Distributed Algorithms

Calendar

SES #	TOPICS	KEY DATES
1	Course overview. Synchronous networks. Leader election in synchronous ring networks.	Homework 1a out
2	Leader election in rings. Basic computational tasks in general synchronous networks: leader election. Breadth-first search. Broadcast and convergecast. Shortest paths.
3	Spanning trees. Minimum spanning trees.	Homework 1b out
4	Fault-tolerant consensus. Link failures: the two generals problem. Process failures (stopping, Byzantine). Algorithms for agreement with stopping and Byzantine failures. Exponential information gathering.
5	Number-of-processor bounds for Byzantine agreement. Weak Byzantine agreement. Time bounds for consensus problems.	Homework 1 due Homework 2a out
6	k-set-agreement. Approximate agreement. Distributed commit.
7	Asynchronous distributed computing. Formal modeling of asynchronous systems using interacting state machines (I/O automata). Proving correctness of distributed algorithms.	Homework 2b out
8	Non-fault-tolerant algorithms for asynchronous networks. Leader election, breadth-first search, shortest paths, broadcast and convergecast.
9	Spanning trees. Gallager et al. minimum spanning trees.	Homework 2 due Homework 3a out
10	Synchronizers. Synchronizer applications. Synchronous vs. asynchronous distributed systems.	Homework 3b out
11	Time, clocks, and the ordering of events. State-machine simulation. Vector timestamps.
12	Stable property detection. Distributed termination. Global snapshots. Deadlock detection.	Homework 3 due Homework 4a out
13	Asynchronous shared-memory systems. The mutual exclusion problem. Mutual exclusion algorithms.
14	More mutual exclusion algorithms. Bounds on shared memory for mutual exclusion. Resource allocation. The Dining Philosophers problem.	Homework 4b out
15	Shared-memory multiprocessors. Contention, caching, locality. Practical mutual exclusion algorithms. Reading/writing locks.
16	Impossibility of consensus in asynchronous, fault-prone, shared-memory systems.	Homework 4 due Homework 5a out
17	Atomic objects
18	Atomic snapshot algorithms. Atomic read/write register algorithms.	Homework 5b out
19	List algorithms: locking algorithms, optimistic algorithms, lock-free algorithms, lazy algorithms.
20	Transactional memory: obstruction-free and lock-based implementations.	Homework 5 due Homework 6a out
21	Wait-free computability. The wait-free consensus hierarchy.	Homework 6b out
22	Wait-free vs. f-fault-tolerant atomic objects. Boosting fault-tolerance.
23	Asynchronous network model vs. asynchronous shared-memory model. Impossibility of consensus in asynchronous networks. Failure detectors and consensus. Paxos consensus algorithm.	Homework 6 due Homework 7 out
24	Self-stabilizing algorithms
25	Timing-based systems. Modeling and verification. Timing-based algorithms for mutual exclusion and consensus. Clock synchronization.	Homework 7 due