Name
Abstract | ||
|---|---|---|
The emergence of OpenFlow-capable switches enables exciting new network functionality, at the risk of programming errors that make communication less reliable. The centralized programming model, where a single controller program manages the network, seems to reduce the likelihood of bugs. However, the system is inherently distributed and asynchronous, with events happening at different switches and end hosts, and inevitable delays affecting communication with the controller. In this paper, we present efficient, systematic techniques for testing unmodified controller programs. Our NICE tool applies model checking to explore the state space of the entire system--the controller, the switches, and the hosts. Scalability is the main challenge, given the diversity of data packets, the large system state, and the many possible event orderings. To address this, we propose a novel way to augment model checking with symbolic execution of event handlers (to identify representative packets that exercise code paths on the controller). We also present a simplified OpenFlow switch model (to reduce the state space), and effective strategies for generating event interleavings likely to uncover bugs. Our prototype tests Python applications on the popular NOX platform. In testing three real applications--a MAC-learning switch, in-network server load balancing, and energy-efficient traffic engineering--we uncover eleven bugs. |
Year | Venue | Keywords |
|---|---|---|
2012 | NSDI | large system state,openflow switch model,model checking,unmodified controller program,possible event ordering,centralized programming model,event handler,single controller program,openflow application,state space,entire system,computer science,openflow,testing |
Field | DocType | Citations |
Asynchronous communication,Control theory,Model checking,Programming paradigm,Computer science,Load balancing (computing),Computer network,Real-time computing,Event (computing),OpenFlow,Symbolic execution,Distributed computing | Conference | 183 |
PageRank | References | Authors |
11.61 | 23 | 5 |
Name | Order | Citations | PageRank |
|---|---|---|---|
| Marco Canini | 1 | 857 | 60.21 |
| Daniele Venzano | 2 | 221 | 16.42 |
| Peter Perešíni | 3 | 375 | 21.98 |
| Dejan Kostic | 4 | 1707 | 119.11 |
| Jennifer Rexford | 5 | 14378 | 1195.34 |