3GPP's Dynamic Adaptive Streaming over HTTP (DASH) specifications were developed in Rel-9 and Rel-10 and are available in TS 26.247
. Despite being integrated into the PSS architecture, the specifications have significant flexibility for deployments also outside the 3GPP services. This has been recognized by other organizations such as MPEG and Open IPTV Forum. In continuous alignment efforts, 3GPP and MPEG have developed a generic format for Dynamic Adaptive Streaming over HTTP (DASH).
These specifications serve an urgent need: With the evolution of radio access technologies towards HSPA & LTE higher data rates are provided allowing more feature rich services with higher quality and access to multimedia services has grown significantly. And the most popular multimedia services today are services delivered over HTTP. Serving content from standard HTTP-servers has many advantages in terms of deployment costs and convergences with regular web services.
With the completion of the specifications, first deployments of services based on DASH and similar technologies are happening. The experiences from initial deployments of massively scalable video streaming delivery over HTTP and advanced radio access technologies result in new use cases, demands and requirements. Improvements for the support of DASH when delivered over 3GPP networks and architectures are expected to be necessary and deployments guidelines are important.
Considered improvements are in the area of improved user experience, improved bandwidth efficiency or more efficient delivery over HTTP-caching infrastructures. Furthermore, the combination of DASH with other services and technologies is an ongoing challenge and effort. Not limited to this, but some examples are the delivery of DASH over different 3GPP radio access networks, the combination with presentation technologies such as HTML-5, the support of advanced content protection schemes, or the support for QoS in 3GPP networks.
Service improvements might not require additional TS 26.247
specification work, but do require a detailed analysis of the envisaged use cases, the resulting requirements, the ability to solve these use cases with the existing 3GPP and/or other existing specifications and provide guidelines and deployment examples. The analysis of the use cases may lead to additional specification work, but this should first be identified and justified from the above analysis.
The present document covers
deployment guidelines for DASH in 3GPP networks and architectures,
use cases for the improved support of DASH in 3GPP networks and architectures as well as requirements to support those use cases,
recommendations for potentially necessary normative specification work in 3GPP,
recommendations for the documentation of potentially informative guide lining work.
full Table of Contents for TR 26.938 Word version: 15.0.0