Location
New Computer Science, Room 220
Event Description

Hyperscale Verification in Microsoft Azure talk by Nikolaj Bjorner

Abstract: Cloud providers are increasingly embracing network verification for managing complex datacenter network infrastructure. Microsoft's Azure cloud infrastructure integrates the SecGuru tool, which leverages the Z3 Satisfiability Modulo Theories solver, for checking network access
control lists. It also integrates a verifier that uses both custom verification algorithms and Z3 that checks correctness of forwarding tables in Azure data-centers. These tools assure that the network is configured to preserve desired intent over hundreds of thousands of network devices. We describe our experiences building and running SecGuru for network verification in Azure.

Finally we mention recent advances in Z3, including a distributed version of Z3 that scales with Azure's elastic cloud. It integrates recent advances in lookahead and distributed SAT solving for Z3's
engines for SMT. A different recent advance includes integration of DNNs to learn variable branching strategies for high-performance SAT solvers, including MiniSAT, Glucose and Z3’s SAT solver.

Bio: Nikolaj Bjorner is a Principal Researcher at Microsoft Research, Redmond, working in the area of Automated Theorem Proving and Software Engineering. His current main line of work is around the state-of-the art theorem prover Z3, which is used as a foundation of several software engineering tools. Z3 received the 2015 ACM SIGPLAN Software System award and most influential tool paper in the first 20 years of TACAS in 2014, and test of time award at ETAPS 2018. Together with Leonardo de Moura received the CADE 2019 Herbrand award for contributions to SMT and applications. Previously, he developed the DFSR, Distributed File System - Replication, and Remote Differential
Compression protocols, RDC, part of Windows Server since 2005 and before that worked on distributed file sharing systems at a startup, and program synthesis and transformation systems at the Kestrel Institute. He received his Master’s and PhD degrees in computer science from Stanford University.

Event Title
Hyperscale Verification in Microsoft Azure presented by Nikolaj Bjorner