Software updates are crucial on every platform to keep products competitive, secure and performing optimally.
By applying Logiblock's embedded gzip decompressor, firmware updates can be sent using the minimum of space, time and bandwidth. Moreover, our gzip decoder can also be used to expand delta-updates that contain only the changes between one version and another without any dedicated differential-patching decoder. This yields the highest compression-ratio-per-decoder-size relationship, which is a crucial factor for deeply-embedded systems where firmware size of the codec itself is a significant aspect of total compression efficiency.
Lockitron needed the ability to re-program one of its application processors, an AVR chip, from an Electric Imp Wifi module on-board. Additionally, the mechanism had to be secure against tampering or bus-probing. A cryptographic bootloader was developed for the AVR using the AES block cipher that could program the application firmware and contained multiple failsafes to allow recovery from any failure mode.
[A home-automation product] needed efficient over-the-air firmware updates over a very-low-bandwidth, unreliable BLE channel. Furthermore, firmware downloads had to occur without inconveniencing the user because communication would only occur in proximity to the device and a full download could take several weeks. A self-healing communications scheme was designed, simulated and applied that was robust against communication loss yet would guarantee the integrity of the payload. Due to code size constraints the new firmware had to be stored compressed and could not be executed directly, so a high-reliability unified verification, decompression and self-programming step was used to complete the update.
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