


Briefly describe the development history of PHP technology_PHP tutorial
Everyone is familiar with PHP technology. Let’s review the development history of PHP technology. The last decade of the last century was the most important decade for Web applications from their birth to maturity. In 1990, the world's first Web server was born, and in 1991, the world's first Web browser was born. In the following years, due to the improvement of computer hardware levels, the scale of Web applications also gradually expanded. During this period, many web development languages were also born, among which PHP is a more outstanding web development language. Does the birth of PHP mean that Web applications will move into a new era? Can it withstand the attack of other Web development languages?
PHP technology turns out
In 1994, Rasmus Lerdorf first designed the PHP programming language. In June 1995, Rasmus Lerdorf published the PHP 1.0 announcement on the Usenet news group comp.infosystems.www.authoring.cgi. In this early version, simple functions such as guest book and visitor counter were provided. In mid-1995, the second version of PHP was launched on the market, named PHP/FI (Form Interpreter). In this version, a parser that can handle more complex embedded tag languages has been added. Since then, PHP's influence in dynamic web development has been established.
Since PHP added these powerful features, its usage has skyrocketed. According to preliminary statistics, at the end of 1996, 15,000 Web sites used PHP/FI; and in mid-1997, this number exceeded 50,000.
PHP has evolved through three versions and has become a very powerful web development language. This language is very easy to use, and it has a powerful class library, and the naming rules of the class library are also very standardized. Even if you don't understand the functions of some functions, you can guess them through the function names. This makes PHP very easy to learn, and PHP programs can be processed directly using an HTML editor. Therefore, PHP has become very popular after 1998. Many large portals (such as Sina) use PHP as their Web Development language.
PHP technology faces pressure and moves forward bravely
There will never be the only choice in this diverse world. In the following years after the birth of PHP, Web applications were gradually recognized by the majority of users. During this period, some web development languages similar to PHP were also born, the most famous of which are ASP and JSP (ASP and JSP are different from PHP. They are not languages themselves, but a web development technology. ASP can Use JScript or VBScript for development, while JSP can only be developed using Java). ASP was born in 1996, the second year after former Microsoft CEO Bill Gates announced that all Microsoft products would be equipped with Internet capabilities. Although ASP can only run on the Windows platform, due to Microsoft's strong support and the simplicity and ease of use of ASP, this technology has gradually attracted a large number of users from PHP. JSP, which was born in 1998, has strong momentum. Since JSP has almost the same advantages as PHP, and JSP runs on the JVM, its efficiency is theoretically higher than that of PHP. With the birth of these two technologies, PHP is being attacked from both sides.
However, PHP was not to be outdone. After continuous improvement, it finally launched an epoch-making version, PHP4, in May 2000. This version uses the Zend (Zeev + Andi) engine, provides higher performance, and also includes other key features, such as: support for more web servers; HTTP Sessions support; output buffering; more security methods for handling user input and some new language constructs.
The competition of web development languages has also undergone considerable changes since the 21st century. Although ASP won some users at the beginning, because the development languages of ASP are JScript and VBScript, it lacks a class library as powerful as PHP and JSP. Although ASP can make up for this shortcoming by calling COM components, this will It's very troublesome. Although JSP has a powerful class library and can be cross-platform, because the Java language is a strongly typed language, and the tags and other specifications defined by JSP are too complex, this makes JSP more complicated to use than PHP. Therefore, PHP was slightly at the top of the Web competition in the last century. But as the 21st century progresses, the situation becomes more complicated.

Effective methods to prevent session fixed attacks include: 1. Regenerate the session ID after the user logs in; 2. Use a secure session ID generation algorithm; 3. Implement the session timeout mechanism; 4. Encrypt session data using HTTPS. These measures can ensure that the application is indestructible when facing session fixed attacks.

Implementing session-free authentication can be achieved by using JSONWebTokens (JWT), a token-based authentication system where all necessary information is stored in the token without server-side session storage. 1) Use JWT to generate and verify tokens, 2) Ensure that HTTPS is used to prevent tokens from being intercepted, 3) Securely store tokens on the client side, 4) Verify tokens on the server side to prevent tampering, 5) Implement token revocation mechanisms, such as using short-term access tokens and long-term refresh tokens.

The security risks of PHP sessions mainly include session hijacking, session fixation, session prediction and session poisoning. 1. Session hijacking can be prevented by using HTTPS and protecting cookies. 2. Session fixation can be avoided by regenerating the session ID before the user logs in. 3. Session prediction needs to ensure the randomness and unpredictability of session IDs. 4. Session poisoning can be prevented by verifying and filtering session data.

To destroy a PHP session, you need to start the session first, then clear the data and destroy the session file. 1. Use session_start() to start the session. 2. Use session_unset() to clear the session data. 3. Finally, use session_destroy() to destroy the session file to ensure data security and resource release.

How to change the default session saving path of PHP? It can be achieved through the following steps: use session_save_path('/var/www/sessions');session_start(); in PHP scripts to set the session saving path. Set session.save_path="/var/www/sessions" in the php.ini file to change the session saving path globally. Use Memcached or Redis to store session data, such as ini_set('session.save_handler','memcached'); ini_set(

TomodifydatainaPHPsession,startthesessionwithsession_start(),thenuse$_SESSIONtoset,modify,orremovevariables.1)Startthesession.2)Setormodifysessionvariablesusing$_SESSION.3)Removevariableswithunset().4)Clearallvariableswithsession_unset().5)Destroythe

Arrays can be stored in PHP sessions. 1. Start the session and use session_start(). 2. Create an array and store it in $_SESSION. 3. Retrieve the array through $_SESSION. 4. Optimize session data to improve performance.

PHP session garbage collection is triggered through a probability mechanism to clean up expired session data. 1) Set the trigger probability and session life cycle in the configuration file; 2) You can use cron tasks to optimize high-load applications; 3) You need to balance the garbage collection frequency and performance to avoid data loss.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

SublimeText3 English version
Recommended: Win version, supports code prompts!

ZendStudio 13.5.1 Mac
Powerful PHP integrated development environment

Safe Exam Browser
Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.

SublimeText3 Chinese version
Chinese version, very easy to use

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function
