Proxy Cache Media Delivery Error Recovery

Solution Overview

Problem

Current media delivery systems face limitations in serving multiple client devices due to the unicast nature of server-client communications, which leads to bandwidth inefficiencies and constraints on server capacity, while broadcast channels lack error recovery mechanisms essential for coded video data.

Innovation Solution

A media delivery system that includes a media source, a proxy cache, and client devices, where the media source broadcasts coded segments to proxy caches in a broadcast channel, allowing clients to first request segments from the proxy cache, which can recover from transmission errors and reduce server loading by intercepting and caching communications.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If unicast transmission is used for media delivery, then error recovery capability is improved, but server capacity and bandwidth efficiency deteriorate

Engineering Contradiction:

Improveerror recovery capabilityVSAvoidserver capacity

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent segments the media delivery function by dividing the system into multiple proxy caches distributed across the network. Each proxy cache handles a portion of the client requests, segmenting the server load and enabling the main server to serve more clients without proportionally increasing unicast channel usage.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent introduces proxy caches as intermediary components between the media server and client devices. These proxies receive broadcast transmissions and provide unicast error recovery services locally, eliminating the need for direct unicast channels between the main server and each client while maintaining error recovery capability.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Productivity

If broadcast channel is used for media delivery, then server loading is reduced, but error recovery capability deteriorates

Engineering Contradiction:

Improveserver loadingVSAvoiderror recovery capability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent introduces proxy caches as intermediary components between the media server and client devices. These proxies receive broadcast transmissions and provide unicast error recovery services locally, eliminating the need for direct unicast channels between the main server and each client while maintaining error recovery capability.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent creates local copies of coded segments at distributed proxy caches. These copies enable clients to receive media content via efficient broadcast transmission while allowing local proxies to provide error recovery services using their stored segment copies, eliminating the need for continuous unicast error recovery channels.

Inventive Principle:

Principle #26Copying

3Reliability

If multiple unicast transmissions are provided to multiple clients, then error recovery for each client is improved, but bandwidth consumption and server capacity deteriorate

Engineering Contradiction:

Improveerror recovery for each clientVSAvoidbandwidth consumption

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The patent merges the error recovery function into the broadcast channel by having multiple proxy caches listen to the same broadcast transmission. This allows all proxies to obtain segments simultaneously through a single broadcast channel rather than requiring separate unicast channels for each client, significantly reducing bandwidth consumption while maintaining individual error recovery capability.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent creates local copies of coded segments at distributed proxy caches. These copies enable clients to receive media content via efficient broadcast transmission while allowing local proxies to provide error recovery services using their stored segment copies, eliminating the need for continuous unicast error recovery channels.

Inventive Principle:

Principle #26Copying

Data Source

PatentEP2957052B1Media delivery service protocol to support large numbers of client with error failover processes

Publication Date: 2022.07.20 APPLE INC

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AI summary

A media delivery service may include a media source, a proxy cache and one or more client devices. The media source may generate coded segments from an input media stream and develop a playlist identifying network locations of the segments. The media source may broadcast the coded segments and their storage locations to a proxy cache in a broadcast channel. The proxy cache may store successfully received coded segments and develop a mapping table identifying the segments' network locations. The client may request segments from the proxy cache based on the received playlist form the media source. If the proxy cache does not store a requested segment, it may so notify the client and the client may request the segment from the media source.