MPLS Fundamentals

Vaibhav Agarwal

Agenda

• Drivers Behind MPLS Adoption• What is MPLS• MPLS and OSI• Workflow of MPLS• Key concepts• Components of MPLS• Applications• MPLS VPN

Drivers behind MPLS Adoption

• Changing Telecom Landscape• Customer Requirements• Service Provider Requirements

Changing Telecom Landscape

Customer Requirements

Service Provider Requirements

The Barriers

The Solution

• MULTI-PROTOCOL LABEL SWITCHING - A mechanism that delivers the best of both worlds:

PRIVACY and QOS of Layer 2FLEXIBILITY and SCALABILITY of Layer 3

What is MPLS?

• MPLS is a packet-forwarding technology which uses labels to make data forwarding decisions.

• With MPLS, the Layer 3 header analysis is done just once (when the packet enters the MPLS domain)

• It is a Protocol Independent Technology.

MPLS and OSI

10

Physical

IP

ApplicationsTCP UDP

MPLS

ATM/PPP/Frame Relay/Ethernet

When a layer is added, no modification is necessary on the existing layers.

How does it work?

11

IP L1 IP L2 IP L3 IP IP

LSR LSRLER LER

IPRouting

IPRouting

LabelSwitching

LabelSwitching

Add label at the ingress LER

remove label at the egress LER

• Packet forwarding is done based on labels.• Labels are assigned when the packet enter the

network.• Labels allocated from a LOCAL POOL in the

router.• Labels are on top of the packet.• MPLS nodes forward packets/cells based on

the label value (not on the IP information).

MPLS Concepts

MPLS Components

MPLS Applications

• Virtual Private Networking (VPN)• Traffic Engineering (TE)• Quality of Service (QoS)• Any Transport over MPLS (AToM)

MPLS VPNs

• Private, connectionless IP VPNs• Outstanding scalability.• Customer IP addressing freedom.• Multiple QoS classes.• Simplified VPN Provisioning.• Support over any access or backbone

technology.

VPN “B”

VPN “B”VPN “A”

VPN “A”

MPLS VPN: Supporting Shared Services

Service ProviderMPLS - VPN NetworkInternet

PSTN

Shared Services for all VPNs

InternetGateway

VoIPGateway

ERP VideoServer

HostedContent

• IP Services move into Service Provider network and become sharable

Increases Enterprise outsourcing flexibility Creates New Service Provider revenue opportunities

Any Questions?