Surajudeen-Bakinde, N. TAdeniji, K. AOyeleye, S. OZakariyya, O. SOlayanju, S. AUsman, A. M2021-03-312021-03-312020-06-30Surajudeen-Bakinde, N. T., Adeniji K. A., Oyeleye, S. O., Zakariyya, O. S., Olayanju, S. A., & Usman, A. M. (2020): Assessment of Quality of Service of G.S.M. Networks in Ilorin Metropolis, Nigeria. ABUAD Journal of Engineering Research and Development (AJERD), 3(1):154-162, Published by Afe Babalola University, Ado-Ekiti, Nigeria. Available online at http://ajerd.abuad.edu.ng/volume-3-issue-1-preview/2645-2685http://hdl.handle.net/123456789/4644A journal articleFollowing the rollout of GSM services across Nigeria, the socio-economic landscape of the country has been positively altered. Its explosive growth has brought huge revenues to the operators, as well as the government and at the same time benefited the citizens in many ways. However, the principal developmental factors that has continued to mar these benefits is the aggressive complaints from GSM subscribers regarding the horrible Quality of Service (QoS) rendered by the GSM operators across the country. As the number of subscribers of GSM in Nigeria increased, congestion rates also increased and there has been a huge demand for a decent QoS in the country. In this study, three key performance indicators (KPI) parameters, call setup success rate (CSSR), received signal level (RSL) and call drop rate (CDR) were used in assessing the performance of two of the major GSM networks in Ilorin Metropolis of Nigeria, which have been tagged Network “A” and Network “B”. A and B monitored are far from providing reliable services to Nigerians. None of the networks in the study met the ≥ 98% CSSR required by the N.C.C. regulations, and none met the ≤ 2% CDR required by the N.C.C. regulations. The problems GSM operation encountered have been attributed to a number of challenges, with cited faults ranging from the Network providers, to regulatory agencies, and even to the Nigerian Government.enGlobal System for Mobile CommunicationQuality of ServiceKey Performance IndicatorsNetwork CongestionReceived Signal LevelArticle