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The advent of the edge computing network paradigm places the computational and storage resources away from the data centers and closer to the edge of the network largely comprising the heterogeneous IoT devices collecting huge volumes of data. This paradigm has led to considerable improvement in network latency and bandwidth usage over the traditional cloud-centric paradigm. However, the next generation networks continue to be stymied by their inability to achieve adaptive, energy-efficient, timely data transfer in a dynamic and failure-prone environment—the very optimization challenges that are dealt with by biological networks as a consequence of millions of years of evolution. The transcriptional regulatory network (TRN) is a biological network whose innate topological robustness is a function of its underlying graph topology. In this article, we survey these properties of TRN and the metrics derived therefrom that lend themselves to the design of smart networking protocols and architectures.We then reviewa body of literature on bio-inspired networking solutions that leverage the stated properties of TRN. Finally, we present a vision for specific aspects of TRNs that may inspire future research directions in the fields of large-scale social and communication networks. [ABSTRACT FROM AUTHOR]

We study the interaction of the programming construct "new," which generates statically scoped names, with communication via messages on channels. This interaction is crucial in security protocols, which are the main motivating examples for our work; it also appears in other programming-language contexts. We define the applied pi calculus, a simple, general extension of the pi calculus in which values can be formed from names via the application of built-in functions, subject to equations, and be sent as messages. (In contrast, the pure pi calculus lacks built-in functions; its only messages are atomic names.)We develop semantics and proof techniques for this extended language and apply them in reasoning about security protocols. This article essentially subsumes the conference paper that introduced the applied pi calculus in 2001. It fills gaps, incorporates improvements, and further explains and studies the applied pi calculus. Since 2001, the applied pi calculus has been the basis for much further work, described in many research publications and sometimes embodied in useful software, such as the tool ProVerif, which relies on the applied pi calculus to support the specification and automatic analysis of security protocols. Although this article does not aim to be a complete review of the subject, it benefits from that further work and provides better foundations for some of it. In particular, the applied pi calculus has evolved through its implementation in ProVerif, and the present definition reflects that evolution. [ABSTRACT FROM AUTHOR]

Low-power wireless communication is a central building block of cyber-physical systems and the Internet of Things. Conventional low-power wireless protocols make avoiding packet collisions a cornerstone design choice. The concept of synchronous transmissions challenges this view. As collisions are not necessarily destructive, under specific circumstances, commodity low-power wireless radios are often able to receive useful information even in the presence of superimposed signals from different transmitters. We survey the growing number of protocols that exploit synchronous transmissions for higher robustness and deficiency as well as unprecedented functionality and versatility compared to conventional designs. The illustration of protocols based on synchronous transmissions is cast in a conceptional framework we establish, with the goal of highlighting differences and similarities among the proposed solutions. We conclude this article with a discussion on open questions and challenges in this research field. [ABSTRACT FROM AUTHOR]

Peer-to-peer systems rely on a scalable overlay network that enables efficient routing between its members. Hypercubic topologies facilitate such operations while each node only needs to connect to a small number of other nodes. In contrast to static communication networks, peer-to-peer networks allow nodes to adapt their neighbor set over time in order to react to join and leave events and failures. This article shows how to maintain such networks in a robust manner. Concretely, we present a distributed and self-stabilizing algorithm that constructs a (slightly extended) skip graph, SKIP+, in polylogarithmic time from any given initial state in which the overlay network is still weakly connected. This is an exponential improvement compared to previously known self-stabilizing algorithms for overlay networks. In addition, our algorithm handles individual joins and leaves locally and efficiently. [ABSTRACT FROM AUTHOR]

Blockchain technology can be extensively applied in diverse services, including online micro-payments, supply chain tracking, digital forensics, health-care record sharing, and insurance payments. Extending the technology to the Internet of things (IoT), we can obtain a verifiable and traceable IoT network. Emerging research in IoT applications exploits blockchain technology to record transaction data, optimize current system performance, or construct next-generation systems, which can provide additional security, automatic transaction management, decentralized platforms, offline-to-online data verification, and so on. In this article, we conduct a systematic survey of the key components of IoT blockchain and examine a number of popular blockchain applications. In particular, we first give an architecture overview of popular IoT-blockchain systems by analyzing their network structures and protocols. Then, we discuss variant consensus protocols for IoT blockchains, and make comparisons among different consensus algorithms. Finally, we analyze the traffic model for P2P and blockchain systems and provide several metrics. We also provide a suitable traffic model for IoT-blockchain systems to illustrate network traffic distribution. [ABSTRACT FROM AUTHOR]

