MPLS

Data Sheet

Cisco IOS Software and
Multiprotocol
Label Switching

The Challenges: The explosive growth of the Internet presents a serious challenge to service providers and equipment suppliers in terms of tremendous increases in traffic and the number of users. The demand for creating differentiated IP services and getting these new value-added services to market quickly is also increasing. Other challenges include additional costs of mapping IP over Layer 2 networks as well as difficulties in identifying better network utilization and fault handling. There is also a constant need to adapt to individual services in order to generate increased revenue streams.

The Solution: Cisco IOS® Multiprotocol Label Switching (MPLS) fuses the intelligence of routing with the performance of switching and provides significant benefits to networks with a pure IP architecture, as well as those with IP and ATM, or a mix of other Layer 2 technologies. MPLS technology is key to scalable virtual private networks (VPNs), end-to-end quality of service (QoS), enabling efficient utilization of existing networks to meet future growth and rapid fault correction of link and node failure. The technology also helps deliver highly scalable, differentiated end-to-end IP services with simpler configuration, management, and provisioning for both Internet providers and subscribers.

The MPLS standard, published by the Internet Engineering Task Force (IETF), evolved from the Cisco Tag Switching implementation. Cisco leadership and experience in the Tag Switching and MPLS arena translates into a feature-rich implementation and a robust, proven platform for service-provider and business networks.

MPLS Technology

Based on label swapping, a single forwarding mechanism provides opportunities for new control paradigms and applications. MPLS Label Forwarding is performed with a label lookup for an incoming label, which is then swapped with the outgoing label and finally sent to the next hop. Labels are imposed on the packets only once at the edge of the MPLS network and removed at the other end. These labels are assigned to packets based on groupings or forwarding equivalence classes (FECs). Packets belonging to the same FEC get similar treatment. The label is added between the Layer 2 and the Layer 3 header (in a packet environment) or in the virtual path identifier/virtual channel identifier (VPI/VCI) field (in ATM networks). The core network merely reads labels, applies appropriate services, and forwards packets based on the labels. This MPLS lookup and forwarding scheme offers the ability to explicitly control routing based on destination and source addresses, allowing easier introduction of new IP services.

Applications

Businesses rely on Cisco IOS Software for the delivery of the most complete MPLS feature set. The most common applications of Cisco IOS Software MPLS follow:

Traffic engineering is enabled through MPLS mechanisms that allow traffic to be directed through a specific path, which may not necessarily be the least-expensive path. Network managers can implement policies to ensure optimal traffic distribution and improve overall network utilization.

Guaranteed bandwidth is a value-added enhancement to traditional traffic-engineering mechanisms. MPLS lets service providers deliver guaranteed pipes and bandwidth allocations. Guaranteed bandwidth also allows bookkeeping of quality-of-service (QoS) resources to traffic engineer both premium and best-effort traffic such as voice and data.

Fast reroute (FRR) allows extremely quick recovery if a node or link fails. Such fast recovery prevents end-user applications from timing out and also prevents loss of data.

MPLS VPNs greatly simplify service deployment compared to traditional IP VPNs. As the number of routes and customers increases, MPLS VPNs easily scale, while providing the same level of privacy as Layer 2 technologies. In addition, they can transport nonunique IP addresses across a public domain.

MPLS class-of-service (CoS) capability ensures that important traffic is given the appropriate priority over the network and that latency requirements are met. IP QoS mechanisms can be seamlessly implemented in an MPLS environment.

Cisco IOS Software MPLS: Key Features and Benefits

Protocol Support

Platform Support

All Cisco IOS Software Release 12.1 versions and later include MPLS features.

For Additional Information

Additional information about the Cisco IOS MPLS technology can be found at http://www.cisco.com/go/mpls/ or by contacting your local Cisco representative.