Technological Understanding of MPLS and VPNs

2 days

Individuals that need to gain a technical understanding of the MPLS VPNs specifically Systems Engineers, Network Administrators, Network Consultants, Technical Architects, and Security Consultants.

Prerequisites: Firm understanding of Wide Area Networking protocols, TCP/IP, routing, and Local Area Networking.


This course reviews the concepts of MPLS switching and delivers a detailed coverage of the Multi-Protocol Label Switching from a standards approach. The course covers in detail the MPLS VPNs as per RFC2547bis.



  • The IP Routing Paradigm
  • Data Processing
  • Limitations of IP Routing
  • Enterprise vs. Service Providers
  • Enabling Internet Technologies
  • MPLS as a Solution
  • The concept of MPLS
  • Examples of Label Technology
  • Benefits of MPLS
  • Applications of MPLS

Concepts and Terminology

  • Definition of a Label
  • Definition of a Shim
  • Label Switch Router
  • Label Edge Router
  • Label Switch Path
  • Label Information Base
  • Forward Equivalence Class
  • Label Stacks
  • TLV
  • Label Distribution Protocol
  • Establishing an LSP
  • Traffic Flow Aggregation and Splitting
  • Popping and Attaching Labels

The Label

  • Shim Review
  • Layers and Labels
  • Frame Relay and ATM
  • Ethernet, Gig, and 10 Gig
  • OSPF, BGPv4, IGRP, and E-IGRP
  • Shims detailed
  • Encapsulation
  • Implementations


  • ICMP Overview
  • MPLS and ICMP
  • ICMP Messages
  • ICMP Structure
  • Examples of MPLS and ICMP

Signalling Protocols - Label Distribution Protocol

  • Architecture of LDP
  • LSP Establishment
  • Label Binding
  • Unsolicited vs. Ordered
  • Liberal vs. Conservative
  • LDP & TCP
  • Message Format
  • Encoding Detailed
  • Examples of Encoding

Signalling Protocols - Constraint-based Routed Label Distribution Protocol

  • Architecture of CR-LDP
  • Benefits of CR-LDP
  • Routing and TLVs
  • Node and Abstract Node
  • Pre-emption
  • Route Pinning
  • Resource Class
  • CR-LDP Formats
  • CR-LDP Messages
  • TLC Encoding
  • Messages with Examples

Signalling Protocols - Resource Reservation Protocol - TE

  • RSVP Overview
  • PATH and Messages
  • RSVP Header Format
  • RSVP Messages
  • TE Header
  • TE Messages
  • RSVP-TE LSP Setup Flow
  • New RSVP-TE Objects
  • New C-types
  • RSVP-TE Label Request & Label Objects
  • LSP Tunnel IP Session Object
  • ERO & RRO Objects
  • Path Additional Data Object


  • ATM Overview
  • Drivers for MPLS over ATM
  • Updated Terminology
  • ATM-MPLS Models
  • RFC 2684
  • Shims and Encoding
  • Implementations of MPLS and ATM
  • ATM Label Stack Encoding
  • Passing SHIM fields across ATM
  • VC Merge & Non-VC Merge ATM-LSRs
  • Communication from edge to edge LSRs

BGP 4 and MPLS

  • Overview of BGP
  • IBGP vs. MPLS
  • Extensions to BGPv4
  • MBGP
  • BGP-MPLS operation
  • Messages

Virtual Private Networks

  • A brief review of VPN
  • VPN Overlay & Peer Models
  • VPN Peer Model Key Technologies
  • Constrained Distribution of Routing
  • Communities
  • VPN-IP Address
  • BGP in PE, IGP within the Provider Network
  • MPLS as the forwarding Mechanism

MPLS QoS Support

  • IP QoS Overview
  • IntServ QoS Model
  • MPLS RSVP-TE Support of IntServ QoS
  • Diff-Serv QoS Model
  • MPLS Support of Diff-Serv


  • MPLS Analyzers
  • Internet Initiatives
  • Wrap up Q&A
Skills Taught: 
  • Explain MPLS and MPLS VPNs from a conceptual standpoint
  • Describe the architecture & components of MPLS VPNs
  • Compare and contrast the Label Distribution Protocols employed in MPLS and MPLS VPNs
  • Explain the use of BGP and modified BGP for MPLS VPNs
  • Describe how Quality of Service and traffic engineering are delivered using MPLS VPNs