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Tech Note: Understanding Cyclic Redundancy Check
Published On: March 1, 1999

This technical note describes Cyclic Redundancy Check (CRC) in detail and shows an implementation of CRC within 4th Dimension.

CRC has been an integral part of the computer industry for quite some time. The actual implementation of CRC is quite simple, especially from within 4th Dimension. However, the concept behind CRC is less straightforward. CRC is rarely explained in a manner that is less than daunting. The aim of this technical note is to present the theory of CRC from the ground up, and enable the reader to understand CRC, without having a background in computer science. It explains how CRCs work and presents 4D code that makes CRCs easy to use in your applications.

The theory and implementation of CRC spans several “computer science” related topics. Each topic is addressed in a section of this technical note; each section within this technical note builds on the prior sections. Until you feel comfortable with your level of understanding of each section, I encourage you not to advance to the next section.

Tech Note