This document provides an overview of MPLS (Multiprotocol Label Switching) including: - MPLS uses labels instead of IP addresses to forward packets for benefits like decreased routing overhead and support for non-IP protocols. - Key MPLS terminology includes label-switched routers that forward packets based on labels, edge routers that impose/remove labels, and label switched paths that define the path through the network. - The MPLS control plane establishes label switched paths and the data plane uses forwarding based on pre-established labels for faster switching compared to IP routing.

1. MPLS( Multiprotocol Label Switching)
KHNOG
30 November, 2015

2. Agenda
• Traditional IP Routing
• MPLS Introduction
• MPLS Features
• MPLS Benefits
• MPLS Terminology
• MPLS: Control Plane
• MPLS Data Plane
• Forwarding Structures
• MPLS Example
• Question and Answer

3. What is MPLS?
• It’s all about the Labels
• Use the best of both words
- Layer 2
- Layer 3
• Traditional IP Routing: The traditional IP
Routing where the packet forwarding discussion
are based on the IP address.

5. MPLS Features
• MPLS forwarding based on the MPLS label.

6. MPLS Benefits
In modern routers, MPLS label switching is not much
faster than IP routing, but MPLS is not used just
because of its switching performance.
There are several other benefits to MPLS:
• MPLS decreases the forwarding overhead on the
core routers.
• MPLS supports the forwarding of non-IP protocols,
because MPLS technologies are
applicable to any network layer protocol.

7. • MPLS supports multiple useful applications:
- Unicast and multicast IP routing
- VPN
- TE
- QoS
- Any Transport over MPLS (AToM)
MPLS is very useful in service provider (and large
enterprise) networks because it enhances
BGP routing and provides different services and
applications, such as Layer 2 and 3 VPNs,
QoS, and TE.

8. MPLS Terminology
• LSRs forward packets based on label and swap labels:
- The last LSR in the path also removes the label
and forward the IP packets as normal IP Routing

9. • Edge LSR:
- labels IP packet (impose label) and forwards them
into the MPLS domain
- Forwards IP packets out of the MPLS domain
• A sequence of labels to reach a destination is called an LSP
In an MPLS domain, there are two types of routes:
• Label-Switched Router (LSR): A device that forward
packets that are primarily based on labels
• Edge LSR: A device that primarily labels packets or
forwards IP packets out of an MPLS domain.

10. MPLS Control Plane

11. MPLS Data Plane

12. MPLS Forwarding Structures

13. MPLS Architecture Example

14. MPLS Packet Flow Basic Example