Creating realistic BGP models

Modeling the Internet infrastructure is a challenging en-deavor. Complex interactions between protocols, increas-ing traffic volumes and the irregular structure of the Inter-net lead to demanding requirements for the simulation de-veloper. These requirements include implementation detail, memory efficiency and scalability, among others. We intro-duce a simulation model of the Border Gateway Protocol that we call BGP++, which is built on the popular ns-2 sim-ulation environment. A novel development approach is pre-sented that incorporates the public domain routing software GNU Zebra in the simulator. Most of the original software functionality is retained, while the transition to the simula-tion environment required a manageable amount of effort. Moreover, the discussed design inherits much of the matu-rity of the original software, since the later is only mini-mally modified. We analyze BGP++ features and highlight its potential to provide significant aid in BGP research and modeling. 1