Nowadays, most network systems are based on fixed and reliable infrastructure, but with Internet of Things (IoT), smart home and smart city systems are used more and more in mobile scenarios and vehicles become connected. Often low power mobile devices are supported by cloud computing capabilities. However, infrastructure may not be available everywhere, where mobile devices are used and local information is often only required locally, thus do not need to be uploaded into the cloud. SCoIoT is based on novel Information Centric Networking communication pattern and is designed to support cooperative computations without requiring new infrastructure or even in absence of infrastructure due to the device to device communication pattern. Thereby, nodes voluntarily participate in computations and help to spread the computation to enable further nodes to participate in the computation and to share the results. SCoIoT utilizes Append-only-Log technology for synchronization and verification of requests and results.

Solid is a moderate re-decentralization architecture for the Web. In Solid, applications fetch data from storage providers called “pods” which implement discretionary access control, permitting users to grant and revoke access rights and thus keeping control over their data. In this paper, we propose to apply an additional de-verticalization by introducing IPFS as a common backend for Solid pods, the goal being to prevent pod provider lock-in and permitting users to consider “self-poding” where the heavy persistency task is out-sourced to IPFS. We have implemented this Solid-over-IPFS architecture using the open-source “Community Solid Server” and successfully ran several Solid applications over IPFS.

Named Function Networking (NFN) is an extension for Information Centric Networking (ICN) to execute computation inside the Network. Thereby, NFN consists of two contributions: A workflow definition and a resolution strategy. The ICN communication model enables NFN to reuse already computed results by using the network's content store. To resolve a computation, NFN first tries to find a cached result and only if no result was found, the computation is executed - so-called FoX (Find or Execute) resolution strategy. Initially, NFN was optimized for cloud computing and data center computing next to the big data objects. However, new trends like IoT and edge computing describe other requirements to network computations (e.g. dynamic computations of automotive services at the edge). In this paper, we explore how the resolution strategy can be modified to fit to IoT scenarios without changing the workflow definition. Based on two exemplary IoT use cases (home automation and automotive IOT), new resolution strategies will be presented.

Chemical algorithms are statistical control algorithms described and represented as chemical reaction networks. They are analytically tractable, they reinforce a deterministic state-to-dynamics relation, they have configurable stability properties, and they are directly implemented in state space using a high-level visual representation. These properties make them attractive solutions for traffic shaping and generally the control of dynamics in computer networks. In this paper, we present a framework for deploying chemical algorithms on field programmable gate arrays. Besides substantial computational acceleration, we introduce a low-overhead approach for hardware-level programmability and re-configurability of these algorithms at runtime, and without service interruption. We believe that this is a promising approach for expanding the control-plane programmability of software defined networks (SDN), to enable programmable network dynamics. To this end, the simple high-level abstractions of chemical algorithms offer an ideal northbound interface to the hardware, aligned with other programming primitives of SDN (e.g., flow rules).

Although very similar, Information Centric Networking implementations like CCNx or NDN have not converged (yet). Moreover, high-level extensions like named functions and low-level considerations for IoT or logical link control will lead to even more variety in formats and experiments, also including slight (and not well-documented) changes of the ICN protocols' behavior. Based on our experience with the multi-protocol implementation CCN-lite, we have developed a domains-specific intermediate language ICCL (Information Centric Core Language). Initially, the purpose of ICCL was to document the common as well as diverging aspects of the various approaches and to provide a run-time which can directly execute an ICCL program. But as it turned out, ICCL became a tool beyond modeling the behavior of ICN forwarders. For example, by including appropriate primitives to access local data sources, one can now seamlessly include in an ICCL program the access to data repositories or serve on-demand data from sensors. This enables easy programmability of network functionality and contributes to “do-it-yourself” networking. We discuss the benefit of this fusion for the development of ICN functionality and report on performance measurements for our prototype system.

We present the logical design of a trust engine for Information-Centric Networking (ICN) that is capable of efficiently and correctly verifying content integrity and authenticity. Our primary contribution is the synthesis and unified treatment of four different and popular trust models. We show in which operational aspects they vary and emphasize which parts of the verification mechanics are invariant. The verifier logic is expressed in Prolog to show its simplicity (abstracting away, e.g., procedural certification chain verification steps) and to highlight subtle errors that can occur in the use and enforcement of trust models. The details of an implementation of our trust engine in the CCNx network stack are presented to demonstrate its viability and general modularity. A simplistic interface enables the trust engine to be easily ported to any ICN-style network software. Finally, we demonstrate how application instantiations of various trust models are natively supported by the trust engine to illustrate its flexibility.

In wireless sensor and actor networks (WSANs), nodes collaborate to accomplish distributed sensing and computation. One of the most attractive features is that global macro- behaviors in the network emerge from local micro-actions in and interactions between nodes. In this paper, we review a recently proposed approach, which bases on a chemical metaphor and its related theory, to design, analyze, and implement systems with such an emerging property. As an example of distributed, emerging computation in WSNs, we extend an existing gossip-like chemistry-inspired protocol (the “Disperser”) and propose a new chemically driven solution to consensus problems that is applicable in WSNs. We analyze it with a signal processing approach and validate results through simulations. The proposed chemical algorithm is not based on the iterative packet-exchange but rather on a continuous rate-modulation. The algorithm is thought to lie at the physical layer and to directly control the basic transmission hardware of the nodes in a sort of protocol-less operation mode.

