Optimization of the Low-Speed Link Throughput for Voice Services

The weak point of the field network is represented by E12 low-speed relay links. The situation requires savings of the bandwidth. For this purpose, the necessary bandwidth for voice transmission up to the level of the physical layer has been analyzed. As a suitable solution of network throughput increase, we propose the change of a Voice Payload Size. After finding the optimal Voice Payload Size, tests were carried out to verify the impact of the Voice Payload Size on call quality. A packet loss rate is chosen as a parameter for modelling real traffic. To obtain the expected voice quality, the E-model according to the G.107 Recommendation is applied. The theoretical results are compared with practical measurements, when using the proprietary Cisco Packet Loss Concealment algorithm to evaluate the voice quality. The results obtained have confirmed the suitability of the solution.