Peering Strategic Game Models for Interdependent ISPs in Content Centric Internet

Emergent content-oriented networks prompt Internet service providers (ISPs) to evolve and take major responsibility for content delivery. Numerous content items and varying content popularities motivate interdependence between peering ISPs to elaborate their content caching and sharing strategies. In this paper, we propose the concept of peering for content exchange between interdependent ISPs in content centric Internet to minimize content delivery cost by a proper peering strategy. We model four peering strategic games to formulate four types of peering relationships between ISPs who are characterized by varying degrees of cooperative willingness from egoism to altruism and interconnected as profit-individuals or profit-coalition. Simulation results show the price of anarchy (PoA) and communication cost in the four games to validate that ISPs should decide their peering strategies by balancing intradomain content demand and interdomain peering relations for an optimal cost of content delivery

Service Competition and Data-Centric Protocols for Internet Access

The Internet evolved in many aspects, from the application to the physical layers. However, the evolution of the Internet access technologies, most visible in dense urban scenarios, is not easily noticeable in sparsely populated and rural areas. In the United States, for example, the FCC identified that 50% of the census blocks have access to up to two broadband providers; however, these providers do not necessarily compete. Additionally, due to the methodology of the study, there is evidence that the number of actual customers without broadband access is higher since the FCC considers the entire block to have broadband if any customer in a block has broadband. Moreover, the average downstream connection bandwidth in the United States is 18.7 Mbps, according to the Akamai State of the Internet report, which places the US in the 10th position in the global rank. It’s worth noting that modern applications such as Ultra High Definition (UHD) video streaming requires a bandwidth of at least 25 Mbps. Newer applications such as virtual reality streaming require at least a 50 Mbps bandwidth. Additionally, urban scenarios are dominated by monopolistic and duopolistic markets, whereby network providers have little incentives to offer innovative services. In this work, we propose an open access network infrastructure along with a novel Internet architecture that allows dynamic economic relationships between users and providers through a marketplace of network services. These economic relationships have a finer granularity than today’s coarse and lengthy contracts, allowing higher competition and promoting innovation in the access market. We develop an agent-based simulator to evaluate our proposed network model and its various competition scenarios. Our simulations show that competition greatly benefits users and applications, creating the necessary incentives for providers to innovate while also benefiting consumers. The trend that resulted in sparsely populated areas lagging of the latest innovations in the access networks is also observed in wireless access networks, where the investments are focused on densely populated areas. Moreover, the rapidly increasing number of mobile devices coupled with the increasingly bandwidth demanding applications are posing a significant challenge to cellular network operators that have to increase OPEX/CAPEX and deal with higher complexity in their networks. The advances in the access technologies that brought higher speeds and lower latency also reduced the area of coverage of cellular base stations. To cope with the increase in traffic, cellular network operators have been deploying more base stations. In addition, cellular providers have adopted “all-you-can-use” price models, which led users to ramp-up their usage, further worsening congestion in the network. To address this issue, we propose a scheme that uses Device-to-Device (D2D) communication along with Information-Centric Networking (ICN) to offload traffic from cellular base stations. Then, we build on this scheme and propose a cross-layer assisted forwarding strategy to enhance communication in the MANET. In D2D communication, users can retrieve content directly from their nearby peers. However, this type of communication poses challenges to the current connection-oriented communication model, as devices can move in and out of the communication range at any time, constantly changing routing state, and nodes are subject to hidden and exposed terminal problems. ICN addresses some of these issues with inherent support for transparent caching and named content retrieval, making the network more resilient to disconnections. Our proposed scheme can offload up to 51.7% of the contents from the backhaul cellular infrastructure when requesting the content from nearby peers first. Finally, we combine the concepts of the marketplace, D2D communication, and ICN to propose a platform for decentralized and opportunistic communication that uses COTS radios to relay packets, extending the reach of the Internet to sparsely populated areas with low cost and without the lengthy contracts from commercial network providers. Our platform can potentially link the remaining part of the population that is not currently connected to the Internet

