Experiences with Deploying a Global IP/MPLS Network China International Summit Technology Convergence & Next Generation Networks September 25 - 26, 2001 Beijing, P.R. China Experiences with Deploying a Global IP/MPLS Network Thomas Telkamp Director Data Architecture and Technology Global Crossing Telecommunications, Inc. telkamp@gblx.net

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

Global 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...

…and the cable.

Global IP Backbone Network

Global IP Network OC-48c/STM-16c (2.5Gbps) IP backbone Multi-Vendor: 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 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 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 Deployment Operational since 2Q 1999 Worldwide MPLS mesh 1Q 2001 Traffic Engineering IP TTL issues Worldwide MPLS mesh 1Q 2001 Currently over 6000 MPLS LSPs Support for RFC2547 VPNs MPLS/BGP technology

MPLS LSP Deployment

MPLS 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?

MPLS Traffic Engineering

IP 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 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 Challenges How many classes? How to implement these 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 Features MPLS Fast Reroute Per-Class Traffic Engineering 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... What about GMPLS? Do we still need ATM? 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

Summary 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?