| Popis: |
Internet service providers (ISPs) have a variety of quality attributes that determine their attractiveness for data transmission, ranging from quality-of-service metrics such as jitter to security properties such as the presence of DDoS defense systems. ISPs improve these attributes in line with their profit objective, i.e., up to the level that maximizes revenue from attracted traffic while minimizing attribute-related cost, all in the context of alternative offers by competing ISPs. In today's Internet, this quality competition mostly takes place between ISPs that are next-hop options for a given destination. In contrast, emerging path-aware networks enable end-points to select entire inter-domain forwarding paths, and thus intensify ISP competition. In this paper, we analyze how path-aware networking changes the competition dynamics in the Internet, and how path quality and ISP profits are affected as a result. To that end, we develop a game-theoretic model in which ISPs (i) affect path quality via multiple attributes that entail costs, (ii) constitute paths together with other selfish ISPs, and (iii) are in competition with alternative paths when attracting traffic. The model enables an extensive theoretical analysis, surprisingly showing that end-point path selection can have both positive and negative effects on path quality and ISP profits, depending on the network topology and the cost structure of ISPs. However, a large-scale simulation, which draws on real-world data to set model parameters, shows that the positive effects will likely prevail in practice: Compared to a single-path scenario, the prevalence of quality attributes increases by at least 50%, and 75% of ISPs improve their profit if the end-points can choose among 5 paths towards any destination. |
