A Game Theoretical study of Peering vs Transit in the Internet

International audienceWe propose a model for network optimization in a non-cooperative game setting with specific reference to the Internet connectivity. We refer to the general model shown in internal report [1], where Autonomous Systems (AS) decisions on link creation and traffic routing are strategically based on realistic interconnection costs, keeping into account the peering/transit dichotomy. Equilibria existence and convergence results were obtained in [1] only for a specific toy problem, while here we study larger scale scenarios which better fit the complex nature of the Internet. We are able to show that equilibria existence and convergence properties still hold for many possible generalizations, yet not all of them, and provide a specific example for which the system enters in a never-ending oscillation. Thanks to the use of simulations we covered those scenarios for which analytic results could not be obtained, thus analyzing a broad variety of general cases which were not studied in [1]. Simulation shows that the system, in the vast majority of cases, converges to an equilibrium. Very interestingly, even in asymmetric scenarios the equilibrium reached suggests that players tend to be symmetric with respect to the peering exchange points and send their asymmetric traffic quota via the transit service providers

Internet Peering as a Network of Relations

We apply results from recent theoretical work on networks of relations to analyze optimal peering strategies for asymmetric ISPs. It is shown that - from a network of relations perspective – ISPs’ asymmetry in bilateral peering agreements need not be a problem, since when these form a closed network, asymmetries are pooled and information transmission is faster. Both these effects reduce the incentives for opportunism in general, and interconnection quality degradation in particular. We also explain why bilateral monetary transfers between asymmetric ISPs (Bilateral Paid Peering), though potentially good for bilateral peering, may have rather negative effects on the sustainability of the overall peering network

Internet Peering as a Network of Relations

We apply results from recent theoretical work on networks of relations to analyze optimal peering strategies for asymmetric ISPs. It is shown that - from a network of relations perspective – ISPs’ asymmetry in bilateral peering agreements need not be a problem, since when these form a closed network, asymmetries are pooled and information transmission is faster. Both these effects reduce the incentives for opportunism in general, and interconnection quality degradation in particular. We also explain why bilateral monetary transfers between asymmetric ISPs (Bilateral Paid Peering), though potentially good for bilateral peering, may have rather negative effects on the sustainability of the overall peering network.

Congestion, Private Peering and Capacity Investment on the Internet.

This paper presents a model of private bilateral and multilateral peering arrangements between Internet backbone providers when the network is congested. We study how different forms of interconnection and the competitive conditions of the market affect backbones' investments in network and peering point capacities. We show that network and peering point capacities are equilibrium complements; increasing competition reduces capacity investments (under-investment), thus worsening the quality of service both with multilateral and bilateral peering; under bilateral peering the inefficiency is less severe. Because of under-investment, welfare may be lower when the market is more competitive. We also show that asymmetries between backbones, which can take the form of uneven content distribution or product differentiation, may reduce under-investment and improve the quality of service. The introduction of an "inverse capacity interconnection fee" where providers pay each other a fee which is negatively correlated with their installed capacity may play the role of a coordinating mechanism towards a Pareto superior outcome.Internet, peering, congestion, QoS, capacity investment, interconnection

Interconnection and Competition Among Asymmetric Networks in the Internet Backbone Market

We examine the interrelation between interconnection and competition in the internet backbone market.Networks asymmetric in size choose among different interconnection regimes and compete for end-users.We show that a direct interconnection regime, Peering, softens competition compared to indirect interconnection since asymmetries become less influential when networks peer.If interconnection fees are paid, the smaller network pays the larger one. Sufficiently symmetric networks enter a Peering agreement while others use an intermediary network for exchanging traffic.This is in line with considerations of a non-US policy maker.In contrast, US policy makers prefer Peerings among relatively asymmetric networks.Internet Backbone;Endogenous Network Interconnection;Asymmetric Networks;Two-Way Access Pricing

Rethinking Routing and Peering in the era of Vertical Integration of Network Functions

Content providers typically control the digital content consumption services and are getting the most revenue by implementing an all-you-can-eat model via subscription or hyper-targeted advertisements. Revamping the existing Internet architecture and design, a vertical integration where a content provider and access ISP will act as unibody in a sugarcane form seems to be the recent trend. As this vertical integration trend is emerging in the ISP market, it is questionable if existing routing architecture will suffice in terms of sustainable economics, peering, and scalability. It is expected that the current routing will need careful modifications and smart innovations to ensure effective and reliable end-to-end packet delivery. This involves new feature developments for handling traffic with reduced latency to tackle routing scalability issues in a more secure way and to offer new services at cheaper costs. Considering the fact that prices of DRAM or TCAM in legacy routers are not necessarily decreasing at the desired pace, cloud computing can be a great solution to manage the increasing computation and memory complexity of routing functions in a centralized manner with optimized expenses. Focusing on the attributes associated with existing routing cost models and by exploring a hybrid approach to SDN, we also compare recent trends in cloud pricing (for both storage and service) to evaluate whether it would be economically beneficial to integrate cloud services with legacy routing for improved cost-efficiency. In terms of peering, using the US as a case study, we show the overlaps between access ISPs and content providers to explore the viability of a future in terms of peering between the new emerging content-dominated sugarcane ISPs and the healthiness of Internet economics. To this end, we introduce meta-peering, a term that encompasses automation efforts related to peering – from identifying a list of ISPs likely to peer, to injecting control-plane rules, to continuous monitoring and notifying any violation – one of the many outcroppings of vertical integration procedure which could be offered to the ISPs as a standalone service

Peering vs Transit: a Game Theoretical model for Autonomous Systems connectivity

International audienceWe propose a model to analyze the decisions taken by an Autonomous System (AS) when joining the Internet. We first define a realistic model for the interconnection costs incurred and then we use this cost model to perform a game theoretic analysis of the decisions related to the creation of new links in the Internet. The proposed model doesn't fall into the standard category of routing games, hence we devise new tools to solve it by exploiting peculiar properties of our game. We prove analytically the existence of multiple equilibria for specific cases, and provide an algorithm to compute the stable ones. The analysis of the model's outcome highlights the existence of a Price of Anarchy (PoA) and a Price of Stability (PoS), originated by the non-cooperative behavior of the ASes, which optimize their cost function in a selfish and decentralized manner. We further observe the presence of competition between the facilities providing either transit or peering connectivity, caused by the cost differences between these two interconnection strategies