Content, Topology and Cooperation in In-network Caching

In-network caching aims at improving content delivery and alleviating pressures on network bandwidth by leveraging universally networked caches. This thesis studies the design of cooperative in-network caching strategy from three perspectives: content, topology and cooperation, specifically focuses on the mechanisms of content delivery and cooperation policy and their impacts on the performance of cache networks. The main contributions of this thesis are twofold. From measurement perspective, we show that the conventional metric hit rate is not sufficient in evaluating a caching strategy on non-trivial topologies, therefore we introduce footprint reduction and coupling factor, which contain richer information. We show cooperation policy is the key in balancing various tradeoffs in caching strategy design, and further investigate the performance impact from content per se via different chunking schemes. From design perspective, we first show different caching heuristics and smart routing schemes can significantly improve the caching performance and facilitate content delivery. We then incorporate well-defined fairness metric into design and derive the unique optimal caching solution on the Pareto boundary with bargaining game framework. In addition, our study on the functional relationship between cooperation overhead and neighborhood size indicates collaboration should be constrained in a small neighborhood due to its cost growing exponentially on general network topologies.Verkonsisäinen välimuistitallennus pyrkii parantamaan sisällöntoimitusta ja helpottamaan painetta verkon siirtonopeudessa hyödyntämällä universaaleja verkottuneita välimuisteja. Tämä väitöskirja tutkii yhteistoiminnallisen verkonsisäisen välimuistitallennuksen suunnittelua kolmesta näkökulmasta: sisällön, topologian ja yhteistyön kautta, erityisesti keskittyen sisällöntoimituksen mekanismeihin ja yhteistyökäytäntöihin sekä näiden vaikutuksiin välimuistiverkkojen performanssiin. Väitöskirjan suurimmat aikaansaannokset ovat kahdella saralla. Mittaamisen näkökulmasta näytämme, että perinteinen metrinen välimuistin osumatarkkuus ei ole riittävä ei-triviaalin välimuistitallennusstrategian arvioinnissa, joten esittelemme parempaa informaatiota sisältävät jalanjäljen pienentämisen sekä yhdistämistekijän. Näytämme, että yhteistyökäytäntö on avain erilaisten välimuistitallennusstrategian suunnitteluun liittyvien kompromissien tasapainotukseen ja tutkimme lisää sisällön erilaisten lohkomisjärjestelmien kautta aiheuttamaa vaikutusta performanssiin. Suunnittelun näkökulmasta näytämme ensin, kuinka erilaiset välimuistitallennuksen heuristiikat ja viisaan reitityksen järjestelmät parantavat merkittävästi välimuistitallennusperformanssia sekä helpottavat sisällön toimitusta. Sisällytämme sitten suunnitteluun hyvin määritellyn oikeudenmukaisuusmittarin ja johdamme uniikin optimaalin välimuistitallennusratkaisun Pareto-rintamalla neuvottelupelin kehyksissä. Lisäksi tutkimuksemme yhteistyökustannusten ja naapurustokoon funktionaalisesta suhteesta viittaa siihen, että yhteistyö on syytä rajoittaa pieneen naapurustoon sen kustannusten kasvaessa eksponentiaalisesti yleisessä verkkotopologiassa

Hierarchical network topographical routing

Within the last 10 years the content consumption model that underlies many of the assumptions about traffic aggregation within the Internet has changed; the previous short burst transfer followed by longer periods of inactivity that allowed for statistical aggregation of traffic has been increasingly replaced by continuous data transfer models. Approaching this issue from a clean slate perspective; this work looks at the design of a network routing structure and supporting protocols for assisting in the delivery of large scale content services. Rather than approaching a content support model through existing IP models the work takes a fresh look at Internet routing through a hierarchical model in order to highlight the benefits that can be gained with a new structural Internet or through similar modifications to the existing IP model. The work is divided into three major sections: investigating the existing UK based Internet structure as compared to the traditional Autonomous System (AS) Internet structural model; a localised hierarchical network topographical routing model; and intelligent distributed localised service models. The work begins by looking at the United Kingdom (UK) Internet structure as an example of a current generation technical and economic model with shared access to the last mile connectivity and a large scale wholesale network between Internet Service Providers (ISPs) and the end user. This model combined with the Internet Protocol (IP) address allocation and transparency of the wholesale network results in an enforced inefficiency within the overall network restricting the ability of ISPs to collaborate. From this model a core / edge separation hierarchical virtual tree based routing protocol based on the physical network topography (layers 2 and 3) is developed to remove this enforced inefficiency by allowing direct management and control at the lowest levels of the network. This model acts as the base layer for further distributed intelligent services such as management and content delivery to enable both ISPs and third parties to actively collaborate and provide content from the most efficient source

