Experiences with Deploying a Global IP/MPLS Network

Experiences with Deploying a Global IP/MPLS Network

Thomas TelkampDirector Data Architecture and TechnologyGlobal Crossing Telecommunications, Inc.telkamp@gblx.net

China International SummitTechnology Convergence &

Next Generation Networks

September 25 - 26, 2001

Beijing, P.R. China

AgendaAgenda

•Global Crossing Network•IP Network Evolution and Philosophy•MPLS Deployment•IP VPNs•Multi-Service and DiffServ•New Features•Other Issues•Summary

Global Crossing HistoryGlobal Crossing History

•The First Independent Global Fiber Network Started operations in March 1997 First segment in service on May 26, 1998

•Expanding Network and Services by acquisitions: Frontier Telecommunications, Sept 1999 Racal Telecom, Nov 1999 Hutchison Global Crossing, Jan 2000 IXNET/IPC, June 2000

•Global Network 100,000 route mile, 27 countries, 200 major cities

Cable ship...Cable ship...

…and the cable.…and the cable.

Global IP Backbone NetworkGlobal IP Backbone Network

Global IP NetworkGlobal IP Network

•OC-48c/STM-16c (2.5Gbps) IP backbone Some 10Gbps segments operational (e.g.

Atlantic)•Multi-Vendor:

Cisco GSR 12000/12400 Juniper M20/M40/M160

•BGP and IS-IS routing protocols•Internet Access & Transit Services•IP VPN, Layer 3 and Layer 2•Global MPLS and DiffServ deployment

IP Network EvolutionIP Network Evolution

•Network technology and usage changes over time

•Roadmap US domestic backbone for Internet traffic MPLS deployment for Traffic Engineering Global extension of the network RFC2547 VPNs DiffServ deployment for multi-service Optimization for critical services (e.g. voice)

Network PhilosophyNetwork Philosophy•No bottlenecks in normal condition•Overprovisioning

with use of Traffic Engineering network can handle all traffic, even when the most critical links fails

•MPLS Traffic Engineering to prevent congestion•DiffServ to manage congestion

•Too complex and too many features will make the network unreliable/unstable

MPLS DeploymentMPLS Deployment

•Operational since 2Q 1999 Traffic Engineering IP TTL issues

•Worldwide MPLS mesh 1Q 2001•Currently over 6000 MPLS LSPs

•Support for RFC2547 VPNs MPLS/BGP technology

MPLS LSP DeploymentMPLS LSP Deployment

MPLS Deployment Experiences and ChallengesMPLS Deployment Experiences and Challenges

•Router vendor interoperability Cisco and Juniper New features...

•Requires seamless network Single AS Single IGP (no multiple areas/levels)

•NOC education and training•Network Management

Software to support Traffic Engineering

Why Traffic Engineering?Why Traffic Engineering?

MPLS Traffic EngineeringMPLS Traffic Engineering

IP VPNsIP VPNs

•RFC2547 VPN Based on existing MPLS and BGP

protocols

•Minimal impact on operations if already running a MPLS based Internet backbone

•Layer 2 variant under development

DiffServ DeploymentDiffServ Deployment

•Increase revenue by value-added services Best-Effort

• Internet Assured

• trading and non-interactive audio and video) Real-time

• voice

•Prefer ‘higher’ classes during congestion major failures guarantee delay and jitter

DiffServ ChallengesDiffServ Challenges

•How many classes? What are the targeted applications for each

class? Can end users distinguish between classes?

•How to implement these classes? Different queuing/scheduling mechanisms

• Strict Priority Queuing• WRR/WFQ• and combinations

Configuration and Monitoring issues...

New FeaturesNew Features

•MPLS Fast Reroute Provides SDH like restoration times for critical

services (e.g. voice and trading)

•Per-Class Traffic Engineering Avoid concentration of real-time traffic at any

link Set upper limit on bandwidth reservations per

class

•IGP tuning for better performance• IS-IS parameters and configuration

Other Issues...Other Issues...

•What about GMPLS? What are the benefits to the IP layer? What problems does it solve?

•Do we still need ATM? Cell based networks have different

characteristics than packet based networks CBR service for Circuit Emulation

•Should we build ‘Pure IP’ networks? There are alternatives to MPLS Traffic

Engineering and MPLS based VPNs

SummarySummary

•Evolve existing network or build new network based on applications and requirements: MPLS for Traffic Engineering DiffServ for service differentiation Advanced features for critical applications

•Don’t underestimate the operational aspects of new technology in the network

•Too complex and too many features will make the network unreliable and unstable

Questions?Questions?