Summary: Network Formation and Routing by Strategic Agents using
and Gordon Wilfong2
Department of Computer Science, Rensselaer Polytechnic Institute, Troy, NY.
Bell Labs, Murray Hill, NJ.
Abstract. The Internet consists of various independent entities that range from small residential
customers up to large backbone networks. The global network formation of the Internet is a
result of the independent actions of these entities trying to achieve their individual connectivity
needs balanced against their business goals. For example, customers accept contracts with ISPs to
connect them to the Internet while ISPs and larger Autonomous Systems (ASes) make contracts
called Service Level Agreements (SLAs) between each other to transit one another's traffic. ASes
also try to control the routing of traffic to and from their networks in order to achieve efficient
use of their infrastructure and to attempt to meet some level of quality of service globally.
We introduce a game theoretic model in order to gain understanding of this interplay between
network formation and routing. Strategies for the players in the game allow them to make contracts
with one another to forward traffic, and to re-route traffic that is currently routed through them.
This model extends earlier work of  that only considered the network formation aspect of the