What is ActiveX?
ActiveX was launched by Microsoft in 1996. It was created as an expansion of their Component Object Model (COM) and Object Linking and Embedding (OLE) technologies. ActiveX is a model used to define reusable controls or software components that carry out a specific function or set of functions in the Microsoft Windows operating system. ActiveX controls operate independently of the programming language utilized to employ them. A software program can be created from one or more ActiveX controls to provide functionality. ActiveX is often used for increased website functionality.
ActiveX is (was) an outgrowth of two other Microsoft technologies, object linking and embedding and the component object model. ActiveX controls refer to a specific way of implementing those technologies. A limitation of the ActiveX control is that it can only run under Windows. ActiveX controls can also expose a system to viruses and malware because they create an opening that can allow these malicious programs to be installed. While technically still around technology is no longer commonly used in modern web development.
History of ActiveX
ActiveX was first introduced by Microsoft in the early 1990s as a way to extend the capabilities of its Windows operating system. It was initially designed to allow the creation of reusable software components, called controls, that could be used by developers to build custom applications. Over time, ActiveX evolved to become a more general-purpose technology that could be used to create interactive content for the web. This was made possible by the introduction of ActiveX controls that could be embedded into web pages to provide rich multimedia experiences.
Faced with the complexity of OLE 2.0 and with poor support for COM in MFC, Microsoft simplified the specification and rebranded the technology as ActiveX in 1996. Even after simplification, users still required controls to implement about six core interfaces. In response to this complexity, Microsoft produced wizards, ATL base classes, macros, and C++ language extensions to make it simpler to write controls. Starting with Internet Explorer 3.0 (1996), Microsoft added support to host ActiveX controls within HTML content. If the browser encountered a page specifying an ActiveX control via an OBJECT tag, it would automatically download and install the control with little or no user intervention. This made the web "richer" but provoked objections (since such controls, in practice, ran only on Windows, and separate controls were required for each supported platform: one for Windows 3.1/Windows NT 3.51, one for Windows NT/95, and one for Macintosh F68K/PowerPC.) and security risks (especially given the lack of user intervention). Microsoft subsequently introduced security measures to make browsing including ActiveX safer. For example:
- digital signing of installation packages (Cabinet files and executables)
- controls must explicitly declare themselves safe for scripting
- increasingly stringent default security settings
- Internet Explorer maintains a blacklist of bad controls
ActiveX was controversial from the start; while Microsoft claimed programming ease and good performance compared to Java applets in its marketing materials, critics of ActiveX were quick to point out security issues and lack of portability, making it impractical for use outside protected intranets. The ActiveX security model relied almost entirely on identifying trusted component developers using a code-signing technology called Authenticode. Developers had to register with Verisign (US$20 per year for individuals, $400 for corporations) and sign a contract, promising not to develop malware. Identified code would then run inside the web browser with full permissions, meaning that any bug in the code was a potential security issue; this contrasts with the sandboxing already used in Java at the time.
Features of ActiveX
ActiveX provides a rich set of features that enable the creation of interactive applications for the Windows platform. Some of the key features of ActiveX include:
- Reusability: ActiveX controls can be easily reused in multiple applications, reducing the development time and cost.
- Interoperability: ActiveX controls can be used across different programming languages and platforms, making it easy to integrate them into existing applications.
- Security: ActiveX controls can be digitally signed, ensuring that they come from a trusted source and have not been tampered with.
- Rich multimedia: ActiveX controls can provide rich multimedia experiences, including video and audio playback, animation, and interactive 3D graphics.
Architecture of ActiveX
The architecture of ActiveX is a complex and multifaceted system that includes various components and technologies. At a high level, ActiveX is based on the Component Object Model (COM), which is a binary interface standard developed by Microsoft. COM defines a standard set of rules for how software components can interact with each other, allowing components to be developed and reused across different applications and programming languages.
ActiveX builds on top of COM by adding additional functionality for creating and embedding interactive content in web pages and other applications. The main components of the ActiveX architecture include:
- ActiveX controls: ActiveX controls are reusable software components that can be embedded in web pages or other applications to provide interactive functionality. These controls can be developed using a variety of programming languages, including C++, Visual Basic, and Java.
- ActiveX container: An ActiveX container is an application that hosts ActiveX controls. Containers provide a framework for managing controls and *ActiveX scripting: ActiveX scripting allows developers to add scripting support to ActiveX controls. This enables controls to be programmed using scripting languages such as VBScript and JScript, which can be executed directly in the browser.
- ActiveX Data Objects (ADO): ADO is a set of components and interfaces that allow applications to access and manipulate data stored in databases. ADO can be used to create data-driven ActiveX controls that interact with databases to display and update data.
