Did you ever order something online from a distant retailer and then track the package as it makes strange and seemingly illogical stops all over the country?
That’s similar to the way IP routing on the Internet works. When an internet router receives an IP packet, that packet carries no information beyond a destination IP address. There is no instruction on how that packet should get to its destination or how it should be treated along the way.
Each router has to make an independent forwarding decision for each packet based solely on the packet’s network-layer header. Thus, every time a packet arrives at a router, the router has to “think through” where to send the packet next. The router does this by referring to complex routing tables.
The process is repeated at each hop along the route until the packet eventually reaches its destination. All of those hops and all of those individual routing decisions result in poor performance for time-sensitive applications like videoconferencing or voice over IP (VoIP).
What is MPLS
Multi-protocol label switching (MPLS), is a tried and true networking technology that has powered enterprise networks for over two decades. Unlike other network protocols that route traffic based on source and destination address, MPLS routes traffic based on predetermined “labels”.
Businesses use MPLS to connect remote branch offices that require access to data or applications that reside in the organization’s data center or company headquarters.
How MPLS works
With MPLS, the first time a packet enters the network, it’s assigned to a specific forwarding class of service (CoS)—also known as a forwarding equivalence class (FEC)–indicated by appending a short bit sequence (the label) to the packet. These classes are often indicative of the type of traffic they carry. For example, a business might label the classes real