Advanced Operating Systems - Spring 2009 Lecture 24 – Wednesday April 15st, 2009 Dan C. Marinescu Email: dcm@cs.ucf.edu Office: HEC 439 B. Office hours: M, Wd 3 – 4:30 PM. TA: Chen Yu Email: yuchen@cs.ucf.edu Office: HEC 354. Office hours: M, Wd 1.00 – 3:00 PM.

Last, Current, Next Lecture Last time: Distributed coordination; algorithms for sharing a communication channel Aloha. Random tree algorithm of Capetanakis. The stack algorithm. Today Distributed coordination; algorithms for sharing a communication channel FCFS algorithm A splitting algorithm for communication with timing constraints. Token passing rings. Asynchronous communication Process Models States and events; local and communication events Local history Local and global states Process coordination and the global predicate evaluation problem Next time: Time, time intrervals Concurrent events Logical clocks