Network Latency Measurement via Timestamped Test Packets
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for measuring Ethernet circuit latency do not account for multiple segments within a network path, requiring numerous tests and excessive messaging to isolate segment delay, which is time-consuming and inefficient.
Innovation Solution
A method that generates a test packet with timestamps to measure latency between devices, allowing each device to calculate segment delays and store them for later retrieval, enabling end-to-end and segment-by-segment latency determination without increasing messaging overhead.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional end-to-end latency measurement methods are used, then measurement capability is provided, but segment-by-segment latency cannot be isolated without numerous tests and excessive messaging
Solution Approach 1:
The patent divides the end-to-end latency measurement into individual segment measurements by having each network device along the path record its own latency contribution. Test packets carry timing information that allows each device to measure and report only its segment's latency, eliminating the need for multiple full-path tests to isolate individual segments.
Solution Approach 2:
The patent introduces an intermediary mechanism where network devices along the path act as measurement points that record and report segment-specific timing data. This intermediary approach allows centralized collection of segment latency information without requiring numerous coordinated tests between endpoint pairs.
2Loss of information
If segment-by-segment latency measurement is implemented through traditional methods, then detailed segment information is obtained, but messaging overhead increases excessively
Solution Approach 1:
The patent merges the segment latency measurement function with existing test packet traffic. Instead of creating separate messaging protocols for each segment measurement, the solution embeds timing stamps and measurement data within standard test packets that already traverse the network path, thereby collecting segment information without additional messaging overhead.
Solution Approach 2:
The test packets serve multiple functions: they carry timing stamps for endpoint-to-endpoint latency measurement, enable intermediate devices to record segment-specific timing data, and provide synchronization information. This multi-functionality allows segment-by-segment measurement using the same messaging infrastructure as end-to-end measurement.
3Measurement precision
If multiple tests are performed to isolate segment delays, then segment latency information is obtained, but measurement time and complexity increase
Solution Approach 1:
The patent applies preliminary action by pre-positioning timing stamps in test packets at the source device before transmission. Intermediate devices along the path use these pre-existing timestamps to calculate their segment's latency contribution without requiring additional coordination or multiple tests, thereby obtaining precise segment isolation in a single pass.
Data Source
AI summary
A method of determining the latency of path segments in a communication network that uses multi-bit data packets comprises generating a test packet for use in determining the latency of path segments in the network; transmitting the test packet from a first device coupled to the network; storing in the test packet the time when a preselected bit in the test packet is transmitted from the first device; when the test packet is received by a second device coupled to the network, storing in the second device at least one of (a) the time when a preselected bit in the test packet is received by the second device and (b) the difference between (i) the time when the preselected bit in the test packet is transmitted from the first device and (ii) the time when the test packet is received by the second device.