MPLS or Multiprotocol Label Switching and leased lines are both used in Wide Area Network. However, one of the major differences between the two is that they work differently. The operation of this MPLS is not based on the data packets sent but the labels that come with them.
The decision to be made by the routers when data packets are sent is based on the information revealed by the labels that come with them. MPLS is also known as layer 2.5 protocol and doesn't only work for as a unified data-carrying service for circuit-based clients, but also for packet-switching clients. On the other hand, a leased line is a high-speed telecommunication line built to connect two sites.
A leased line offers a more secure connection compared to MPLS since it does not share its connectivity with other customers. Another difference is that MPLS is a newer technology compared to leased lines.
Both leased lines and MPLS provide WAN (Wide Area Network) connectivity. MPLS usually functions by being implemented as a full mesh, while a leased line functions by establishing a connection between two points. Actually, the full meaning of MPLS is Multiprotocol Label Switching.
It is known as a mechanism that carries data. In the MPLS network, you assign labels to data packets. MPLS permits the creation of end-to-end circuits by using any protocol across all transport medium types. The MPLS framework is a bit complex. It also depends on some data link technology like frame relay, synchronous optical networking.
A leased-line is referred to as a service contract between a provider and a customer. A consumer pays the provider most likely on a monthly basis after the provider must have provided asymmetric communication line that connects several locations. There is no telephone number involved, and lines are connected to themselves.