Edge computing has quickly risen as an effective paradigm to capture, process, gain insights from, and act upon the massive amount of Internet of Things (IoT) data close to where it is generated. Future edge computing systems are expected to be hierarchical and heterogeneous. It will become increasingly common for a single IoT application to utilize edge computing resources owned by multiple entities. This project envisions the emergence of hierarchical edge computing (HEC) service providers that purchase computing services from heterogeneous multi-owner edge computing systems and provide unified edge computing services to individual IoT applications. The development of HEC systems will have a profound impact on transportation, healthcare, energy, education, social life, public safety, and many other sectors. Security and privacy are among the most challenging obstacles that hinder the wide development and deployment of the promising HEC paradigm. This project aims to tackle key security and privacy challenges in HEC systems, under which heterogeneous multi-owner edge computing systems can jointly provide trustworthy computing services to end-users via a single service provider. There are four research thrusts: (1) developing novel techniques to authenticate data streams with freshness guarantees; (2) investigating locally differentially private data analysis techniques via correlated randomized responses; (3) designing a novel framework for distributed privacy-preserving collaborative learning; and (4) building a prototype HEC system to thoroughly validate and evaluate the proposed techniques. If successful, the research can serve as a key enabler for the explosive development and deployment of edge computing services and IoT applications. The research will also enrich the scientific knowledge of network and distributed system security, data privacy, and edge computing. A substantial quantity of project deliverables will be made publicly available online through tutorials, talks, publications, and software toolkits. In addition, this project will integrate the research activities with curriculum development, provide research opportunities to female and underrepresented students, enhance undergraduate research experience through senior design projects, and foster the interest of K-12 students in science, technology, engineering, and math (STEM) via outreach programs.