Determine the computing infrastructure

One solution for the protection of the computing infrastructure is to use digital certificate-based solutions. Users can be given access based on their possession of certificates signed or authorised for access by or on behalf of the server to which they intend to have access. There are a number of certification solutions available in the market today. The certificate acts as evidence of the user's digital identity. Certificates can also be combined with other access control mechanisms, such as emails, money transactions, tokens (a form of identification hardware carried by users) or only accepting visitors from certain controlled group or authenticated addresses.