DATE: Thursday, February 5, 2009
TIME: 12:00 pm - 1:00 pm
PLACE: Wean Hall 8220

Jon Howell
Microsoft Research

Xax: Leveraging Legacy Code to Deploy Desktop Applications on the Web

Xax is a browser plugin model that enables developers to leverage existing tools, libraries, and entire programs to deliver feature-rich applications on the web. Xax employs a novel combination of mechanisms that collectively provide security, OS-independence, performance, and support for legacy code. These mechanisms include memory-isolated native code execution behind a narrow syscall interface, an abstraction layer that provides a consistent binary interface across operating systems, system services via hooks to existing browser mechanisms, and lightweight modifications to existing tool chains and code bases. We demonstrate a variety of applications and libraries from existing code bases, in several languages, produced with various tool chains, running in multiple browsers on multiple operating systems. With roughly two person-weeks of effort, we ported 3.3 million lines of code to Xax, including a PDF viewer, a Python interpreter, a speech synthesizer, and an OpenGL pipeline.


Jon works at the intersection of security and scalability in distributed systems. His recent projects focus on the convergence of utility computing and web-delivered applications. He has worked on the novel Asirra Captcha, a rigorous proof of correctness for Paxos, the Farsite distributed filesystem, and cross-domain authentication.

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