Proxy Content Delivery with Delayed Multicast Channel Joining
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current hybrid solutions for content delivery using multicast and unicast face issues with latency differences between channels, leading to missing segments and playback stalls on low-bandwidth connections, causing interruptions and poor user experience.
Innovation Solution
A method and network element that manages content delivery by preemptively requesting segments via unicast before joining a multicast channel, storing data until needed, and using a retransmission server to fill gaps, ensuring timely delivery without significant bandwidth reduction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If multicast delivery is used to improve bandwidth efficiency, then network bandwidth utilization is improved, but latency increases and segments may be received ahead of unicast segments causing playback interruptions
Solution Approach 1:
The proxy receives unicast segments from the content server before the corresponding multicast segments become available, storing them in a buffer. This preliminary reception ensures that when multicast delivery begins, the proxy already has segments ready to deliver to the client, eliminating playback interruptions caused by timing mismatches between multicast and unicast delivery channels.
2Stability of the object's composition
If the proxy receives both multicast and unicast data simultaneously to fill gaps, then segment continuity is improved, but bandwidth consumption increases causing playback stalls on low-bandwidth connections
Solution Approach 1:
The proxy proactively requests and receives unicast segments in advance before switching to multicast delivery. By pre-receiving segments through unicast and buffering them, the proxy eliminates the need to simultaneously receive both unicast and multicast data, thereby maintaining segment continuity while avoiding excessive bandwidth consumption on low-bandwidth connections.
3Loss of time
If unicast delivery is used to ensure timely segment delivery, then segment delivery timing is improved, but network bandwidth efficiency deteriorates
Solution Approach 1:
The proxy uses unicast delivery to pre-receive segments from the content server before multicast delivery begins. This preliminary unicast reception ensures timely segment availability in the proxy's buffer. Once pre-loaded, the proxy switches to multicast delivery for subsequent segments, thereby achieving both timely delivery (through preliminary unicast) and network bandwidth efficiency (through multicast delivery).
Solution Approach 2:
The proxy acts as an intermediary between the content server and the client device. It receives segments via unicast from the content server, buffers them, and then delivers them to the client using multicast. This intermediary role allows the system to combine the advantages of both unicast (timely delivery control) and multicast (bandwidth efficiency) by decoupling the reception and delivery phases.
Data Source
AI summary
A method of managing content delivery to a client device by a proxy, where the content is made up of a sequence of segments. The proxy starts off by receiving content requests from the client device over unicast, and fulfilling those requests by forwarding them to a content server, and receiving that content before forwarding onto the client device. At some stage, the proxy determines that a multicast channel should be joined to more efficiently receive the required content. However, the multicast channel is likely to be ahead of the available unicast data. Therefore, a multicast join command is delayed until the proxy has taken steps to obtain subsequent content by unicast faster than that content is being requested by the client device, so that the obtained content has caught up with the content available on the multicast channel. The proxy stores this content and uses it to respond to requests from the client device. Only then does the proxy take action to join the multicast channel.