Professional Windows Server 1002003 Security A Technical Reference [Electronic resources] نسخه متنی

Chapter 2. Authentication: Proof of Identity

The most important thing that you can do to manage information access is to require that those who want to access information provide proof of identity. If you require all potential users of your information system resources to authenticate themselves, that is, to prove they are who they say they are, then you can restrict system and resource access to approved identities. Authentication can be a precursor to authorization and accountability. Authorization determines the type of access the authenticated users are allowed and the rights they have on the system. Accountability is the ability to determine who did what. It is based on your ability to record the systems and resources that users have accessed and the things they have done while connected to these resources. Requiring authentication facilitates both authorization and accountability. However, if you know nothing about processing credentials and verifying identities, and if you do not harden and manage these processes, you can support neither authorization nor accountability. You may as well have required no proof of identity at all. The content in this chapter will provide the knowledge and best practices you need to successfully harden authentication.

The process of authentication is familiar to most people. In the real world, we are often required to authenticate ourselves. We present a driver's license before we can board a plane, a passport before we can enter a different country, or a company ID to enter business offices. These documents are validated, in many cases, by the simple process of comparing the picture on the document with the person presenting it, and comparing the features of the credentials (official stamps, seals, and signatures) with those we know to be valid. In legacy versions of the Windows operation system, authentication is optional. However, authentication is required to access Windows systems based on Windows NT technologies (Windows NT 4.0, Windows 2000, Windows XP Professional, and Windows Server 2003). Authentication occurs when each user logs on, and again when that user attempts to access resources such as files, remote computers, printers, and so forth. The credentials required consist of a valid account and some factor such as password, biometric, token, or certificate. The process used to authenticate the user will vary depending on the specific authentication algorithm used and how it is configured. An important part of authentication management is knowing what's possible, what's practical, and what's allowed and then knowing how to use that information to make your systems as secure as they can be.

TIP: Monitor Security Logs During Times of Normality

Failed logons and other authentication anomalies may be user errors, improper system configurations, or network problems, or they may be indications of an attack. If you monitor the authentication process and learn to determine the cause of errors, you will be able to better respondwhatever the real cause.