2. How To Build a Redundant, Fault Tolerant, Load Balanced, Traffic Managed Wireless network a bella mia company

3. A Little Background Jeremy Kinsey “Known as Jer” to his friends. CEO and Co-Founder of Bella Mia, Inc. Been an ISP for 6 years Been a WISP for 2 + years

4. So you are a Wireless ISP But how do you make your system Redundant?

5. Some Assumptions You have at least 2 WPOPS (Wireless Points of Presence) You already have a redundant network, ie., are running BGP, have two providers, etc. You have a good understanding of Cisco Routers and various routing protocols.

6. Assuming you have all that, lets take a look at how things break down.

7. Lets Start at the WPOP 3 180 degree Sectors 3 runs of Heliax 4 radios Proxim COR’s Cisco 1600 Series Router UPS Switch

8. Where do the pieces fit? One Sector per side of tower One Radio per sector UPS, Radio, Switch, Router in enclosure at tower base. Router connected to T1 and NOC

9. The Big Picture Internet NOC Router Bandwidth Manager WPOP 1 WPOP 2 T1 Wireless PTP

10. So what do we have? Redundancy at the WPOP (3 separate radios & antennas) Redundancy in the entire system (multiple paths, traffic re-routed on the fly) Shared bandwidth (load balanced traffic, and bandwidth delivered where it is needed on demand)

11. Another Key Point! _ Imagine Zero Down Time Easily add to existing infrastructure Upgrade Remote Devices Replace Downed Gear Maintenanc e !

12. But does it Work? Well Let’s See it in Action!

13. Some Examples WPOP 1 Aggregate Traffic WPOP 2 Aggregate Traffic Traffic Flow over PTP between WPOP 1 & WPOP 2

14. What does it look like when a pipe goes down? 1 Pipe goes down, traffic automatically re-routed over backup link Pipe comes back up, PTP traffic will return to normal Your users never know what happened PTP under normal conditions PTP with 1 T1 Down

15. Where do you go from here?

16. Endless Expansion! Internet NOC Router Bandwidth Manager WPOP 1WPOP 2 T1T1 T1 Wireless PTP Wireless PTP to NOC WPOP 4 WPOP 3 Wireless PTP

17. So How Do I Do It? Now for the routing side of the “Keeping It Up”session Josh Easton, CTO Bella Mia, Inc. Routing protocols used and why

18. OSPF Open Shortest Path First Allows for redundancy Smarter routing of traffic

19. Brief intro to OSPF Every network link (T1, ethernet, etc.) has a cost When multiple paths are available, lowest cost path is chosen Costs can be manipulated to route your traffic ideally

20. How does OSPF fit in? Internet NOC Router Bandwidth Manager WPOP 1 WPOP 2 T1 Wireless PTP Cost = 64 Cost = 10

21. Why these costs? T1 has a default cost of 64 10Mbit ethernet’s default cost is 10 Traffic from WPOP1 to WPOP2 will take the wireless PTP link if it’s available, else it will use T1s Traffic from WPOP1 to Internet goes via the local T1, else via the wireless PTP link to WPOP2 and then via WPOP2’s T1

22. Sample Cisco router config Note: Need IP+ image to do OSPF on 1600 interface Ethernet0 ip address 10.0.0.1 255.255.255.0 ! Just an example ip address ip ospf message-digest key 1 md5 exit interface Serial0 ip address 10.0.1.1 255.255.255.0 ! Just an example ip address ip ospf message-digest key 1 md5 exit router ospf 100 redistribute connected subnets redistribute static subnets network 10.0.0.1 0.0.0.0 area 0 network 10.0.1.1 0.0.0.0 area 0 default-information originate always area 0 authentication message-digest ospf log-adjacency-changes exit

23. OSPF in a larger network Internet NOC Router Bandwidth Manager WPOP 1WPOP 2 T1 Wireless PTP Wireless PTP to NOC WPOP 4 WPOP 3 Wireless PTP Cost = 64 Cost = 10Cost = 45 Cost = 10

24. Why these costs? Cost from WPOP1 to WPOP3 is manually set at 45 Traffic from one WPOP to another WPOP will use the wireless backbone by default WPOP3 and WPOP4 use WPOP4’s link to the NOC to get on the Internet WPOP1 and WPOP2 use their T1s to get on the Internet If any link goes down, traffic will be routed around the damage

25. Questions?