Mattia Rossi

Securing BGP — A Literature Survey

The Border Gateway Protocol (BGP) is the Internets inter-domain routing protocol. One of the major concerns related to BGP is its lack of effective security measures, and as a result the routing infrastructure of the Internet is vulnerable to various forms of attack. This paper examines the Internets routing architecture and the design of BGP in particular, and surveys the work to date on securing BGP. To date no proposal has been seen as offering a combination of adequate security functions, suitable performance overheads and deployable support infrastructure. Some open questions on the next steps in the study of BGP security are posed.

A Technique for Reducing BGP Update Announcements through Path Exploration Damping

This paper defines and evaluates Path Exploration Damping (PED) - a router-level mechanism for reducing the volume of propagation of likely transient update messages within a BGP network and decreasing average time to restore reachability compared to current BGP Update damping practices. PED selectively delays and suppresses the propagation of BGP updates that either lengthen an existing AS Path or vary an existing AS Path without shortening its length. We show how PED impacts on convergence time compared to currently deployed mechanisms like Route Flap Damping (RFD), Minimum Route Advertisement Interval (MRAI) and Withdrawal Rate Limiting (WRATE). We replay Internet BGP update traffic captured at two Autonomous Systems to observe that a PED-enabled BGP speaker can reduce the total number of BGP announcements by up to 32% and reduce Path Exploration by 77% compared to conventional use of MRAI. We also describe how PED can be incrementally deployed in the Internet, as it interacts well with prevailing MRAI deployment, and enables restoration of reachability more quickly than MRAI.

TCP/IP over IEEE 802.11b WLAN: the Challenge of Harnessing Known-Corrupt Data

The two transport protocols DCCP and UDP-Lite can make use of data that are known to be erroneous, provided that the link layer hands over such data. A similar functionality has been suggested for TCP. In order to investigate the potential of these mechanisms in WiFi networks, we carried out a measurement study where we examined how often information about corrupt data reaches the transport layer when the corruption control at the link layer is disabled. Our results suggest that this may be a rare occurrence in certain scenarios.

Inferring the time-zones of prefixes and autonomous systems by monitoring game server discovery traffic

Geolocation of IP addresses is used for determining authenticity of webpages, delivering specific country or location related content and advertisements, or to add security for online transactions. Although IP geolocation databases exist, it is sometimes useful to validate their entries or create new, independent databases using independent sources of information. We propose and demonstrate a method whereby collecting and analyzing online game server discovery traffic over short periods of time can allow us to detect in which timezone a certain prefix or AS is located. Our method provides very good estimates of various AS timezones which we verify using publicly available IP geolocation databases.