When requiring certificates for mobile devices, which authentication method is an option?

The option referencing SecureID (or SecurID) is a well-known method for two-factor authentication, which combines something the user knows (like a username and password) with something the user has (a physical token that generates a code). This approach enhances security by adding an additional layer of verification, making it particularly beneficial for mobile device authentication. As mobile environments are often seen as vulnerable due to various threats, using SecureID helps in safeguarding sensitive data accessed via these devices.

In scenarios involving mobile devices, employing certificate-based authentication can streamline the user experience while ensuring that only authorized devices access corporate resources. SecureID aligns well with this need, as it can be integrated into systems that require strong authentication mechanisms, including those utilizing device certificates.

The other options presented do not fit the context of mobile device authentication in the same manner. Complexity typically refers to password guidelines and doesn't involve certificate use. Tacacs (Terminal Access Controller Access-Control System) is more of a protocol for network device administration and user access control rather than an authentication method specifically applicable to mobile devices in relation to certificate requirements.