Performance Analysis and Optimisation of In-network Caching for Information-Centric Future Internet

The rapid development in wireless technologies and multimedia services has radically shifted the major function of the current Internet from host-centric communication to service-oriented content dissemination, resulting a mismatch between the protocol design and the current usage patterns. Motivated by this significant change, Information-Centric Networking (ICN), which has been attracting ever-increasing attention from the communication networks research community, has emerged as a new clean-slate networking paradigm for future Internet. Through identifying and routing data by unified names, ICN aims at providing natural support for efficient information retrieval over the Internet. As a crucial characteristic of ICN, in-network caching enables users to efficiently access popular contents from on-path routers equipped with ubiquitous caches, leading to the enhancement of the service quality and reduction of network loads. Performance analysis and optimisation has been and continues to be key research interests of ICN. This thesis focuses on the development of efficient and accurate analytical models for the performance evaluation of ICN caching and the design of optimal caching management schemes under practical network configurations. This research starts with the proposition of a new analytical model for caching performance under the bursty multimedia traffic. The bursty characteristic is captured and the closed formulas for cache hit ratio are derived. To investigate the impact of topology and heterogeneous caching parameters on the performance, a comprehensive analytical model is developed to gain valuable insight into the caching performance with heterogeneous cache sizes, service intensity and content distribution under arbitrary topology. The accuracy of the proposed models is validated by comparing the analytical results with those obtained from extensive simulation experiments. The analytical models are then used as cost-efficient tools to investigate the key network and content parameters on the performance of caching in ICN. Bursty traffic and heterogeneous caching features have significant influence on the performance of ICN. Therefore, in order to obtain optimal performance results, a caching resource allocation scheme, which leverages the proposed model and targets at minimising the total traffic within the network and improving hit probability at the nodes, is proposed. The performance results reveal that the caching allocation scheme can achieve better caching performance and network resource utilisation than the default homogeneous and random caching allocation strategy. To attain a thorough understanding of the trade-off between the economic aspect and service quality, a cost-aware Quality-of-Service (QoS) optimisation caching mechanism is further designed aiming for cost-efficiency and QoS guarantee in ICN. A cost model is proposed to take into account installation and operation cost of ICN under a realistic ISP network scenario, and a QoS model is presented to formulate the service delay and delay jitter in the presence of heterogeneous service requirements and general probabilistic caching strategy. Numerical results show the effectiveness of the proposed mechanism in achieving better service quality and lower network cost. In this thesis, the proposed analytical models are used to efficiently and accurately evaluate the performance of ICN and investigate the key performance metrics. Leveraging the insights discovered by the analytical models, the proposed caching management schemes are able to optimise and enhance the performance of ICN. To widen the outcomes achieved in the thesis, several interesting yet challenging research directions are pointed out

