I am new to implementing information security. However i am trying to harden a windows server.I am using regedit to create parameters like SynAttackProtect,TcpMaxHalfOpen and TcpMaxHalfOpenRetried and set values to them. But i am not sure if this is a good way to do it. As in i browsed to this location HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\TcpIp\Parameters and manually adding these parameters. Kindly suggest if this is okay
Completely preventing TCP SYN flood attacks is impossible; the best you can do is to mitigate them. Those registry settings are a valid option and may help you if you are under a weak or mild SYN flood attack. They work by simply limiting the duration and amount of half open connections when undergoing the symptoms of a SYN flood. In other words it makes the server less patient in waiting for the client to complete the three-way handshake (i.e. completing the connection).
Here are a few other common defenses to help mitigate SYN flood attacks:
For additional reading on these SYN flood mitigation methods, I suggest reading section 3 of RFC 4987
Hope this helps!