MPLS intro from cicso
Multiprotocol Label Switching Overview
This chapter describes the Multiprotocol Label Switching (MPLS) distribution protocol. MPLS is a high-performance packet forwarding technology that integrates the performance and traffic management capabilities of data link layer (Layer 2) switching with the scalability, flexibility, and performance of network-layer (Layer 3) routing. It enables service providers to meet challenges brought about by explosive growth and provides the opportunity for differentiated services without necessitating the sacrifice of existing infrastructure.
The MPLS architecture is remarkable for its flexibility:
•
Data can be transferred over any combination of Layer 2 technologies
•
Support is offered for all Layer 3 protocols
•
Scaling is possible well beyond anything offered in today’s networks.
Specifically, MPLS can efficiently enable the delivery of IP services over an ATM switched network.
It supports the creation of different routes between a source and a destination on a purely router-based
Internet backbone. Service providers who use MPLS can save money and increase revenue and productivity. Procedures for configuring MPLS are provided in the “Configuring Multiprotocol Label Switching” chapter later in this publication.
Note
Label switching on a router requires that Cisco Express Forwarding (CEF) be enabled on that router.
Refer to the CEF feature documentation for configuration information. For more information on enabling CEF, see the “Configuring Cisco Express Forwarding” chapter in this publication.
This chapter describes MPLS. It contains the following sections:
•
MPLS/Tag Switching Terminology
•
MPLS Commands and Saved Configurations
•
MPLS/Tag Switching CLI Command Summary
•
Benefits
•
Label Switching Functions
•
Distribution of Label Bindings
•
MPLS and Routing
•
MPLS Traffic Engineering
•
MPLS Virtual Private Networks
Cisco IOS Switching
This chapter describes the Multiprotocol Label Switching (MPLS) distribution protocol. MPLS is a high-performance packet forwarding technology that integrates the performance and traffic management capabilities of data link layer (Layer 2) switching with the scalability, flexibility, and performance of network-layer (Layer 3) routing. It enables service providers to meet challenges brought about by explosive growth and provides the opportunity for differentiated services without necessitating the sacrifice of existing infrastructure.
The MPLS architecture is remarkable for its flexibility:
•
Data can be transferred over any combination of Layer 2 technologies
•
Support is offered for all Layer 3 protocols
•
Scaling is possible well beyond anything offered in today’s networks.
Specifically, MPLS can efficiently enable the delivery of IP services over an ATM switched network.
It supports the creation of different routes between a source and a destination on a purely router-based
Internet backbone. Service providers who use MPLS can save money and increase revenue and productivity. Procedures for configuring MPLS are provided in the “Configuring Multiprotocol Label Switching” chapter later in this publication.
Note
Label switching on a router requires that Cisco Express Forwarding (CEF) be enabled on that router.
Refer to the CEF feature documentation for configuration information. For more information on enabling CEF, see the “Configuring Cisco Express Forwarding” chapter in this publication.
This chapter describes MPLS. It contains the following sections:
•
MPLS/Tag Switching Terminology
•
MPLS Commands and Saved Configurations
•
MPLS/Tag Switching CLI Command Summary
•
Benefits
•
Label Switching Functions
•
Distribution of Label Bindings
•
MPLS and Routing
•
MPLS Traffic Engineering
•
MPLS Virtual Private Networks
Cisco IOS Switching