Underwater wireless sensor networks (UWSNs) will pave the way for a new era of underwater monitoring and actuation applications. The envisioned landscape of UWSN applications will help us learn more about our oceans, as well as about what lies beneath them. They are expected to change the current reality where no more than 5% of the volume of the oceans has been observed by humans. However, to enable large deployments of UWSNs, networking solutions toward efficient and reliable underwater data collection need to be investigated and proposed. In this context, the use of topology control algorithms for a suit-able, autonomous, and on-the-fly organization of the UWSN topology might mitigate the undesired effects of underwater wireless communications and consequently improve the performance of networking services and protocols designed for UWSNs. This article presents and discusses the intrinsic properties, potentials, and current research challenges of topology control in underwater sensor networks. We propose to classify topology control algorithms based on the principal methodology used to change the network topology. They can be categorized in three major groups: power control, wireless interface mode management, and mobility assisted-based techniques. Using the proposed classification, we survey the current state of the art and present an in-depth discussion of topology control solutions designed for UWSNs. [ABSTRACT FROM AUTHOR]

Byzantine Fault Tolerant (BFT) protocols have the ability to work correctly even when up to a threshold f of system servers are compromised. This makes them appealing for the construction of critical systems connected to the Internet, which are constantly a target for cyber attacks. BFT protocols differ based on the kind of application, deployment settings, performance, access control mechanisms, number of servers in the system, and protocol implementation. The large number of protocols present in the literature and their differences make it difficult for a system builder to choose the solution that best satisfies the requirements of the system that he wants to build. In particular, the main difference among BFT protocols lies in their system models: server-side versus client-side. In the server-side model each client relies on the system to consistently order and replicate updates, while in the client-side model each client actively participates in the protocol. In this article, we classify BFT protocols as server-side or client-side. We analyze the trade-offs between the two models, describe systems that use these models and the trade-offs they choose, highlight the research gaps, and provide guidelines to system builders in order to choose the solution that best satisfies their needs. [ABSTRACT FROM AUTHOR]

Computer network protocols define the rules in which two entities communicate over a network of unique hosts. Many protocol specifications are unknown, unavailable, or minimally documented, which prevents thorough analysis of the protocol for security purposes. For example, modern botnets often use undocumented and unique application-layer communication protocols to maintain command and control over numerous distributed hosts. Inferring the specification of closed protocols has numerous advantages, such as intelligent deep packet inspection, enhanced intrusion detection system algorithms for communications, and integration with legacy software packages. Themultitude of closed protocols coupled with existing time-intensive reverse engineering methodologies has spawned investigation into automated approaches for reverse engineering of closed protocols. This article summarizes and organizes previously presented automatic protocol reverse engineering tools by approach. Approaches that focus on reverse engineering the finite state machine of a target protocol are separated from those that focus on reverse engineering the protocol format. [ABSTRACT FROM AUTHOR]

Several Peer-to-Peer (P2P) protocols and applications have been developed to allow file distribution/sharing, video and music streaming, and data and information dissemination. These P2P systems are regularly used by a large number of users, both in desktop and mobile environments, and they generate a remarkable portion of the overall Internet traffic. However, many common P2P protocols and applications were designed neglecting the energy problem. In fact, they often require always-on devices in order to work properly, thus producing significant energy waste. The problem is even more relevant in the mobile context, since the battery lifetime of mobile devices is limited. Therefore, energy efficiency in P2P systems is a highly debated topic in the literature. New P2P approaches--more energy efficient than traditional client/server solutions--have been proposed. In addition, several improvements to existing P2P protocols have been introduced to reduce their energy consumption. In this article, we present a general taxonomy to classify state-of-the-art approaches to the energy problem in P2P systems and applications. Then, we survey themain solutions available in the literature, focusing on three relevant classes of P2P systems and applications: file sharing/distribution, content streaming, and epidemics. Furthermore, we outline open issues and provide future research guidelines for each class of P2P systems. [ABSTRACT FROM AUTHOR]

This article explains the full reconfigurable multidecree Paxos (or multi-Paxos) protocol. Paxos is by no means a simple protocol, even though it is based on relatively simple invariants. We provide pseudocode and explain it guided by invariants. We initially avoid optimizations that complicate comprehension. Next we discuss liveness, list various optimizations that make the protocol practical, and present variants of the protocol. [ABSTRACT FROM AUTHOR]

Key management is required for basic security services of confidentiality, integrity, and data source authentication. Wireless sensor networks (WSNs) are a challenging environment to provide such services due to the resource constraints and the increased likelihood of nodes to be captured. Various key management techniques were proposed that trade off resilience to node capture and overhead in terms of communication and memory. We identify the main factors influencing the design space of key management protocols for sensor networks and describe representative protocols that trade off the number of links established, communication overhead, and resilience to node capture. These trade-offs are due to using direct, pathbased, or multipath-based communication to establish secure links. We propose a new multipath protocol relying on an encoding scheme tailored for WSNs and analyze the effects of key pre-distribution on multipath key establishment. We provide extensive simulations to understand the trade-offs between resilience to node compromise and communication overhead under numerous network scenarios. This comparison highlights the tradeoffs between these vastly different key management schemes. For the newer class of key management schemes--multipath based--we quantify experimentally the additional communication overhead required for extra paths and the improvement in resilience from using these paths. [ABSTRACT FROM AUTHOR]