Isochronous Packet Router Switching via RTP Timestamp Parsing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing IP routers struggle with isochronous switching of packetized media streams, often resulting in visible artifacts or 'glitching' due to unawareness of the vertical interval during route changes, leading to inefficiencies and high overhead costs in bandwidth and orchestration requirements.
Innovation Solution
A method and system that parse the RTP header within IP datagrams to extract the RTP timestamp, allowing for precise switching at the point of timestamp change, enabling isochronous switching by changing the forwarding address based on detected changes in the timestamp value.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If IP routers change routes based on IGMP command sequence or SDN command, then routing flexibility is improved, but switching precision deteriorates because the routers are unaware of the vertical interval
Solution Approach 1:
The patent introduces an RTP timestamp parser as an intermediary component that extracts timing information from packet headers. This parser acts as a mediator between the routing control and the switching mechanism, providing precise vertical interval awareness without requiring changes to the underlying IGMP or SDN protocols. The timestamp information serves as an intermediary signal that triggers switching at the correct moment.
Solution Approach 2:
The system implements feedback by continuously monitoring RTP timestamps in incoming packets and using this information to trigger route changes at precise moments. The timestamp value provides real-time feedback about the current video frame timing, allowing the router to synchronize switching operations with the vertical blanking interval and avoid visible artifacts.
2Speed
If switching occurs during active picture portion, then switching speed is improved, but visual quality deteriorates due to visible artifacts or glitching
Solution Approach 1:
The system performs preliminary action by continuously parsing and monitoring RTP timestamps in advance of any switching decision. This allows the router to identify the upcoming vertical blanking interval in advance and prepare for switching during that safe window, rather than reacting after a switch has already caused visible artifacts.
3Measurement precision
If upstream orchestration is implemented to generate pre-select signals, then switching accuracy is improved, but bandwidth consumption deteriorates due to requiring twice the bandwidth
Solution Approach 1:
The router performs self-service by autonomously parsing RTP timestamps from the incoming packet streams and using this information to trigger switching operations. This eliminates the need for external upstream orchestration systems to generate pre-select signals, thereby avoiding the doubling of bandwidth requirements while maintaining precise switching accuracy.
4Adaptability or versatility
If port address changes are implemented in IP 5-tuple, then switching capability is improved, but system complexity deteriorates due to requiring orchestration with every source equipment
Solution Approach 1:
The RTP timestamp parser serves as an intermediary that provides a universal switching trigger mechanism independent of source equipment. Instead of requiring customization and orchestration with every source device to change port addresses, the system uses the universally present RTP timestamp in video packets to trigger switching, greatly simplifying the system architecture.
Data Source
AI summary
An IP router capable of isochronous switching of a packetized media stream. According to an example, the IP router parses the RTP header within an incoming IP datagram to extract the RTP time stamp, which provides a time value for a unique IP Flow. By inspecting the header, the IP router can switch the flow at the point in time that the RTP time stamp value changes, or matches a target value. In one aspect, the IP router looks for the change in the RTP time stamp value and performs the switch based on the detected change. In another aspect, the IP router performs the switch at a specified time stamp value that can be unique to a group of signals or based on a common “sync” value published to all the ports of the IP router.