2. Company and Product Overview

3. Company Overview Mission Provide core routing technologies and solutions for next generation carrier networks Founded 1996 Headquarters N. Billerica, MA First Product ShippedQ4 1999 Existing Customer Commitments$45M+ Employees360+ Awards Mission Provide core routing technologies and solutions for next generation carrier networks Founded 1996 Headquarters N. Billerica, MA First Product ShippedQ4 1999 Existing Customer Commitments$45M+ Employees360+ Awards

4. Explosive Demand for Data Services Peak-Hour Internet Bandwidth Demand Source: Pioneer Consulting LLC 120% CAGR (terabits per second)

5. Worldwide Carrier Router Market Source: Ryan Hankin and Kent 75% CAGR Core Router Market (in millions)

6. New Router Solutions are Required to Address the Bottleneck in the Core CARRIER OPTICAL TRANSPORT DWDM and OPTICAL SWITCHES Mismatch between Transmission Speeds and Capacity Existing Carrier Equipment SONET VoIP Gateways Cable Modem Aggregation Gigabit Ethernet Digital Subscriber Line Aggregation Gigabit Routers ATM DWDM and OPTICAL SWITCHES SONET VoIP Gateways Cable Modem Aggregation Gigabit Ethernet Digital Subscriber Line Aggregation Gigabit Routers ATM Existing Carrier Equipment Mismatch between Transmission Speeds and Capacity

7. OC-3 OC-48 OC-12 Limitations of Existing Routers Carrier Optical Transport Router Deployment Over Time OC-12 OC-48 OC-192 Transport Evolution Over Time EDGE CORE SONET and DWDM DWDM and OPTICAL SWITCHES SONET

8. A Single POP Backbone Today’s model of Intra-POP router clusters is insufficient Clustering Not a Solution  70% of router capacity is lost by clustering  Inefficient use of dedicated bandwidth  Significant network management problems  70% of router capacity is lost by clustering  Inefficient use of dedicated bandwidth  Significant network management problems

9. Avici’s TSR simplifies the POP The Solution

10. The Next Generation Carrier Network CARRIER OPTICAL TRANSPORT Existing Carrier Equipment SONET VoIP Gateways Cable Modem Aggregation Gigabit Ethernet Digital Subscriber Line Aggregation Gigabit Routers ATM SONET VoIP Gateways Cable Modem Aggregation Gigabit Ethernet Digital Subscriber Line Aggregation Gigabit Routers ATM Existing Carrier Equipment DWDM and OPTICAL SWITCHES AVICI TSR Avici Composite Links

11.  Carrier Class Reliability  ISP to Backbone Scaling –Very cost effective at small configurations –Extremely cost effective at large configurations  Composite Links  Dynamic Provisioning The Avici TSR - Superior Technology

12. Velociti™ Switch Fabric  Toroidal direct connect fabric  Scales to 560 active modules  Each element adds switching & forwarding capacity –Generation 1 - 60 Gbps –Generation 2 - 240 Gbps  Each module connects to 6 other modules  Path diversity –Resilient –Non-blocking  Toroidal direct connect fabric  Scales to 560 active modules  Each element adds switching & forwarding capacity –Generation 1 - 60 Gbps –Generation 2 - 240 Gbps  Each module connects to 6 other modules  Path diversity –Resilient –Non-blocking

13. Module I/O Architecture O/E Conversion SONET Termination Packet QoS Multicast Expander & Packet Scheduler Forwarding Engine Control Processor FE Interface PPP/MPLS Processing E/O Conversion SONET Termination PPP/MPLS Processing Switch Fabric BACKPLANE O/E Conversion Packet Memory 64 MB

14. PCMCIA PowerPC Processor Console Fast Ethernet HDD Server Memory 320Mb OSPFBGP4IS-IS MBGPPIMMSDP RSVPCLI SNMP FTP Control Processor FE Interface Software & System Architecture SONET Termination Packet QoS Multicast Expander & Packet Scheduler Forwarding Engine Control Processor FE Interface PPP/MPLS Processing E/O Conversion SONET Termination PPP/MPLS Processing Switch Fabric O/E Conversion SONET Termination Packet QoS Multicast Expander & Packet Scheduler Forwarding Engine Control Processor FE Interface PPP/MPLS Processing E/O Conversion SONET Termination PPP/MPLS Processing Switch Fabric O/E Conversion SONET Termination Packet QoS Multicast Expander & Packet Scheduler Forwarding Engine Control Processor FE Interface PPP/MPLS Processing E/O Conversion SONET Termination PPP/MPLS Processing Switch Fabric O/E Conversion Bay & Environment Controller Routing and Configuration tasks Forwarding and Fabric Routing tasks PCMCIA PowerPC Processor Console Fast Ethernet SSD Server Memory 320Mb OSPFBGP4IS-IS MBGPPIMMSDP RSVPCLI SNMP FTP Control Processor FE Interface SONET Termination Packet QoS Multicast Expander & Packet Scheduler Forwarding Engine Control Processor Server Interconnect PPP/MPLS Processing E/O Conversion SONET Termination PPP/MPLS Processing Switch Fabric O/E Conversion Packet Memory 64 Mb Module Control Software