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

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

3. 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

4. Cable ship...

5. …and the cable.

6. Global IP Backbone Network

7. 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

8. 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)

9. 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

10. 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

11. MPLS LSP Deployment

12. 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

13. Why Traffic Engineering?

14. MPLS Traffic Engineering

15. 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

16. 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

17. 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...

18. 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

19. 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

20. 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

21. Questions?