Anti tamper real time clock (RTC) – make your embedded system secure

The implementation of security features in embedded applications like utility metering, power distribution etc is becoming increasingly important. Lot of hacks around this area are related to tampering the time. While most of the anti-hacking techniques known can be handled in software, it is always secure and accurate to implement necessary ones in hardware. It is also efficient and cheaper to implement these techniques in System on Chip(SoC) than adding additional necessary logic on board that may open up more security holes. These hardware techniques need to be active at all times and must be monitored in all conditions. Since the Real Time Clock or RTC is a module that functions independently (both in terms of power supply and system clocks) with respect to rest of the blocks in a SoC, it inherently becomes the choice to implement the anti tamper functions. This article describes some of the techniques that can be well handled by RTC within a SoC by providing efficient protection against hardware as well as software tampers, thereby making it an essential item in every secure system. A small yet powerful block.