Network Probe Daemon

  Focusing First on Normal
	 Traceroutes
    Flapping AS pathways 
 

• Flapping AS pathway Diagram

• Flapping can occur in a Dominate or a Shared pathway

• Flapping within a day

  (Flapping is over all AS pathways between all 45 NPD sites.)

• Flapping over 24 hours

  from beast.merit.edu to weeble.lut.ack.uk

• One Example of Flap Oscilation

• Why does Flapping Occur?

  • Equal BGP pathways - new Cisco features (Curtis Villamizar)

  • Route Fluctuations.

  • Routing Policy Change or Network Maintenace.

  • Other reasons?

• More research needed to determine the reasons for flap

Dun Liu, Bill Norton, Susan Hares

Merit Network