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

Proactive Mechanisms for Video-on-Demand Content Delivery

Video delivery over the Internet is the dominant source of network load all over the world. Especially VoD streaming services such as YouTube, Netflix, and Amazon Video have propelled the proliferation of VoD in many peoples' everyday life. VoD allows watching video from a large quantity of content at any time and on a multitude of devices, including smart TVs, laptops, and smartphones. Studies show that many people under the age of 32 grew up with VoD services and have never subscribed to a traditional cable TV service. This shift in video consumption behavior is continuing with an ever-growing number of users. satisfy this large demand, VoD service providers usually rely on CDN, which make VoD streaming scalable by operating a geographically distributed network of several hundreds of thousands of servers. Thereby, they deliver content from locations close to the users, which keeps traffic local and enables a fast playback start. CDN experience heavy utilization during the day and are usually reactive to the user demand, which is not optimal as it leads to expensive over-provisioning, to cope with traffic peaks, and overreacting content eviction that decreases the CDN's performance. However, to sustain future VoD streaming projections with hundreds of millions of users, new approaches are required to increase the content delivery efficiency. To this end, this thesis identifies three key research areas that have the potential to address the future demand for VoD content. Our first contribution is the design of vFetch, a privacy-preserving prefetching mechanism for mobile devices. It focuses explicitly on OTT VoD providers such as YouTube. vFetch learns the user interest towards different content channels and uses these insights to prefetch content on a user terminal. To do so, it continually monitors the user behavior and the device's mobile connectivity pattern, to allow for resource-efficient download scheduling. Thereby, vFetch illustrates how personalized prefetching can reduce the mobile data volume and alleviate mobile networks by offloading peak-hour traffic. Our second contribution focuses on proactive in-network caching. To this end, we present the design of the ProCache mechanism that divides the available cache storage concerning separate content categories. Thus, the available storage is allocated to these divisions based on their contribution to the overall cache efficiency. We propose a general work-flow that emphasizes multiple categories of a mixed content workload in addition to a work-flow tailored for music video content, the dominant traffic source on YouTube. Thereby, ProCache shows how content-awareness can contribute to efficient in-network caching. Our third contribution targets the application of multicast for VoD scenarios. Many users request popular VoD content with only small differences in their playback start time which offers a potential for multicast. Therefore, we present the design of the VoDCast mechanism that leverages this potential to multicast parts of popular VoD content. Thereby, VoDCast illustrates how ISP can collaborate with CDN to coordinate on content that should be delivered by ISP-internal multicast

Content Placement as a Key to a Content-Dominated, Highly mobile Internet

Most of the Internet traffic is content, and most of the Internet connected hosts are mobile. Our work focuses on the design of infrastructure services needed to support such a content-dominated, highly mobile Internet. In the design of these services, three sets of decisions arise frequently: (1) Content placment for selecting the locations where a content is placed, (2) request redirection for selecting the location where a particular request is served from and (3) network routing for selecting the physical path between clients and the services they are accessing. Our central thesis is that content placement is a powerful factor, and is often more powerful than redirection and routing, in determining the cost, performance and energy-related metrics for these services. In support of this thesis, we consider three types of infrastructure. Internet service provider (ISP): In an ISP carrying content-dominated traffic, we show that combinations of simple placement and routing schemes are effective in optimizing an ISP\u27s performance and cost objectives. Further, we show that effective content placement contributes more than optimizing network routing to achieve an ISP\u27s objectives. Our findings question the value of traditional ISP traffic engineering schemes that optimize routing alone, while simplifying the task of traffic engineering for the operators. Global name service (GNS): We design and implement a GNS, \auspice, that resolves names to network addresses for highly mobile entities, thereby providing a key building block for establishing communication between mobile entities in the Internet. A key distinction between \auspice\ and other name services is a {\em demand-aware} replica {placement engine} that intelligently replicates name records to provide low lookup latency, low update cost, and high availability. In our experiments, Auspice\u27s placement scheme enables it to significantly outperform commercial managed DNS providers, DHT-based replication as well as static placement schemes that use the same redirection scheme as Auspice. Content datacenter (CDC): Content datacenters cache and serve content to improve user-perceived performance for content accesses. In a CDC, we quantify the tradeoff between energy savings via consolidation and the user-perceived performance impact based on a real CDC workload. A key insight, supported via experiments, is that despite server consolidation, a simple caching scheme is able to achieve cache hit rates close to an unconsolidated datacenter, which helps mitigate the impact of consolidation on user-perceived latencies. Further, our work is the first to propose a network-aware server consolidation approach that enables additional network energy savings over network-unaware server consolidation schemes for common datacenter topologies