Inter-domain router placement and traffic engineering

The Internet is organized as an interconnection of separate administrative domains called Autonomous Systems (AS). The Border Gateway Protocol (BGP) is the de facto standard for controlling the routing of traffic across different ASs. It supports scalable distribution of reachability and routing policy information among different ASs. In this paper, we study a network design problem which determines (1) the optimal placement of border router(s) within a domain and (2) the corresponding inter-and intra-domain traffic patterns within an AS. Practical constraints imposed by BGP and other standard shortest-path-based intra-domain routing protocols are considered. The problem is formulated as a variant of the uncapacitated network design problem (UNDP). While it is feasible to use a brute-force, integer-programming-based approach for tackling small instances of this problem, we have resorted to a dual-ascent approximation approach for mid/large-scale instances. The quality of the approximation approach is evaluated in terms of its computational efficiency and network cost sub-optimality. Sensitivity analysis w.r.t. various network/traffic parameters are also conducted. We then describe how one can apply our optimization results to better configure BGP as well as other intra-domain routing protocols. This serves as a first-step towards the auto-configuration of Internet routing protocols, BGP in particular, which is "well-known" for its tedious and error-prone configuration needs.published_or_final_versio

BGP ingress-to-egress route configuration in a capacity-constrained AS

The BGP ingress-to-egress route configuration problem is to find a set of paths in an ISP to carry the transit flows, such that the amount of network resources consumed is minimized without violating the bandwidth constraint on all network links. To solve the problem, we first formulate it using Integer Linear Programming (ILP). Due to the high complexity involved in ILP, a heuristic algorithm, called MPPF, is then proposed. MPPF is designed based on the idea that heavily-loaded destination prefixes should be given higher priority to select less expensive edge links and routes. Simulation results show that MPPF requires less network resources and edge link capacity than an alternative heuristic called BTF. © 2005 IEEE.published_or_final_versio

BGP ingress-to-egress route configuration in a capacity-constrained AS

The BGP ingress-to-egress route configuration problem is to find a set of paths in an ISP to carry the transit flows, such that the amount of network resources consumed is minimized without violating the bandwidth constraint on all network links. To solve the problem, we first formulate it using Integer Linear Programming (ILP). Due to the high complexity involved in ILP, a heuristic algorithm, called MPPF, is then proposed. MPPF is designed based on the idea that heavily-loaded destination prefixes should be given higher priority to select less expensive edge links and routes. Simulation results show that MPPF requires less network resources and edge link capacity than an alternative heuristic called BTF. © 2005 IEEE.published_or_final_versio