- ActiveX Document Objects (ADO): ADO is a set of components and interfaces that allow developers to create documents that can be viewed and edited using ActiveX controls. This includes technologies such as Microsoft Office and Internet Explorer.
ActiveX controls and their development
ActiveX controls are a type of software component that can be embedded in web pages or other applications to provide interactive functionality. ActiveX controls are developed using a variety of programming languages, including C++, Visual Basic, and Java, and are designed to be reusable across multiple applications.
The development process for ActiveX controls typically involves the following steps:
- Design: The first step in developing an ActiveX control is to define its functionality and user interface. This involves creating a set of specifications or requirements that describe what the control should do and how it should look.
- Coding: Once the design is complete, the actual coding of the control can begin. This involves writing the source code for the control using the chosen programming language.
- Testing: After the control has been coded, it must be tested to ensure that it works as expected. This involves testing for functionality, performance, and security vulnerabilities.
- Deployment: Once the control has been tested and verified, it can be deployed to users. This involves creating a binary file that contains the compiled code for the control, along with any other necessary resources such as images or configuration files.
The tools used to develop ActiveX controls vary depending on the programming language being used. For example, if the control is being developed using Visual Basic, the developer might use the Microsoft Visual Basic development environment to write and test the code. If the control is being developed using C++, the developer might use a tool such as Microsoft Visual Studio.
In terms of best practices for creating secure, reliable ActiveX controls, there are several key considerations. These include:
- Digital signing: ActiveX controls should be digitally signed to ensure that they come from a trusted source and have not been tampered with.
- Sandboxing: ActiveX controls should be run in a sandboxed environment that limits their access to system resources and prevents them from making unauthorized changes.
- Least privilege: ActiveX controls should be designed to run with the least possible privileges, only accessing the resources and data that they actually need.
- Compatibility: ActiveX controls should be designed to be compatible with as many different versions of Windows and web browsers as possible, to ensure maximum compatibility with end-user systems.
- Documentation: ActiveX controls should be thoroughly documented to make it easier for other developers to understand their functionality and usage.
By following these best practices, developers can create secure, reliable ActiveX controls that can be used across a wide range of applications and platforms.
Impact of ActiveX on Web Development
ActiveX had a significant impact on web development in the 1990s and early 2000s. It enabled developers to create rich, interactive content for the web, including games, animations, and other multimedia experiences.
While ActiveX was once a popular technology for creating interactive content on the web, it has become less relevant in modern web development.
One of the biggest limitations of ActiveX is its interoperability and lack of cross-platform compatibility. Because ActiveX is a proprietary technology developed by Microsoft, it is only compatible with the Windows platform. This limits its usefulness in cross-platform applications and makes it less relevant in today's increasingly diverse computing landscape.
Another limitation of ActiveX is its potential security risks. ActiveX controls can be used to download and execute arbitrary code, which can be exploited by attackers to install malware, steal sensitive information, or compromise the integrity of a system. This has led to numerous security vulnerabilities and exploits over the years, making ActiveX a less secure choice for creating interactive web content.
That being said, there are still some cases where ActiveX may be used in modern web development, particularly in legacy applications that were developed before the emergence of newer web technologies. In these cases, developers may need to continue using ActiveX to maintain compatibility with existing applications and systems.
Alternatives to ActiveX
As ActiveX has become less relevant in modern web development, developers have turned to a variety of alternative technologies and approaches to build interactive web content beyond ActiveX. While some of these alternatives may be proprietary or limited to certain platforms, many are open standards that are widely supported and more secure than ActiveX. Developers should carefully consider the needs of their applications and the limitations of each technology before choosing the best approach for creating interactive web content. Some of the most popular alternatives to ActiveX include:
- Adobe Flash: Flash is a multimedia platform developed by Adobe that can be used to create interactive content such as animations, games, and videos. While Flash was once a dominant technology for creating interactive web content, it has become less popular in recent years due to security concerns and the emergence of newer web technologies such as HTML5.
- Silverlight: Silverlight is a plugin developed by Microsoft that can be used to create rich, interactive content for the web. Like ActiveX, Silverlight is a proprietary technology that is limited to the Windows platform, but it provides more advanced features than ActiveX and is less prone to security vulnerabilities.
- HTML5: HTML5 is the latest version of the HTML standard, which provides a wide range of features and functionality for creating interactive web content. HTML5 includes support for video and audio playback, animation, and 3D graphics, making it a popular choice for modern web development. Unlike ActiveX, HTML5 is an open standard that is platform-independent and more secure.