Network delay and bandwidth estimation for cross-device synchronized media

Driven by the growth in mobile phone and tablet ownership, recent years have witnessed an increasing trend towards coordinated media experiences across multiple devices. The quality of experience (QoE) over such new generation applications is dictated by the Quality of Service (QoS) of underlying networks. Inevitable network delay and bandwidth fluctuations affect the communications and media synchronization between connected devices. Therefore, network measurement is becoming the key to providing essential information for the QoE assurance of cross-device synchronized media. Among many network measurement techniques, packet probing is considered as the most effective for end-to-end evaluations. Packet probing may seem straightforward but it requires a good understanding of the methodologies and how the results should be interpreted. This chapter provides a guidance and some best practices in packet probing, accompanied with a use case where delay measurement enhances cross-device media synchronization and the QoE of an immersive media application.