Surveys reveal that network outages are prevalent, and that many outages take hours to resolve, resulting in significant lost revenue. Many bugs are caused by errors in configuration files which are programmed using arcane, low-level languages, akin to machine code. Further, mistakes are often hunted down using rudimentary tools such as Ping and Traceroute.
Taking our cue from other fields such as hardware design, we suggest fresh approaches. Our first attempt was a geometric model of network forwarding called Header Space together with parsers that convert router configurations to header space representations. Header Space ideas were used to build a static checker (Hassel) that can identify reachability bugs and a dynamic checker (ATPG) that can identify performance faults. Unlike classical model checkers, Hassel does not have a notion of a specification language or a modeling language, which makes it difficult to write higher level specifications or deal with changing router behaviors. Our attempt to remedy this was to teach an old dog (Datalog) new tricks to create what we call Network Optimized Datalog (NoD) followed by extensions to quantitative and automatic verification.
These results suggest that concepts from Electronic Design Automation (EDA) and program verification can be leveraged to create what might be termed Network Design Automation (NDA). What might the equivalent of Layout Versus Schematic tools or Specification Mining be? What are the differences in the domain that can be exploited? The second part of this talk will explore this vision, touching upon modular network semantics, language design, performance invariants, and interactive network debuggers. This is joint work with collaborators at Berkeley, MSR, and Stanford.
George Varghese received his Ph.D. in 1992 from MIT. From 1993-1999, he was a professor at Washington University, and at UCSD from 1999 to 2013. He was the Distinguished Visitor in the computer science department at Stanford University from 2010-2011. He joined Microsoft Research in 2012.
His book "Network Algorithmics" was published in December 2004 by Morgan-Kaufman. In May 2004, he co-founded NetSift, which was acquired by Cisco Systems in 2005. With colleagues, he has won best paper awards at SIGCOMM (2014), ANCS (2013), OSDI (2008), PODC (1996), and the IETF Applied Networking Prize (2013). He won the Kobayashi Award and the SIGCOMM Lifetime Award, both in 2014, and the IIT Bombay Distinguished Alumni Award in 2015.