The Design and Implementation of Online-Update on Embedded Devices

As more and more embedded network devices appear, in order to meet changes of the function requirement or to fix bugs of software, these devices need to be online-updated at any moment. However, the online-update which updates the applications or the kernel of the embedded devices should be completed in the bootloader for safety considerations. Restricted by the storage capacity, the embedded device can not realize the NIC driver and the protocol stack in the bootloader like mode based on Linux OS kernel. The paper presents an optimized solution, which includes NIC driver model, a special network protocol stack model and expands the bootloader with the NIC driver and the protocol stack. And then a complete implementation of the online-update is given.