Adaptive Jitter Buffer Size Management for VoIP

Solution Overview

Problem

VoIP systems face challenges with packet loss, latency, and jitter due to variations in packet transit time over packet-switched networks, which can result in distorted voice communications.

Innovation Solution

The implementation of adaptive jitter buffer size management, where the network device estimates packetization time by calculating the difference between consecutive packet timestamps and adjusts the jitter buffer size in integer increments to mitigate these issues.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the jitter buffer size is increased to absorb delay variations, then packet loss and distortion are reduced, but playout delay increases

Engineering Contradiction:

Improvepacket loss reductionVSAvoidplayout delay

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The jitter buffer size is made dynamic rather than static, allowing it to adapt to changing network conditions. The buffer size is continuously adjusted based on measured inter-arrival times of packets, enabling the system to optimize between packet loss reduction and playout delay minimization in real-time

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system changes the parameter of buffer size based on network conditions. By monitoring the variation in packet inter-arrival times and adjusting the buffer size accordingly, the system can reduce packet loss when network jitter is high while minimizing playout delay when network conditions are stable

Inventive Principle:

Principle #35Parameter changes

2Loss of time

If the jitter buffer size is decreased to reduce playout delay, then real-time performance improves, but packet loss and distortion increase

Engineering Contradiction:

Improveplayout delayVSAvoidpacket loss

Core Design Contradiction:

Loss of timeVSReliability

Solution Approach 1:

The system implements feedback mechanisms by continuously monitoring packet inter-arrival times and using this information to adjust the jitter buffer size. This feedback loop enables the system to respond to network conditions dynamically, reducing packet loss when necessary while maintaining low playout delay

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The jitter buffer size is made dynamic rather than static, allowing it to adapt to changing network conditions. The buffer size is continuously adjusted based on measured inter-arrival times of packets, enabling the system to optimize between packet loss reduction and playout delay minimization in real-time

Inventive Principle:

Principle #15Dynamics

3Device complexity

If static jitter buffer configuration is used, then device complexity is reduced, but adaptability to network changes is limited

Engineering Contradiction:

Improvebuffer management complexityVSAvoidnetwork condition adaptability

Core Design Contradiction:

Device complexityVSAdaptability or versatility

Solution Approach 1:

The jitter buffer system performs self-adjustment by automatically monitoring network conditions and modifying its own buffer size without external intervention. The system calculates inter-arrival times and adjusts the buffer size based on these measurements, enabling adaptive behavior with minimal complexity

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The system changes the parameter of buffer size based on network conditions. By monitoring the variation in packet inter-arrival times and adjusting the buffer size accordingly, the system can reduce packet loss when network jitter is high while minimizing playout delay when network conditions are stable

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS11848846B2Jitter buffer size management

Publication Date: 2023.12.19 MICROSOFT TECHNOLOGY LICENSING LLC

AI summary

Jitter buffer size management is performed by receiving, by a network device, a stream of media content packets. Each packet characterized by a timestamp applied at a source. The device determines, for each of at least one consecutive timestamped packet pair of the stream, a difference between the timestamps of packets in the pair. The device estimates a packetization time (ptime) of the stream as a function of each determined difference. The device adjusts size of the jitter buffer as a function of the estimated ptime.