Today's Internet service providers are facing a challenging problem to keep pace with the growing Internet traffic. As traffic is growing at a rate of almost twice every year, service providers' core networks are getting congested and they are failing to satisfy the needs of the customers. Our study is carried out to provide a basis for the solution towards congestion control for the service providers. We have tested the performance of a congested network after changing its average node degree. We have simulated the NSFNET with its average node degree of 3. When traffic in a network increased and any link got congested, the node that was responsible for congestion was found out. After finding out the node, its degree was increased. We also found out the percentage change in the performance of the congested link by keeping on increasing the node degree. We have found out optimal points up to which node degree can be increased to get improved network performance.