Far from serving only as a foundation for cryptocurrency, blockchain technology provides a general framework for trusted distributed ledgers. Over the past few years, their popularity has grown tremendously, as shown by the number of companies and efforts associated with the Linux Foundation’s Hyperledger project, for example. From a technical standpoint, a blockchain combines a storage layer, networking protocols, a consensus layer, and a programmable transaction layer, leveraging cryptographic operations. The distributed state machine paradigm provides atomicity and transaction rollback, while consensus supports distributed availability as well as certain forms of fair access. From an applications perspective, blockchains appeal to distributed networks of independent agents, as arise in supply chain, credentialing, and decentralized financial services. The talk will look at the potential for radical change as well as specific technical challenges associated with verifiable consensus protocols and trustworthy smart contracts.
Often network defenders fail to take into account organizational culture when attempting to provide a secure, reliable, and usable enterprise network. Users and process leaders often fall victim to the false allure of the value of networked systems, without asking the question, “Should this be networked?” Collectively, organizations also forget that networks are a combination of the humans who use the network, the personas we all have to form to gain access to this manmade domain, and the interplay of logical and physical network architecture manifested in geographical locations. The value of some simple military principles—including defense-in-depth, mission focus, redundancy, and resiliency versus efficiency—can help a network defender better advise everyone from the “C Suite” decision-makers to the average network user, on how to have a secure network while accepting reasonable limitations.