Over the last few years, the Internet has evolved into a ubiquitous network and inspired the development of a variety of new applications in business and consumer markets. These new applications have driven the demand for increased and guaranteed bandwidth requirements in the backbone of the network. In addition to the traditional data services currently provided over the Internet, new voice and multimedia services are being developed and deployed. The Internet has emerged as the network of choice for providing these converged services. However, the demands placed on the network by these new applications and services, in terms of speed and bandwidth, have strained the resources of the existing Internet infrastructure. This transformation of the network toward a packet- and cell-based infrastructure has introduced uncertainty into what has traditionally been a fairly deterministic network.

In addition to the issue of resource constraints, another challenge relates to the transport of bits and bytes over the backbone to provide differentiated classes of service to users. The exponential growth in the number of users and the volume of traffic adds another dimension to this problem. Class of service (CoS) and QoS issues must be addressed to in order to support the diverse requirements of the wide range of network users.

In sum, despite some initial challenges, MPLS will play an important role in the routing, switching, and forwarding of packets through the next-generation network in order to meet the service demands of the network users.