Abstract: Multi-protocol label switching is a great solution for problems like scalability, quality-of-service, bandwidth-management, and traffic engineering faced by networks. It is believed that MPLS make an internet environment more efficient for more customer satisfaction. In this paper, our main focus is on the load congestion and blocking probability when traffic is overloaded. In the network load congestion occur. When network resources are too short to accommodate the offered load. It means that the system is completely occupied and the new incoming call undergoes in blocking state. In this paper survey on load congestion and blocking probability is done. This paper also represents MPLS contributing high scalability in computer networks.

Keywords: Blocking Probability, Traffic Congestion, Erlang, Traffic Engineering, Load Balancing.