Despite the fact that there are extensive studies on Internet’s topology, it is still not very clear about the topological characteristics and their implication to some practical networking issues. Thus in this thesis research I study router-level networks of several Internet Service Providers (ISPs). By simulating the bandwidth constrained environ- ment, I identify amongst these networks a set of common topological characteristics, common behavior of carrying competing traffic-flows, and their inter-relationships. To investigate competing traffic-flows in particular, I discuss several bandwidth adjust- ment schemes and demonstrate the effectiveness of them in high as well as low network usage scenarios. I also present some comparison between AS networks against some topology models. With the current study, I am contributing a better understanding about the Internet’s topological characteristics and their practical implication to net- working practice, aiming to serve as one additional reference toward context-specific topology models of the Internet.