Growing demand for Voice over Internet Protocol (VoIP) services has motivated the solution providers to look for technologies that provide better, more manageable and efficient delivery of voice traffic. Multi-Protocol Label Switching (MPLS) is one such technology. Voice over Internet Protocol over Multi-Protocol Label Switching (VoIPoMPLS) is a relatively new idea in facilitating voice traffic between access networks over an MPLS backbone as opposed to VoIP that uses the best-effort Internet for transporting voice traffic. An MPLS network provides comprehensive options for Quality of Service (QoS) and signaling of voice traffic compared to Frame Relay and IP networks. IP is a major competitor of MPLS in the access networks as voice may already be in IP packets when it reaches the Integrated Access Device. In this thesis we show the benefit provided by an MPLS Network over an IP Network in terms of delay, jitter, throughput and other performance metrics like CPU utilization, virtual memory and interrupts/sec for voice traffic.