安全遠程更新擴展嵌入式系統功能和壽命

　　嵌入式系統是許多工業應用的核心，要求產品壽命長，同時響應功能更新和bug修復。安全問題，特別是，可以驅動要求頻繁的代碼更新，以保持領先的黑客和惡意入侵者。包括一個遠程更新設施，如果它可以得到擔保，可以極大地延長任何嵌入式系統的可用壽命。

　　本文將探討各種各樣的遠程系統更新中使用的現代嵌入式系統，通過顯示幾個不同的要求和方法。未來更敏感的嵌入式系統的要求也將討論最近的創新在MCU的功能，可以確定未來的增強方向。

　　Secure embedded system updates

　　Embedded systems are often connected to a network to transfer information from “edge” devices to central controllers. Central controllers are， in turn， connected to storage units， gateways， and traffic aggregation units all using a network connection. In order to simplify the installation of code updates and bug fixes the interconnect network is also used to download updates to programmable devices. These updates can simply be new parameters to adapt to environmental changes or they can be complete code “replacements” providing new features and capabilities.

　　Updates need to be done in a secure manner or attackers could hijack the update process， replacing reliable code with their own programs. Often these attacks leave start-up code that executes prior to future updates so that the inserted code can persist even after an attempt to update the “infected” system. Several approaches are used to protect remote updates and they vary in complexity depending on the value of the system as a target to a hacker. Clearly， systems that handle financial data are obviously in need of protection， but even a system you might not think of as being vulnerable may require increased security. Often it’s the element on the periphery of a more complex system that provides attackers with an easy in-road. For example， an intelligent thermostat or building control system might allow attackers an easy way into a data aggregation sub-system and then into the central controller of a financial institution.