MPLS (Multi Protocol Label Switching) technology is increasingly become popular globally and many older and newer networks have migrated to this technology. MPLS is a packet switched network. In MPLS technology, a label is added to each data packet. The forwarding and routing of this packet is based on this label and eliminates the need to examine the packet. In the traditional OSI model data link layer technology such as Frame Relay, Ethernet, ATM etc, multiple layer 2 networks are needed to handle different types of traffic. MPLS eliminates this need and an end to end circuit can be created using any type of transport medium with any protocol. This makes it very flexible and secure.
The cost of MPLS connectivity has been steadily decreasing and this has led to an exponential growth in bandwidth demand. Businesses that could only afford single low bandwidth connection, can now increase bandwidth, get a secondary connection or larger throughput for the same cost.
The growth and dependence on MPLS as a secure mode of transport, has brought dependability to the forefront of concerns. In this context, dependence on a single MPLS connection is saddled with the danger that if the connection fails the WAN is unavailable. Thus, MPLS redundancy should be a primary consideration for any network admin. MPLS redundancy can be imparted to a network by the addition of a second MPLS connection. This connection can be in the standby mode and can be set up so that when the primary MPLS line fails, this takes over. While this is a solution, it is not the most effective one.
Dynamic MPLS redundancy can be achieved through the use of existing market technology that aggregates two or more connections. This technology is referred to using different terminology and link load balancing, link aggregation etc are a couple of these. This technology for MPLS redundancy allows simultaneous use of both links. The devices dynamically balance the load and should one fail, all traffic fails over the line that is up. This is an install and forget technology, that relieves the IT admin staff of the responsibility of fighting WAN failure.
In addition to the basic functionality described above, this technology is also link type and provider agnostic. Thus, instead of a second MPLS line, a cheaper DSL or cable line could be utilized for MPLS redundancy. There are businesses that utilize built-in QoS functionality to direct production traffic on the MPLS line while all non production traffic is directed over the secondary connection. This gives admins the flexibility to have a mixed network.