Modeling Tiered Pricing in the Internet Transit Market

ISPs are increasingly selling "tiered" contracts, which offer Internet connectivity to wholesale customers in bundles, at rates based on the cost of the links that the traffic in the bundle is traversing. Although providers have already begun to implement and deploy tiered pricing contracts, little is known about how such pricing affects ISPs and their customers. While contracts that sell connectivity on finer granularities improve market efficiency, they are also more costly for ISPs to implement and more difficult for customers to understand. In this work we present two contributions: (1) we develop a novel way of mapping traffic and topology data to a demand and cost model; and (2) we fit this model on three large real-world networks: an European transit ISP, a content distribution network, and an academic research network, and run counterfactuals to evaluate the effects of different pricing strategies on both the ISP profit and the consumer surplus. We highlight three core findings. First, ISPs gain most of the profits with only three or four pricing tiers and likely have little incentive to increase granularity of pricing even further. Second, we show that consumer surplus follows closely, if not precisely, the increases in ISP profit with more pricing tiers. Finally, the common ISP practice of structuring tiered contracts according to the cost of carrying the traffic flows (e.g., offering a discount for traffic that is local) can be suboptimal and that dividing contracts based on both traffic demand and the cost of carrying it into only three or four tiers yields near-optimal profit for the ISP

Preventing Attacks on BGP Policies: One Bit is Enough

The Internet is comprised of many autonomous systems (AS) managed by independent entities that use the Border Gateway Protocol (BGP) to route their traffic. Although it is the de facto standard for establishing paths across the Internet, BGP is not a secure protocol and the Internet infrastructure often experiences attacks, such as prefix hijacking and attribute mangling, incurring great costs to ASes that experience them. Various solutions have been proposed in response to these attacks, such as Secure BGP, but they do not address traffic attraction attacks that stem from export policy violations. In these attacks, malicious ASes can introduce paths that are legitimate from the protocol standpoint and yet malicious to the users of that protocol. Although these attacks have been studied before, no solution has yet been proposed. In this paper, we thoroughly characterize this set of attacks and propose a very lightweight and effective scheme to address them. Our scheme requires no manual configuration. We show that even if only a small fraction of ASes deploy our scheme, the amount of possible attacks reduces by on order of magnitude

The Case for Microcontracts for Internet Connectivity

This paper introduces microcontracts, which are contracts for "slices" of the Internet connectivity along dimensions such as time, destination, volume, and application type. Microcontracts are motivated by the observation that Internet service providers carry traffic for different classes of customers that use the ISP's resources in a variety of different ways and, hence, impose different costs on the ISPs. For example, customers have little incentive to move less important traffic from a peak time interval unless their contract reflects the ISP's costs in that time interval. To address this inefficiency, microcontracts divide connectivity into fine-grained units so that prices more directly reflect the costs that the ISP bears for delivering the connectivity at that time. We explore the feasibility of applying microcontracts in realistic Internet service provider settings by characterizing the traffic patterns from a transit network along two specific dimensions: time-of-day and distance travelled. We argue that microcontracts are both feasible and advantageous to both buyers and sellers of Internet connectivity. We develop a model to help ISPs derive customer demand functions from observed traffic patterns; using this model, we show that making contracts for Internet connectivity more fine-grained can improve the aggregate gain of an ISP and its customers

Wide-area route control for online services

Accelerated by on-demand computing, the number and diversity of the Internet services is increasing. Such online services often have unique requirements for the underlying wide-area network: For instance, online gaming service might benefit from low delay and jitter paths to client, while online data backup service might benefit from cheaper paths. Unfortunately, today's Internet does not accommodate fine-grained, service-specific wide-area route control. In this dissertation, I achieve the following goals: 1) improve the access to the routes, 2) quantify the benefits of fine-grained route control, and 3) evaluate the efficiency of current payment schemes for the wide-area routes. * Improving access to wide-area route control. Online services face significant technological and procedural hurdles in accessing the routes: Each service in need to control the Internet routes, has to obtain own equipment, Internet numbered resources, and establish contracts with upstream ISPs. In this dissertation, I propose and describe implementation and deployment of a secure and scalable system which provides on-demand access to the Internet routes. In setting such as cloud data center, the system can support multiple online services, providing each service with an illusion of direct connectivity to the neighboring Internet networks, which, for all practical purposes, allows services to participate fully in the Internet routing. * Quantifying the benefits of fine-grained route control. Even if online services are presented with wide-area route choice, it is not clear how much tangible benefit such choice provides. Most modern Online Service Providers (OSP) rely primarily on the content routing to improve network performance between the clients and the replicas. In this dissertation, I quantify the potential benefit the OSPs can gain if they perform a joint network and content routing. Among other findings, I find that by performing joint content and network routing, OSPs can achieve 22% larger latency reduction than can be obtained by content routing alone. * Modeling and evaluating the efficiency of the current payment schemes for wide-area routes. Finally, increasing diversity and sophistication of the online services participating in the Internet routing poses a challenge to payment models used in today's Internet. Service providers today charge business customers a blended rate: a single, "average" price for unit of bandwidth, without regard to cost or value of individual customer's flows. In my dissertation, I set to understand how efficient this payment model is and if more granular payment model, accounting for the cost and value of different flows could increase the ISP profit and the consumer surplus. I develop an econometric demand and cost model and map three real-world ISP data sets to it. I find that ISPs can indeed improve the economic efficiency with just a few pricing tiers.PhDCommittee Chair: Nick Feamster; Committee Member: Ellen Zegura; Committee Member: Mostafa Ammar; Committee Member: Ramesh Johari; Committee Member: Vijay V. Vaziran

Managing BGP Routes with a BGP Session Multiplexer

This paper presents the design, implementation, and evaluation of BGP-Mux, a system for providing multiple clients access to a common set of BGP update streams from multiple BGP peers. By providing multiple clients access to the same set of BGP feeds, BGP-Mux facilitates many applications, including: (1) scalable, real-time monitoring of BGP update feeds; (3) new routing architectures that require access to all BGP routing updates from neighboring ASes (as opposed to just the best BGP route for each destination); and (2) virtual networks running on shared infrastructure that share common underlying network connectivity. We have implemented BGP-Mux through by configuring existing features in the Quagga software router; we have deployed BGP-Mux on VINI and evaluated its scalability and performance in a controlled environment on the Emulab testbed

WideArea Route Control for Distributed Services

Many distributed services would benefit from control over the flow of traffic to and from their users, to offer better performance and higher reliability at a reasonable cost. Unfortunately, although today’s cloud-computing platforms offer elastic computing and bandwidth resources, they do not give services control over wide-area routing. We propose replacing the data center’s border router with a Transit Portal (TP) that gives each service the illusion of direct connectivity to upstream ISPs, without requiring each service to deploy hardware, acquire IP address space, or negotiate contracts with ISPs. Our TP prototype supports many layer-two connectivity mechanisms, amortizes memory and message overhead over multiple services, and protects the rest of the Internet from misconfigured and malicious applications. Our implementation extends and synthesizes open-source software components such as the Linux kernel and the Quagga routing daemon. We also implement a management plane based on the GENI control framework and couple this with our four-site TP deployment and Amazon EC2 facilities. Experiments with an anycast DNS application demonstrate the benefits the TP offers to distributed services. 1