LTE 裝置上之TR-069 韌體更新實作

Abstract

由於4G LTE網路大規模普及化，許多裝置已配備LTE網路之能力，在LTE裝置上隨著應用的多元化，運作在該裝置上的軟體程式就隨之愈複雜，雖然每個LTE產品在設計與生產階段都會投入龐大的人力物力對產品做檢驗以確保量產的產品有最佳的軟體品質，然而要讓軟體完全達到無軟體臭蟲（Bug）機乎是不太可能的任務，因為一個嵌入式系統所包含的程式碼多達數千萬個邏輯運算，若是嚴重的軟體臭蟲發生，廠商勢必花費許多人力物力來更改已經出廠的每一臺裝置上的韌體。

本研究之LTE裝置為一個基於Embedded Linux的LTE路由器，因為該裝置之作業系統並無內建遠端韌體更新機制，故為了有效解決產品出廠後的韌體更新議題，我們在一些基於OTA（Over the Air）的軟韌體更新機制裡挑選了較適合路由器配置的TR-069通訊協定來實作一個基於TR-069的遠端韌體更新機制，探討如何實作在LTE裝置上的OTA軟韌體更新功能、LTE與TR-069軟體如何做有效的串接和TR-069系統架構的設計，另外本研究藉著實驗設計來驗證此實作之穩定度，並在LTE-TDD網路進行TR-069之驗證，找出適合本研究之TR-069的LTE參數。

The LTE telecommunication network is widely constructed today, and billions of LTE devices be widely spread to end-users over the world. As the LTE use-case become more complex, the software which run on LTE devices are also being sophisticated. Although the software developers pay big attention to verify the quality of software to ensure that every devices are bundled with perfect embedded software. But we must to say that, it's impossible to get bug-free software because there are too many software logic components contained in an embedded system. Once a critical bug has been reported, the manufacturter have to pay heavy fee to fix it.

The target device of this paper is a LTE Router which run on an Embedded Linux, however, no remote firmware upgrade machanism was bundle with it. For resolving the firmware upgrade issue of this device, we choice TR-069 protocol which is design for network Router products to implement a remote firmware upgrade mechanism. Today, firmware upgrade through OTA（Over the Air） is more and more popular and applied on many consumer devices. In this paper, we discuss about how to implement remote firmware upgrade mechanism through TR-069 protocol on a LTE device. We discuss how TR-069 client can work with LTE network interface with Linux system events and the system architecture of development TR-069 client software. We evaluate this implementation on LTE-TDD network, examine the performances behavior and find suitable LTE parameters.