Studies On Resource Access Path In Mobile Video Grid

Mobile Internet and mobile video grid is increasingly widely used in the scope ofvideo streaming services, including video broadcast, video on demand, videosurveillance and other services. The network of mobile video grid has the followingunique features: hetorogenity, terminal mobility and unstable topology; the wirelessnetwork bandwidth still has its significant limitation, so that there are competitionsbetween mobile nodes. However, the video resource access in mobile video gridrequires much more stable bandwidth than the other traditional grid services. To solvethe contradiction, collaborating with the nodes in the grid, supporting quality controlwhen the node accesses video resources, ensuring the actual available bandwidth of theresource access path to satisfy the transmission requirement of the accessed video, andenabling to access the video resources more smoothly when the node is moving, theseare the main research subjects of this paper. Mobile service agent is of key position inthe mobile grid. The path from mobile node to mobile service agent has very essentialimpact on the resource access path. Therefore, this paper studies the discovery andmanagement of resource access path in mobile video grid from three aspects: qualitycontrol of the link in mobile video grid, access path of the mobile service agent and theservice mode of resource access path.The main work of this paper includes:(1) Q-RAPD (QoS-Resource Access Path Discovery) in mobile video grid isproposed. It ensure that during every accessed video resource the request bandwidth ofthe link can satisfy the video bitrate, and the actural network capacity in single-pathmode can reach the range of the theoretical optimum value.(2) Resource access redundant paths in mobile video grid are proposed. It isstudied with using multiple mobile service agents simultaneously to access the samedata in redundant paths and the encoding transmission mode. Compared to single-pathmode, redundant paths can achieve more stable network bandwidth for resource access.(3) Q-RAMPDS (QoS-Resource Access Multiple Path Discovery and Switching) isproposed based on the study of Q-RAPD and redundant paths. In Q-RAMPDS the ratioof every resource access path's bandwidth can change adaptively according to the moving status of the mobile node served. It ensures that the resource access whilemobile node is moving can be smooth, and the network capacity can be maintained at ahigh level.(4) MG-MDF (Mobile Grid Middleware Development Framework) is proposed.The main idea is to construct a middle layer between the reality of the protocol or thegrid middleware module and the operating system or the simulated system. It canreduce the complexity in the mobile grid development, and ensure the consistency ofthe development under different run time.(5) Based on the above studies of theories and experiments, a mobile video gridtestbed is built. The testbed is constructed by cluster streaming server, mobile gateways,wireless cameras and other wired or wireless nodes. In addition to implement the videosurveillance services, it can expand to support other grid video services. It is a scalableplatform.