Cache Server Bandwidth Adaptation for Video Streaming
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional content distribution systems fail to adapt to varying mobile network bandwidth, leading to interrupted video playback, unnecessary data delivery, and impaired user experience, especially when distributing high-quality video content over mobile networks.
Innovation Solution
A content distribution system with multiple cache servers that dynamically adjust bit rates of video content based on estimated mobile network bandwidth and buffer capacity, ensuring seamless playback by controlling transmission timing and avoiding unnecessary data delivery.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional content distribution systems distribute video content with a fixed bit rate, then the content can be transmitted continuously, but the mobile network bandwidth varies in time and the content cannot be transmitted when bandwidth is less than the content bit rate, causing video playback to stop or audio to be interrupted
Solution Approach 1:
The system dynamically switches between multiple bit rate versions of the same content based on real-time mobile network bandwidth conditions. Instead of using a fixed bit rate, the distribution system adapts the content bit rate to match the available network bandwidth, preventing playback interruptions while maintaining optimal video quality.
Solution Approach 2:
The system changes the bit rate parameter of the video content according to network conditions. By preparing multiple versions of content with different bit rates and switching between them based on measured bandwidth, the system ensures continuous playback while adapting to varying network capacity.
2Reliability
If conventional content distribution systems deliver all content data to the terminal, then the terminal has sufficient data for playback, but unnecessary data that is not needed for current viewing is delivered, wasting limited mobile network bandwidth
Solution Approach 1:
Instead of delivering all content data in advance, the system delivers only the necessary portion of content data required for current and near-future playback. By calculating the needed data amount based on playback position and timing, the system avoids wasting bandwidth on unnecessary data while ensuring sufficient data is available for continuous playback.
3Productivity
If multiple cache servers are deployed to distribute content to various mobile terminals, then content can be delivered to different terminals, but determining which cache server stores the requested content requires efficient lookup mechanisms
Solution Approach 1:
The system uses a hash function to deterministically map content identifiers to specific cache servers. When a terminal requests content, the server calculating unit computes which cache server should hold the content based on the content ID, and the terminal is directed to that specific server. This feedback mechanism ensures efficient content location without requiring complex distributed storage management.
Data Source
AI summary
A cache server comprises a storage unit that stores managed content held by a storage apparatus in a mobile network, determines, from among a plurality of cache servers provided in the mobile network, a cache server that stores content(s) requested by a mobile terminal, using information included in a content request message from the mobile terminal, estimates a bandwidth of the mobile network based on a signal from the mobile terminal, reads a file with a bit rate not exceeding the bandwidth among a plurality of files having the requested content(s) with different bit rates, from the determined cache server, and transmits the read file to the mobile terminal while controlling timing of transmission in accordance with a buffer capacity of the mobile terminal.