Key exchange with the help of a public ledger

Blockchains and other public ledger structures promise a new way to create globally consistent event logs and other records. We make use of this consistency property to detect and prevent man-in-the-middle attacks in a key exchange such as Diffie-Hellman or ECDH. Essentially, the MitM attack creates an inconsistency in the world views of the two honest parties, and they can detect it with the help of the ledger. Thus, there is no need for prior knowledge or trusted third parties apart from the distributed ledger. To prevent impersonation attacks, we require user interaction. It appears that, in some applications, the required user interaction is reduced in comparison to other user-assisted key-exchange protocols

Towards Privacy-preserving network monitoring: issues and challenges

Passive network monitoring is required for the operation and maintenance of communication networks as well as to detect frauds and attacks. Typically, raw packet-level traffic traces are collected using suitable traffic probe devices and fed to monitoring applications (IDSs, antivirus, etc.) for analysis, with potential risks for the legitimate privacy rights of the customers. This paper aims to discuss the technical feasibility and the underlying research challenges of a two-tiered privacy-preserving network monitoring system, where carefully designed data protection mechanisms can coexist with suitably adapted monitoring applications