UKNOF 3

1. How to integrate 13 networks into one and live to tell the tale UKNOF 3 Mark Schleifer VP IP Engineering Mschleifer@cogentco.com Cogent Communications 1015 31st Street NW Washington DC 20007 USA www.cogentco.com

2. Our Network One of the World’s Largest All-Optical IP Network Inter-Continental Diverse

3. Our Milestones Cogent’s Success Story combines Organic Growth and Acquisition-based External Growth January 2004 France & Spain markets launch February 2002 COI listed on AMEX August 2004 Launches U.S. Layer 2 services April 2002 Offers Off-Net Internet service & colocation September 2004 Germany market launch November 2001 20th U.S. market complete August 1999 Cogent founded October 2004 Offer wholesale dial IP services July 2005 Cogent named largest Ethernet service provider in U.S. by Ovum-RHK November 2000 Backbone lit in initial 4 markets November 2002 Toronto market launch November 2004 Launches managed security service Milestones 1999 2000 2001 2002 2003 2004 2005 September 2001 Acquires assets of NetRail June 2005 Cogent raises $69 million in secondary offering April 2002 Acquires major U.S. assets of PSINet Acquisitions February 2003 Acquires Fiber Network Solutions January 2004 Acquires LambdaNet France & Spain February 2002 Acquires Allied Riser May 2003 Acquires assets of Applied Theory March 2004 Acquire fiber network & equipment in Germany out of former Carrier 1 assets April 2002 Acquires building access agreements from OnSite Access September 2002 Acquires major assets of FiberCity Networks August 2004 Acquires UFO September 2004 Acquires Global Access Since 2001, Cogent acquired the entire business or select assets of 13 companies. October 2004 Acquires Aleron Broadband December 2004 Acquires NTT/Verio dedicated access business in U.S.

4. Engineering Goals • Get Traffic on-net ASAP • Turn down acquired backbone • Turn down acquired Transit • Consolidate multiple POPs in a city • Consolidate Leased Circuits

5. Toolbox • Tunnels • MPLS-TE • UTI/L2TPv3 • BGP • Local-as • War Room

6. 2001 • 9/2001 – Netrail AS4006 • 34 devices/15 sites • New for Cogent – Off net TDM services • Tools Used • MPLS-TE Tunnels

7. 2002 • 4/2002 – PSInet AS174 • ~5000 off-net customers on ~250 devices • Frame Relay Backbone • New to Cogent – Frame Relay • Tools Used • MPLS-TE • UTI Tunnels • Local-as • Routers pretending to be Frame Switches

8. 2003 • 2/2003 -- Fiber Network Solutions (FNSI) – AS6259 • 400 Business customers on ~10 devices • Tools Used • L2TPv3 Tunnels • Local-as

9. 2004 • 1/2004 -- LambdaNet France/Spain • EU Backbone • New for Cogent - SDH Services • Splitting off from German Network • Linked IGP • AS Conversion • Tools Used • Local-as

10. 2004 (Cont) • 8/2004 – Unlimited Fiber Optics (UFO) – AS22099 • New for Cogent – Layer 2 Business • Required buildout of Native Ethernet Backbone • 9/2004 – Global Access (GATel) AS13129 • Tools Used • Local-as

11. 2004 (Cont) • 10/2004 – Aleron AS4200 • Tools Used • MPLS-TE Tunnels • Local-as • 11/2004 – Verio • ~2400 Customers • Tools Used • Local-as • War Room

12. The Rest • 2/2002 – OnSite Access • Primarily Building Access Agreements • 2/2002 – Allied Riser (ARC) • Primarily Building Access Agreements • Assets Very helpful with PSInet Migration • Each city an Island with own AS & IPs • ARIN work to consolidate records • 9/2002 – FiberCity Networks • Primarily Building Access Agreements

13. The Rest (Cont) • 5/2003 Applied Theory • Customers circuits • 4/2004 Carrier 1 • German Fiber Backbone

14. Q&A Questions?