In the past decade, Quality of Service (QoS) parameters have posed great challenges for network operators. This is partly because of the growth in network varied traffic demands. QoS is a mechanism to assure that audio and video data traverse the network with minimum delay. If network QoS is not in place, IP voice or videoconferencing calls will be unreliable, inconsistent, and often unsatisfactory. Quality is specified as \"The collective effect of service performances, which determine the degree of satisfaction of a user of a service\".