Visualizing Internet Topology Dynamics with Cyclops

1
Visualizing Internet Topology Dynamics with
Cyclops
Ricardo Oliveira, Ying-Ju Chi, Ioannis
Pefkianakis, Mohit Lad, Lixia Zhang
University of California, Los Angeles
Introduction

• Why visualize topology dynamics?
• To help observe the Internet topology evolution
  and understand the driving forces behind this
  evolution.
• To enable users and ISPs to make informed
  decisions regarding provider selection and
  connectivity adjustment.

• Cyclops Visualizes connectivity changes of a
  given AS
• Red indicates edges and nodes that disappeared
• Green indicates newer edges and nodes
• Stroke pattern differentiates ASs Tier1s (bold),
  transits (dotted) and stubs (solid)
• The transparency of a vertex/edge is proportional
  to the confidence level of the observed change
• Data Source
• RouteViews RIPE RIS, route servers and looking
  glasses

Cyclops Screenshot
Case Studies

• Case I Cogent Depeerings
• During April 2007, Cogent depeered with several
  European ISPs. The figure shows the connectivity
  changes seen by Cogent (AS 174) during the month
  of April 2007.

• Case II Correlating changes in space
• Cyclops allows one to view connectivity changes
  of any node in the graph.
• In the figure, AS 209 lost peerings with AS 6395
  and AS 8075.
• Expanding the view to see connectivity dynamics
  of AS 6395 and AS 8075 both ASs lost peering
  connections to other ASs during the same period,
  suggesting that the lost connectivity to AS209 is
  not an isolated event.

Case I Cogent depeerings in April 2007

• Case III Route leakage
• On July 6 2007 several sites, including Yahoo,
  were unreachable for about one hour
• The cause AS9318 leaked routes it should not
  advertise
• Cyclops shows AS9318 had a set of neighbors
  appeared and disappeared in the same day, a
  strong indication of a route leakage

Case II AS 209 link losses in April 2007 view
after expanding 209 neighbors' connectivity.

• Getting Cyclops
• Cyclops available as a Java applet
• Launch from http//irl.cs.ucla.edu/cyclops/
• Ongoing and Future Work
• Include activity bar in the interface to better
  locate large scale topology changes
• Show aggregated link change statistics per ASN
• Rank ASNs according to their connectivity changes.

Case III AS9318 route leakage on 7/6/07, causing
Yahoo outage.