Beginning PHP and MySQL: From Novice to Professional, Third Edition

CHAPTER 14Authenticating Your Users

Authenticating user identities is common practice in today's Web applications. This is done not only for security-related reasons, but also to offer site customization features based on user preferences and type. Typically, users are prompted for a username and password, the combination of which forms a unique identifying value for that user. In this chapter, you'll learn how to prompt for and validate this information, using PHP's built-in authentication capabilities. Specifically, in this chapter you'll learn about:

• Basic HTTP-based authentication concepts
• PHP's authentication variables, namely $_SERVER['PHP_AUTH_USER'] and $_SERVER['PHP_AUTH_PW']
• Several PHP functions that are commonly used to implement ...