The alternative: software-based protection

While dongles evolved as a form of physical protection, a parallel development has taken place. Digital protection technology has evolved in various forms.

Because of its reliance on software innovation rather than physical protection, the approaches to digital copy protection have evolved at a faster pace than dongle based systems.

Wrappers

Evolving from the loader-based mechanisms found in some software protection systems, software wrappers are envelopes of code that encrypt your own application binary. Because the software wrapper has to decrypt the code before it can be run, it can be programmed to check for the existence of a software license before allowing access.

SDK's

An SDK is a piece of copy protection code that has been developed for a specific application environment. Unlike wrappers, which are designed to fit around your existing code like a shell, SDK's integrate more tightly with your application. You can make calls to the application programming interface (API) presented by the software development kit from within your own software.

For example, whenever a particular function is called, it checks the details of your license using the SDK. In this way, it becomes more difficult for hackers to disassociate the copy protection from the application code. SDK's are stronger and harder to hack than wrappers and much cheaper and more flexible than dongles. They have more features and integrate with applications much more tightly, allowing for features such as custom screens, for example.

For more useful information, See "Software-based protection problems"