A blockchain consists of a list of blocks that are linked based on cryptography hash and maintained by distributed network nodes, so that the information recorded in these blocks is non-repudiated. After its first conceptualization by Nakamoto in 2008, blockchain has attracted broad attention and been considered as a promising solution to establish a decentralized architecture with security. In this talk, we will discuss some key characteristics of blockchain and a few promising applications of blockchain that can facilitate security and trust among multiple parties. Some examples include applying blockchain to secure software updates for resource-constrained IoT networks; designing a secure and efficient multi-signature scheme to facilitate multi-party approval process on Fabric, an enterprise blockchain platform; and facilitating fair trading of digital-goods via a blockchain based proxy re-encryption scheme. Speaker(s): Yuhong Liu, Virtual: https://events.vtools.ieee.org/m/328082