My client has SSL VPN enabled on his ASA. THe client wants to prevent brute force attack to the SSL VPN. He is using ACS for user authentication with max failed login limited to 3 attempts. However, if the username is not in the database ACS won't block the brute force attempts.
Is there a way to prevent this type of attack so that the brute forcing IP is denied for a period of time? Would an IPS or AIP-SSM do the job? Any documents or links are appreciated.
Thanks in advamce,