Congestion problem of IP over MPLS on the label overload

MPLS is a forward scheme. In the Open Systems Interconnection (OSI) seven-layer model, it is between Layer 2 (L2, link layer) and Layer 3 (L3, network layer). Each MPLS packet has a header. The header contains a 20 bit label, a 3 bit class of service (COS) field, a 1-bit label stack indicator and an 8-bit TTL field. The MPLS header is encapsulated between the link layer header and the network layer header. The label stack is represented as a sequence of “label stack entries”. Each label stack entry is represented by 4 octets. The label stack entries appear after the data link layer headers, but before any network layer headers. In IP over MPLS, labeled IP packet traffic is overloaded in respect to unlabeled IP packet traffic. In this paper, by varying the packet rate and measuring the throughput of the flows, we analyze the performance of labeled IP packet traffic and unlabeled IP packet traffic in IP over MPLS. Also in this paper, we suggest a change to the label allocation algorithm and explore the effect of the change on IP over MPLS