OverviewIn this project, we seek a new design of tiled display wall middleware that are aware of network condition and tries to avoid instabilities. We modified tiled display wall middleware to be able to detect network failures and packet buffering mechanism based on OpenFlow technology, one of the Software Defined Network implementation. With the modified version of SAGE, a visualization application can detect a network failure, and change network path according to the circumstances. And also the packet buffering mechanism can compensate dropping packets, that might lead to corruption of video frames.
SAGETiled display wall usually consists of multiple displays and backend PC cluster to render or receive high-resolution images that appear on the displays. SAGE (Scalable Adaptive Graphics Environment) is a middleware designed to control tiled display walls. Notable features of SAGE include distributed rendering, display number scalability, and multiple viewing applications. We believe that these features are very important for spreading and encouraging e-Science movement.
To achieve stable display of high-resolution video contents from a remote site, stability of data streaming over network is essential. However, with current design of SAGE, network is used as-is and there is no mechanism to handle unexpected network instabilities. As a result, such instability may result in corruption of video frames, or termination of video streaming.
OpenFlowSDN (Software Defined Network) is a newly-emerged network concept that allows us to separate the network control plane from the data transfer plane. That can help network administrators to manage network resources in centralized manner. And also SDN enables us to realize flexible control of network resources, such as redundant pathway, packet buffering and so on. OpenFlow is the most popular SDN implementation which is being standardized by the Open Networking Foundation. The OpenFlow protocol, which is used to split the control plane from the data plane, has been affected by SDN concept.
Trema is one of OpenFiow controller framework, which provides easy-to-use framework for developing OpenFlow controller in Ruby and C language. We implement detecting and avoidance a network failure with SAGE and Trema.