Comparison of Skype VoIP quality over 3G with mobility: A case study of fair usage policy effects

This paper presents a comparative study of VoIP quality over 3G networks, based on Fair Usage Policy (FUP) and Access Unlimited Internet Service (AUIS) provided by two main 3G operators using Skype and a form of mobility usage, defined as semi-dynamic tests. The tests were conducted on electric train called BTS Skytrain (Sukhumvit line). After gathering data of degraded speech files from the tests with Thai speech files, they were processed using a tool called Perceptual Evaluation of Speech Quality tool (PESQ) to obtain the values of Mean Opinion Score (MOS), whereas, data of major Quality of Service (QoS) parameters, consisting of loss, delay and jitter were also gathered. Then, it has been analyzed and found that VoIP quality has been impacted by FUP because QoS parameters and MOS tend to be worse than the values from AUIS.