The demand for playing the video with the highest quality possible leads video streaming companies to utilize network-based solutions and server assistance. As being one of the popular technology in video streaming area, HTTP adaptive video streaming systems can benefit from the emerging network technologies such as SDN and NFV. Such multimedia systems require the management of network resources efficiently to be able to provide acceptable service. In this paper, we propose a multimedia service management architecture that focuses on migration one of the most crucial components of such systems, virtualized caches. SDN controller gathers underlay network statistics and based on real-time network condition determines the optimal location for virtual cache and/or migrate it when network conditions change. We focus on hand-off affects the perceptual quality when clients migrate from one cache to another. The proposed approach was evaluated using the Mininet Emulator and its performance was given comparatively. The performance results show that the combination of SAND (Server and Network Assisted DASH) features with the advantage of the NFV-SDN technology can provide good service to its users.