MPLS VPN Network 101: Your Guide To Understanding The Complete Technique

MPLS VPN is one of the most efficient VPN infrastructures that allows the usage of multiple protocol switching techniques to provide its services. It primarily consists of a number of sites that are interconnected to the provider's core network.

In MPLS VPN, customer edge devices are attached to provider edge devices for the smooth flow of data packets. It allows the advancement of data packets in the network at the switching level rather than at routing level.

MPLS VPN also allows the integration of networks located in multiple geographic locations by using private and exclusive routing protocols. Therefore, businesses that are looking to adopt cloud computing in their networks, MPLS becomes a perfect way to connect with the platforms.

In this article, everything one needs to know about MPLS, beginning from its history to its advantages, has been explained for a better understanding. Read on to know more.

MPLS VPN: The History

MPLS was primarily created to act as an efficient and effective alternative to traditional IP routing techniques. Due to the excessive time consumption and regular inspection of the routing table required in those techniques, there was no smooth functioning of the network.

Moreover, the traditional techniques many times resulted in performance failure when the data was big. Therefore, the MPLS network was created to ensure smooth determination of packet routes and their identification.

In addition, the constant improvement of the MPLS network has also been an essential part in increasing its flexibility, security, and engineering benefits.

MPLS VPN: The Working

In a layman’s language, one can think of MPLS, like mailing a packet. For developing and operating connections, networks need to look inside every data packet of all the routers to check if the network is functioning smoothly and where the data packet is forwarded. It is similar to having a look inside any shipment at different post offices along the way to find out where the package is headed to.

An ingress router that contains MPLS network will label data packets when they enter the network (post office) so that the routers (mail workers) would know exactly where the data packets are going without having to open and check the packages again and again.

MPLS VPN: The Architecture

The complete MPLS architecture is split into two different modules, the control module, and the forwarding module. Each of these modules is designed to create a structured network environment, eliminating performance failure. The modules are further divided into sub-components that each control specific functionality of the network; they include:

• The Label: It is a form of an identification process that holds all of the information collected for the MPLS routers. The identifier allows proper determination of routes in which data packets can be forwarded.
• Experimental: Experimental bits are used in the network for improving the Quality of Service (QoS). They allow the network to set the priority on which labels to be forwarded and how they should be marked.
• Bottom-of-Stack: The Bottom-of-Stack informs the MPLS Router if the journey of the labels it at its last leg and that there are no more labels to be checked, forwarded, or concerned with. Once this happens, it usually means the router is an egress router.
• Time-To-Live: The Time-To-Live options identify the number of hops the packet is allowed to make before the router discards it from the network.

MPLS VPN: The Benefits

Due to its increased efficiency and modern structure, the MPLS VPN network offers several new control features for service providers. The benefits of MPLS VPN have certainly been noticed by many organizations that use them, as this technology is widely adopted within telecom networks.

• Minimal Cost

MPLS is a Layer 2.5 technology. It not only permits the sharing of network resources but also allows private routing of valuable consumer data.

It has many operational and low-cost advantages that any Layer 3 public Internet has. Moreover, in MPLS, the users also get additional security and other efficiencies that make it the best routing method for large scale deployment. It is an IP-based but protocol-agnostic technique; therefore, is much more private than other network services.

• Quality of Service Attributes

One of the most talked-about benefits of MPLS VPN network is its ability to assign (Quality of Service) QoS features to oncoming traffic. Because MPLS networks perform with a system of different labels, customers can quickly determine the prioritization levels associated with them.

Due to the ability of MPLS to manage and control QoS, customers can now subscribe to different levels of bandwidth or sizes of ports, and get an ability to determine if there is congestion on their network link.

• Higher Scalability

MPLS combines many qualities of physical “nailed up” circuits which were difficult and costly to scale. With its new cost-effective but relatively unpredictable nature of pure IP routing, it increases the scalability of the router.

Moreover, when it comes to the scalability of complicated and large networks, MPLS allows one to automatically configure the network and set up of tunnels or label-switched paths.

Also, another benefit of the MPLS is its protocol-agnostic nature. Different types of network traffic can be carried out via MPLS routing without any regard to the type of traffic.

• Traffic Routing

MPLS works by imposing different labels on the data packets as they leave a customer’s network and enter the network. Therefore, rather than looking up the IP header information to direct the packets to their desired location, network elements read the MPLS label provided and whisk the packet along its pre-determined path.

Some other benefits of Multi-Protocol Label Switching include higher reliability and improved predictability of traffic moving within the network. Because the Label Switched Paths (LSPs) are always pre-determined, the packets only travel in the paths they are assigned to.