp_syncookies

        # Enable bad error messages protection:
        echo "1" > /proc/sys/net/ipv4/icmp_ignore_bogus_error_responses

        # Disable IP forwarding:
        echo "0" > /proc/sys/net/ipv4/ip_forward

        echo "1" > /proc/sys/net/ipv4/tcp_rfc1337
        echo "0" > /proc/sys/net/ipv4/ip_no_pmtu_disc
        echo "1" > /proc/sys/net/ipv4/tcp_sack
        echo "1" > /proc/sys/net/ipv4/tcp_fack
        echo "1" > /proc/sys/net/ipv4/tcp_window_scaling
        echo "1" > /proc/sys/net/ipv4/tcp_timestamps
        echo "0" > /proc/sys/net/ipv4/tcp_ecn
        echo "1" > /proc/sys/net/ipv4/route/flush

        echo "1440000"  > /proc/sys/net/ipv4/tcp_max_tw_buckets
        echo "15"       > /proc/sys/net/ipv4/tcp_fin_timeout
        echo "1800"     > /proc/sys/net/ipv4/tcp_keepalive_time
        echo "1280"     > /proc/sys/net/ipv4/tcp_max_syn_backlog

        echo "4096 87380 16777216" > /proc/sys/net/ipv4/tcp_rmem
        echo "4096 65536 16777216" > /proc/sys/net/ipv4/tcp_wmem
        echo "16777216" > /proc/sys/net/core/rmem_max
        echo "16777216" > /proc/sys/net/core/rmem_default
        echo "16777216" > /proc/sys/net/core/wmem_max
        echo "16777216" > /proc/sys/net/core/wmem_default


        for interface in /proc/sys/net/ipv4/conf/*
        do
            echo "0" > ${interface}/send_redirects
            echo "0" > ${interface}/accept_redirects
            echo "1" > ${interface}/secure_redirects
            echo "0" > ${interface}/accept_source_route
            echo "0" > ${interface}/bootp_relay
            echo "0" > ${interface}/proxy_arp
            echo "1" > ${interface}/log_martians
            echo "1" > ${interface}/rp_filter
        done