Routing Device Multicast Forwarding for Cross-Network DLNA Discovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing DLNA-based systems fail to enable automatic discovery of devices across different network segments, leading to poor user experience and inconvenience when electronic devices move between areas covered by different routing devices.
Innovation Solution
Implement a cross-network-segment discovery method where electronic devices perform DLNA delivery and security confirmation, allowing multicast forwarding only after confirmation, and routing devices forward discovery requests between network segments.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If routing devices do not forward multicast packets between network segments to avoid network storm and congestion, then network stability is improved, but device discovery capability across network segments deteriorates
Solution Approach 1:
The routing device applies different forwarding behaviors to different types of packets based on local quality principle. For SSDP discovery packets, it enables multicast forwarding to maintain device discovery capability. For other data packets, it maintains normal routing behavior. This selective approach resolves the contradiction by applying the appropriate quality control to specific local scenarios without affecting overall network stability.
Solution Approach 2:
The routing device dynamically adjusts its packet forwarding behavior based on packet type and destination. When an SSDP discovery packet is detected, the routing device temporarily enables multicast forwarding to allow cross-network segment discovery. After the discovery process completes, it returns to normal routing mode. This dynamic adjustment allows the system to adapt between stability and discovery capabilities as needed.
2Adaptability or versatility
If routing devices enable multicast forwarding for all packets, then device discovery across network segments is improved, but network storm and congestion increase
Solution Approach 1:
The routing device applies local quality control by enabling multicast forwarding only for specific packet types (SSDP discovery packets) and not for all packets. This selective enablement allows improved device discovery capability across network segments while preventing network storm and congestion that would result from universal multicast forwarding.
Solution Approach 2:
The routing device extracts and processes only the necessary discovery packets through a special handling mechanism. By separating discovery packet processing from general data packet routing, the system can enable enhanced discovery capability for relevant packets while maintaining normal, more stable routing behavior for other traffic, thus avoiding network-wide multicast storm.
3Stability of the object's composition
If routing devices use unicast mode for all communication, then network stability is improved, but device discovery efficiency deteriorates
Solution Approach 1:
The routing device dynamically switches between unicast and multicast modes based on the specific communication needs. For SSDP discovery packets requiring broad notification, it uses multicast mode to improve discovery efficiency. For other stable routing scenarios, it maintains unicast mode. This dynamic mode switching resolves the contradiction between network stability and discovery efficiency.
Solution Approach 2:
The routing device changes the packet forwarding parameter (multicast vs. unicast mode) based on packet type and discovery requirements. When discovery efficiency is needed, it changes to multicast mode; when stability is prioritized, it returns to unicast mode. This parameter adjustment allows the system to optimize for different operational goals without permanent compromise to either stability or efficiency.
Data Source
Figure 1~2A
Figure 2B
Figure 2C
AI summary
This application relates to a cross-network-segment discovery method and system, and a routing device. The method includes: An electronic device A sends, to an electronic device B, a DLNA delivery message that includes a URL and an identifier of the electronic device B. The electronic device B plays content corresponding to the URL. After the electronic device A moves from an area A to an area B, the electronic device A disconnects from a routing device A, and connects to a routing device B. The electronic device A sends, to the routing device B, a first request message that includes a fixed multicast address. The routing device B forwards the first request message to the routing device A. The routing device A sends the first request message in a multicast mode within a range of a first multicast address. The electronic device B sends a first response message to the electronic device A by using the routing device A and the routing device B. The electronic device A discovers the electronic device B. In this way, cross-network-segment automatic discovery may be implemented, to provide convenience for a user and improve user experience.