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Mobile edge computing is an emerging technology required to meet the very low latency requirement of 5G communication systems, where application resources are embedded within access networks. Edge computing resources can be deployed very close to end users, e.g., attachment points (AP). In such cases, the edge servers are likely to have a relatively smaller computing capacity than servers deeper in the network. This can be partially compensated by the density and scale of deployment of edge servers. To leverage such deployment, it is important to allocate services efficiently at the edge. For example, neighbor edge servers may serve users attached to a distant AP, as long as the network topology, usage, and edge application requirements, e.g., latency, enables it. In this context, user mobility is important. The user session with the edge should be migrated when needed to ensure that a mobile user continues to be served with a proper Quality of Service (QoS), typically linked to latency. In this paper, we study a service instance allocation algorithm focusing on maintaining QoS for end users, using service migration as a tool to achieve this goal. We propose a globally optimum allocation algorithm, derive a practical algorithm from it, and evaluate its use versus a heuristic and a reference algorithm.

We evaluate joint caching and pricing strategies among access networks, transit networks and content providers in an Information Centric Network (ICN). Specifically, we develop game theoretic models to study the interaction between the caching and pricing strategies among the above entities in the ICN. We first study static Nash strategies under various conditions and observe that the ICNs always choose 0-1 (all or nothing) caching strategies depending on the relative caching costs and prices at the transit ICN. We then use the insights gained to design dynamic pricing and caching strategies using a repeated game formulation. Using a model where the cost of caching changes as a function of the state of the cache, we study joint caching and pricing strategies for the access networks, transit networks and content providers, when the caching costs change linearly as well as exponentially.

Content-centric networking (CCN) adopts a receiver-driven, hop-by-hop transport approach that facilitates in-network caching, which in turn leads to multiple sources and multiple paths for transferring content. In such a case, keeping a single round trip time (RTT) estimator for a multi-path flow is insufficient as each path may experience different round trip times. To solve this problem, it has been proposed to use multiple RTT estimators to predict network condition. In this paper, we examine an alternative approach to this problem, CHoPCoP, which utilizes explicit congestion control to cope with the multiple-source, multiple-path situation. Protocol design innovations of CHoPCoP include a random early marking (REM) scheme that explicitly signals network congestion, and a per-hop fair share Interest shaping algorithm (FISP) and a receiver Interest control method (RIC) that regulate the Interest rates at routers and the receiver respectively. We have implemented CHoPCoP on the ORBIT testbed and conducted experiments under various network and traffic settings. The evaluation shows that CHoPCoP is a viable approach that can effectively deal with congestion in the multipath environment. I. INTRODUCTION During the last decade, content retrieval has dominated the Internet usage. To address the challenges posed for content retrieval, content-centric networking (CCN) (12), (15) has been proposed. Being a significant shift in the network design philosophy, CCN is centered on named content instead of host addresses. Routing towards a content is based on the content name instead of the host address, and data retrieval is initiated by issuing Interest at the content receiver. Com- pared to application-layer overlay solutions such as Content Distribution Networks (CDN) and Peer-to-peer systems (P2P), CCN holds the promise of providing a more efficient and cost- effective solution to content dissemination. CCN's unique characteristics introduce new design chal- lenges for the underlying transport protocol. First, CCN is naturally receiver-driven, since the content receiver needs to issue an Interest first in order to request a Data chunk. Second, hop-by-hop transfer is desired for CCN transport, because con- tent files can be cached along the route to improve throughput. Moreover, since a specific content is often widely disseminated and cached in the network, a CCN flow may have multiple sources - i.e., one content chunk originates from source A, while the next chunk might originate from source B. Such multi-source/multi-path transfer in CCN makes congestion estimation based on a single RTT value fall short. These features of CCN are sufficiently distinct from a traditional end-to-end host-based model that a new transport approach is called for. Recently transport protocol design for CCN has received

The advances in radio design and wireless networking, along with the growth of multimedia home entertainment technologies, is creating the concept of a cognitive digital home requiring spectrum coexistence of various devices and networks of networks. Recent work in [1] has considered a framework for resource allocation in a cognitive digital home (CDH) with a multiplicity of radio access technologies (RAT) such as cognitive radios and legacy radio devices supporting heterogeneous applications. A spectrum manager, named the home genie node (HG), is used to coordinate spectrum coexistence across different services, with degrees of freedom ranging from transmission parameters such as frequency, bandwidth, and power, to the choice of radio access technology itself. Distributed algorithms for the resource allocation problems in a CDH, namely maximizing sum rate and maximizing service capacity, which have been previously solved using centralized approaches in [1], are designed and studied using partial Lagrangian decomposition techniques in this paper.

This paper considers a Wireless Local Area Network consisting of Access Points that can provide only a limited cone of coverage. A dense access point deployment is required for such a network to provide coverage over a substantial area. Such a deployment introduces challenges associated with support of terminal mobility, backhaul management load and association. In this paper, we propose simple yet effective solutions to these problems.

