MPLS is the key element in the process of controlling traffic flow through a network to optimize resource deployment and network performance. Traffic engineering is vital as the current IGPs deploy shortest routes to promote traffic, which leads to network resources conservation, high-speed data forwarding between LSRs Label Switched Routers and reservation of bandwidth for varying QoS - Quality of Service requirements.
Numerous approaches to label distribution can be deployed depending upon the requirement of hardware that forms the MPLS network, and the administrative policies. The underlying principle though is that an LSP Label Switch Path is set up either in response to the requisition from the on-demand LSR or pre-emptively via LSRs network. At the MPLS network gateway, each packet is checked to determine the most suitable LSPs that are created for a variety of purposes such as to establish network-specific IP virtual private networks and to direct traffic along specific paths through the network. MPLS makes it convenient to create virtual links between the nodes to encapsulate the packets of data according to various network protocols.
MPLS providers aid the biggest drawback of present day internet i.e. the inability to manage traffic. Since all traffic receives best-effort service, there is no way to estimate priority or guarantee of QoS Quality of Service. Furthermore, route selection is based on the shortest path routing on the basis of additive link metrics. These approaches are however flawed as protocols again dont consider the characteristics of offered traffic and network capacity. This leads to erratic network congestion while alternate paths remain underutilized.
Such problems are the outcome of poor resource allocation, which is specifically addressed through MPLS.
MPLSs network layer scalability and integration of layer 2 switching and layer 3 routing not only addresses the internet traffic problems but increases network scalability, simplifies network service integration, provides integrated recovery, and simplifies network design, operation and management. MPLS providers believe that from service and cost perspective it allows to provide services not readily supported by conservative IP routing techniques. It is expected to improve price, performance of network routing and deliver higher flexibility in the delivery of new routing services, without changing the forwarding paradigm.
MPLS traffic engineering saves you from manually configuring the network devices to allocate explicit routes. Instead, the functionality delivers a full solution to traffic engineering a backbone and the automated signaling process. It accounts for link bandwidth and for the size of the traffic flow when determining explicit routes across the backbone.
