Evaluation of VoIP Service Quality on Campus Networks at Ahmadu Bello University, Zaria

Voice over Internet Protocol technology enables cost-effective voice communication over data networks and has gained significant adoption in Nigerian educational institutions as a supplement to traditional telephony. This study evaluates the quality of VoIP service experienced on campus networks at Ahmadu Bello University, Zaria, Kaduna State, North West Nigeria. A quantitative measurement study design was adopted, using open-source network analysis tools to assess mean opinion score, packet loss, jitter, and end-to-end delay across the university's campus local area network and wireless LAN infrastructure. Measurements were taken during peak academic hours and off-peak periods across six campus zones over four weeks. VoIP calls were simulated using software-based clients conforming to the SIP protocol standard. Mean opinion scores averaged 3.1 during peak hours, falling below the ITU-T G.107 recommended minimum of 3.5 for acceptable call quality. Jitter exceeded the 30 millisecond threshold acceptable for VoIP at 64% of measurement points during peak periods. The main campus wireless backbone was identified as the primary congestion point, with insufficient quality of service traffic prioritization mechanisms in place. Packet loss rates of up to 4.8% were recorded on high-traffic segments. Recommendations include implementation of differentiated services code point marking for VoIP traffic, upgrade of wireless access points to Wi-Fi 6 standard, and dedicated bandwidth reservation for real-time communication applications. Keywords: VoIP quality, campus network, jitter, mean opinion score, Ahmadu Bello University.