1. 1 UHG MPLS Experience June 14, 2005 Sorell Slaymaker Director Network Architecture & Technologies sorell_slaymaker@uhc.com

2. 2 Overview of United Health Group Diversified Health Care Company 41B in revenue 11B in acquisitions in 2004 6 Primary Divisions with 150 offices, primarily in the U.S. 42,000 employees - 5,000 in IT 4 primary and 11 secondary data centers 500 business applications, key applications are home grown Use technology as a competitive advantage Goal of IT infrastructure is to be reliable, efficient, cost effective In-sourced voice & data network with 70M/year savings with a 25% improvement in network availability and performance

3. 3 Why MPLS on WAN Any to Any Connectivity –Performance – Optimal routing of traffic – Avoid tandem routing through a hub –Lower Costs – FR & ATM w/ multiple PVCs, private line, and a CTI network. WAN transport costs reduced by 25% (12M to 9M - 48 sites getting less bandwidth, 29 getting more, & 70 staying the same) Convergence –QoS for key data applications that use to run on separate data networks –Voice – Migration to VoIP and IPT –One IP Network for all applications – Voice, data, video, remote storage, … Flexibility –Ability to scale – Add Bandwidth quickly over multiple layer 2 options –Traffic Engineering – Can tune how traffic routes across network

4. 4 Experienced only one outage at a single site during migration Had good back out plans Used underlying existing T1 & DS-3 circuits in most cases Continued to experience outages using IMA (sites requiring 3-9Mbps) UHG MPLS Migration Simulate all business unit applications on a lab-based MPLS network Document results Simulate all business unit applications on a lab-based MPLS network Document results Proof of Concept Phase 1 (completed) Phase 2 (in progress) Phase 2 (in progress) Phase 3 Phase 4 Cutover pilot sites to public MPLS service to ensure performance Finalize design Operationalize Cutover pilot sites to public MPLS service to ensure performance Finalize design Operationalize Pilot Cutover all current data WAN sites to the MPLS network Decommission the existing data WANs Cutover all current data WAN sites to the MPLS network Decommission the existing data WANs Roll-out Add 2 nd Carrier in an active/active config. To critical & large sites Tune QoS model Validate reporting (performance & billing) Add 2 nd Carrier in an active/active config. To critical & large sites Tune QoS model Validate reporting (performance & billing) Extension 3Q03 4Q03 2Q03 1Q03 1Q05 Phase 5 Scale VoIP New Acquisitions Conferencing VoIP New Acquisitions Conferencing 3Q05

5. 5 UHG MPLS Configuration 150 sites in the U.S. - 25 sites are large enough to require DS-3 access with VoIP and data center connectivity the primary requirements for bandwidth. Private IP VPN service for WAN – IPsec VPNs are used for external access for home users and 3 rd party connectivity. Encryption on our core WAN is not required and we wanted to avoid the overhead of IPsec. We own and manage the edge routers and use Netflow & Concord to monitor performance We defined our private IP addressing and AS numbers Use BGP for the CE to PE routing (internal network has a BGP core and OSPF at each site giving us scalability and control)

6. 6 UHG Challenges in Migrating to MPLS Training –MPLS – New technology –BGP – Virtual VPN services requires layer 3 – IP knowledge Different Carrier Approaches –Who defines AS & IP numbers –QoS Policies –Routing Policies in an active/active mode and asymmetric traffic Management –End to end measurements – Dropped packets, Latency, Jitter –QoS policies – Validating the right traffic is in the right queue

7. 7 UHG MPLS Best Practices QoS for a Site –60% RT – For Voice traffic –40% NRT – 60% - Critical Data – 30% - Normal Data – 10% - Best effort data ePVC not equal to port speed – Having the ability to burst Customer should design IP address & AS numbers, not carrier Invest in performance monitoring tools – We chose Concord & Netflow Meet with provider monthly to review availability, performance, and billing Adjust application timers to handle a 60 second reroute – IPagent, Citrix, Documentation is key – See Appendix 1

8. 8 UHG MPLS Futures Growth – OC-3 & Gig Ethernet to support 25%/year business growth VoIP growth - centralized call center & audio conferencing IPT conversion – UHG will be 90% IPT by end of 2006 Efficiencies ML-PPP – Replace ATM & IMA (Cell tax and stability) POS & GE – Replace ATM & FR on head end pipes Convergence Local & Off-net LD voice – A remote site will only have data connectivity External Connectivity Use MPLS for external network connections to share head end access while keeping the layer 3 networks separate.

9. 9 Conclusion Convergence and 1 network, an IP network, is where we are going and MPLS on the WAN is our chosen technology to get there Negotiating price along with service levels with carrier(s) of choice enable a cost effective & reliable solution Converting existing circuits to MPLS is fairly straight forward. Ordering new local access for new circuits has all the local access provisioning challenges. MPLS is mature from a platform perspective, but expect a lot of new services to be added in the next 2 years with local and off-net voice a key one. Training and staffing need to be addressed up front. Having engineers who are accountable for specific sites and then one who owns entire WAN has worked well. WAN Bandwidth demand has doubled in 2 years due to VoIP and growth of the company. Moving to MPLS has enabled us to keep up with demand while optimizing costs.

10. 10 Appendix 1 – Example Site Documentation

11. 11 Appendix 2 – QoS Measurements IP Protocol based Quality of Service (QoS) Application group based Class of Service (CoS) Both IP protocol based as well as application group classification can be applied to setup MPLS label switched paths (LSP). This provides the flexibility to provide both qualitative as well as quantitative service levels