A Survey of Bandwidth Optimization Techniques and Patterns in VoIP Services and Applications

TL;DR

This survey reviews various bandwidth optimization techniques for VoIP, highlighting silence suppression, header compression, and codec improvements, and discusses their effectiveness over 15 years.

Contribution

It provides a comprehensive overview of bandwidth optimization methods in VoIP from 1999 to 2014, emphasizing the impact of header compression and codec enhancements.

Findings

Voice Activity Detection reduces transmission during silence.

Header compression significantly decreases packet size.

Codec improvements enhance VoIP performance over broadband.

Abstract

This article surveys the various techniques adopted for optimising bandwidth for VoIP services over the period 1999-2014. The improvement of bandwidth can be realized through; silence suppression measure of repressing the silent portions (packets) in a voice conversation using Voice Activity Detection algorithm; by so doing, the transmission rate during the inactive periods of speech is reduced, and thus, the mean transmission rate can be reduced. A second measure is packet header reduction which defines a process of multiplexing and de-multiplexing packet headers to curb excesses. Voice/ Packet Header compression is considered the most productive of all the techniques, offering a scheme where VoIP packets are compressed from the 40 bytes of size to a smaller byte size of 2 bytes. When combined with aggregation, compression potentially yields a compressed size of up to 1 byte. In either case, bandwidth save is reached using compression and decompression codecs of varying data and bit rates. It is envisaged that an improvement in the performance of codecs would yield a better result in terms of enhancing results favourably in Voice over broadband networks