We often talk about the importance and the value of the Sprint MPLS network, but we realized that rarely do we talk much about the mechanics of that network.
Of course, there are people who just like to get in the car and drive, without much thought about all the parts and processes involved from the turn of the key to the arrival at their destination. And then there are people who just love to open the hood and admire the engine. We thought it would be worthwhile to talk a little bit about what’s under the MPLS hood.
MPLS, as hood-lifters probably already know, is acronym-speak for Multiprotocol Label Switching. In a traditional IP network, packets - small pieces of data - are routed by a destination IP address. MPLS provides a way to map IP addresses to simple, fixed-length labels inserted at the front of each packet. This labeling system (the Label Switching part of MPLS) speeds the delivery of the packets by specifying the path the packets take. The data moves faster because the router no longer has to examine each packet and look up routing tables to see where the packets need to go next.
In essence, MPLS represents a refining of what ATM and Frame Relay networks set out to accomplish in the past. For example, MPLS can operate with variable length packets, while ATM is designed to carry 53-byte cells. In an ATM network, packets have to be segmented, transported, and then reassembled, which adds complexity and time. Sticking a label at the front of each packet is a much simpler and faster approach to moving data.
With an MPLS network you also can combine different types of data onto one network. MPLS interfaces to existing routing and switching protocols (the Multiprotocol part of MPLS), such as IP, ATM, and Frame Relay and Ethernet frames. This enables MPLS to run internet access, different data applications, and voice applications such as VoIP and SIP Trunking, at the same time over the same network, reducing the cost and resources required to manage disparate networks.
To process the different types of data, an MPLS network uses Classes of Service (CoS). CoS ensures Quality of Service (QoS) by assigning profiles to different applications. For example, for voice and video applications, the speed at which a packet is delivered is much more critical than that of email. Thus voice and other business-critical applications receive a higher CoS, giving them transport priority on the MPLS network.
The bottom line is that MPLS streamlines network traffic, particularly for latency-sensitive applications such as voice and video, and makes the traffic and the network easier to manage. In Sprint’s case, the result is a network that is incredibly flexible, super-fast, and easily able to handle network segmentation and quality of service priorities.
In a future post, we’ll look at the services made possible by the MPLS network foundation.