We propose a PHY-authentication protocol to detect spoofing attacks in wireless networks, exploiting the rapid-decorrelation property of radio channels with distance. In this protocol, a PHY-authentication scheme that exploits channel estimations that already exist in most wireless systems, cooperates with any existing---either simple or advanced---higher-layer process, such as IEEE 802.11i. With little additional system overhead, our scheme reduces the workload of the higher-layer process, or provides some degree of spoofing protection for ``naked" wireless systems, such as some sensor networks. We describe the performance of our approach as a function of the spoofing pattern and the snapshot performance that can be easily measured through field tests. We discuss the implementation issues of the authentication protocol on 802.11 testbeds and verify its performance via field tests in a typical office building.

The advances in radio design and wireless networking, along with the growth of multimedia home entertainment technologies, is creating the concept of a cognitive digital home requiring spectrum coexistence of various devices and networks of networks. In this paper, we introduce a framework for resource allocation in a cognitive digital home with a multiplicity of radio access technologies such as cognitive radios and legacy technologies supporting heterogeneous applications. A spectrum manager, named the home genie node, is introduced to coordinate spectrum coexistence across different services, with degrees of freedom ranging from transmission parameters such as frequency, bandwidth, and power, to the choice of radio access technology itself. We study problems of sum rate maximization as well as maxmin rate allocation which are mixed integer nonlinear programs, and propose simple heuristic solutions for the same.

This paper considers the problem of generating a secret key from correlated random variables. These correlated random variables result from common BPSK modulated signals added by independent Gaussian noises. We propose a simple practical secret key construction system for this model. The performance of our proposed system is analyzed and some simulation results are provided.

We consider the problem of counting mobile stations based on feedback they provide. For this problem we propose an anonymous contentious feedback mechanism which permits efficient counting and relate the resulting estimation problem to a well know combinatorial problem of "coupon collection." Using this relationship, we analyze the estimation problem in an idealized setting. We find the ML estimator and demonstrate that it is inappropriate in this setting. We then propose an estimator which is shown to achieve good performance over a large range of parameters.

Two cooperative relaying protocols are presented and analyzed. The first emphasizes PHY cooperation via synchronized transmissions and distributed space-time coding from the Base Station (BS) and Relay Station (RS) to the User Equipment (UE) during the protocol's cooperative phase. The second protocol emphasizes MAC cooperation using different MAC flows from the BS and RS to the UE during the cooperative phase and utilizing successive interference cancellation (SIC) at the UE. This paper discusses and compares the two protocols' flexibility and performance aspects via analytical and simulation results.

Inherent connections are known to exist between common randomness generated by multiterminal source coding and channel coding on the one hand, and information theoretic secrecy generation by means of public communication on the other hand. Based on these connections, points of contact have been found recently also between secrecy generation for a special model for the latter and the combinatorial problem of tree packing in a multigraph. This paper provides a brief (and partial) survey of these links, especially those between secrecy generation and combinatorial tree packing. Our objective is to highlight specific connections between common randomness, secrecy and tree packing.

In this paper we examine the impact of using relays on the throughput and coverage of the High-Speed Packet Downlink Access (HSDPA) cellular system.We consider two cooperation schemes that can be incorporated into the existing HSPDA system with relative ease. Using a system-level simulation approach we demonstrate that relaying, when properly designed and deployed, can have a significant positive impact on the throughput and coverage of cellular systems.

We consider the secrecy inherent in the reciprocal nature of multipath fading channels and present a technique to generate a shared perfectly secret key by two terminals observing a multipath fading channel. Using this technique we quantify the secrecy that can be generated from ITU cellular channels for the 2 GHz frequency range.

We consider a pair-wise independent network where every pair of terminals in the network observes a common pair-wise source that is independent of all the sources accessible to the other pairs. We propose a method for secret key agreement in such a network that is based on well-established point-to-point techniques and repeated application of the one-time pad. Three specific problems are investigated. 1) Each terminal's observations are correlated only with the observations of a central terminal. All these terminals wish to generate a common secret key. 2) In a pair-wise independent network, two designated terminals wish to generate a secret key with the help of other terminals. 3) All the terminals in a pair-wise independent network wish to generate a common secret key. A separate protocol for each of these problems is proposed. Furthermore, we show that the protocols for the first two problems are optimal and the protocol for the third problem is efficient, in terms of the resulting secret key rates., submitted to 2007 IEEE International Symposium on Information Theory

We present a method for secrecy extraction from jointly Gaussian random sources. The approach is motivated by and has applications in enhancing security for wireless communications. The problem is also found to be closely related to some well known lossy source coding problems.

We consider the broadcast-relay channel: a broadcast channel where receivers are permitted to assist in the distribution of data to other receivers by relaying. We extend the previous results and demonstrate that effective transmission strategies can be derived by combining well-known techniques for broadcast and relay channels. Additionally, we derive new outer bounds to capacity regions

In this paper, we analyze the effect of scaling laws in random heterogeneous networks. This paper describes a square grid with shortcuts and a scaling law with wired shortcuts