Optimizing multimedia streaming in 3GPP mobile broadband networks (e.g. HSPA, LTE) in terms of user experience and network resource utilization is one of the most important topics for mobile network operators. The primary reason is that streaming services consume more than half of the total bandwidth. Before designing new concepts and solutions it is fundamental to understand in detail the performance and behavior of multimedia applications for the mobile access. For this reason we have carried out several field experiments to obtain knowledge about typical bandwidth consumption, ability to adapt video bit-rate to changed network conditions, protocol and other service specific issues for the most popular over-the-top and managed video services. We have detected that observed data rates apart from the video encoding and the specific content also depend on client and server implementations. Surprisingly, support for rate adaptation in current implementations of managed and over-the-top streaming services is not very common, in some cases with limited feature set. From the obtained results we conclude that measurements need to continue with a shift from field experiments to lab environment in order to obtain further knowledge of streaming characteristics, which could not be revealed in the current measurements.
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