The Content Centric Network (CCNx) protocol introduces a new routing and forwarding paradigm for the waist of the future Internet architecture. Below CCN, a volatile set of transport and flow-control strategies is envisioned, which can match better different service requirements, than current TCP/IP technology does. Although a broad range of possibilities has not been explored yet, there are already several proponents of strategies that come close to TCP's well-known flow control mechanism (timeout-driven, window-based, and AIMD- operated). In this paper, we carry out an empirical exploration of some proposed strategies in order to assert their feasibility and efficiency. Our contributions are twofold: First, we establish if receiver-based, timeout-driven, AIMD operated flow-control on Interest transmissions is sufficiently effective for CCN in a future Internet deployment, where it may co-exist with TCP. In this process we compare the performance of three different variants of this strategy, in presence of multi-homed content in the network (one of them proposed by the authors). Second, we provide indicators for the general efficiency of timeout-based flow-control at the CCN receiver, in presence of in-network caching, and exhibit some of the challenges faced by such strategies.

Traffic-shaping algorithms, such as congestion avoidance or rate limiting for cloud services, control the dynamics of packet flows in a distributed setting. However, despite their significance in networking, it is still hard to design them, to predict their dynamic behavior, and to prove their robustness. With the help of a simple chemical metaphor, we recently proposed a novel engineering framework for designing, executing, and analyzing traffic-shaping algorithms: by letting packets react akin to chemical molecules, the design of (distributed) flow-control algorithms becomes drawing reaction networks. In this way, we gain in analyzability: the related fluid model, describing the emergent behavior of the overall system, can be derived from the corresponding reaction networks automatically. In this article, we describe how to fine-tune chemical algorithms. We therefore analyze their transient behavior in order to reveal the semantics and sensitivity of key parameters. Methods from different domains assist us in this endeavor: We first linearize the fluid model as proposed in Metabolic Control Analysis, we then describe it in control-theoretic terms, and finally, we characterize its sensitivity in the frequency domain. We demonstrate the feasibility and reveal the limits of our method by applying it to a chemical algorithm for distributed rate control.

A challenging problem when engineering network and communication protocols is to predict and formally describe the dynamic behavior of a protocol. Chemical Networking Protocols (CNPs) offer the opportunity to transpose the good and well-understood analyzability of chemical reactions to networking protocols, not only at the design stage of protocols, but also for the study of their dynamic behavior. In this paper we focus on this latter aspect and we demonstrate how signal processing techniques from classical signal and control theory can be employed in the study of the average flow properties of CNPs. Our analysis methods include a model linearization as proposed in Metabolic Control Analysis, a statespace description classically used in control theory, and the system's characterization in the frequency domain, which is central to signal theory. We demonstrate the feasibility of our method by applying it to an actual congestion control protocol that models TCP's behavior. With our contribution, CNP designers can easily determine the key parameters of their protocols and understand how to calibrate them in order to obtain the desired behavior.

Designing dynamically robust protocols is not a simple task with current classic work-conserving scheduling, where packets are sent out as soon as processing and transmission capacity is available. We show that deviating from this fundamental queuing assumption leads to much more controllable and analyzable forms of protocols. At the core of our work is a queue-scheduling discipline based on the chemical "Law of Mass Action" (LoMA) that serves a queue with a rate proportional to its fill level. In this paper we introduce our LoMA-scheduling approach and provide a solid mathematical framework adopted from chemistry that simplifies the analysis of the corresponding queueing networks, including the prediction of the underlying protocols' dynamics. We demonstrate the elegance of our model by implementing and analyzing a TCP-compatible "chemical" congestion control algorithm C3A with only a few interacting queues (another novelty of our approach). We also show the application of our theory to gossip protocols, explain an effective implementation of the scheduler and discuss possibilities of how to integrate mass-action scheduling into traditional networking environments.

Greedy geometric routing is one of the most appealing options for sensor and ad-hoc networks due to its simplicity, scalability and mainly stateless operation. However, its performance may vary when a low-dimensional embedding results in a graph with void regions and local minima locations. In this paper, we advocate the benefits of clustering for improving the performance of greedy routing over an existing embedding. Our contributions include: (a) an examination of the effects of clustering on influencing routing near void regions and overcoming problems with local minima, (b) a generic framework for enabling a cluster view for greedy routes, that can work with any low-dimensional embedding, and (c) a quantitative evaluation of the performance improvement we achieve, using some reference clustering approaches, over a number of virtual coordinate systems for geometric routing.

High-level programming abstractions (i.e. "middleware") primarily aim at: abstracting from heterogeneity and hardware complexity, simplification of (re-)programming, specifying system behavior in a post-hoc fashion. So far in the Wireless Sensor Networks (WSNs) domain the focus has been put mainly on the first two tasks and the application level of the last one. The meta-code approach we propose offers mechanisms to support low-level programming (e.g. time-sync, routing schemes, etc) on pre-deployed networks still requiring minimal knowledge of network characteristics. Its sole task is to provide tools to finely tune existing infrastructures with an "assembler-level" granularity in order to create task-specific highly optimized configurations. The meta-code is being designed taking into account specific requirements of WSNs, namely limited computational resources and power consumption.

The objective of autonomic networking is to enable the autonomous formation and parametrization of nodes and networks by letting protocols sense and adapt to the networking environment at run time. Besides its dynamic aspects, a core requirement of autonomic networking is to define a structured framework and execution environment that enables algorithms to operate in a continously changing environment. This paper presents the major design principles of the Autonomic Network Architecture (ANA) and reports on a first implementation. The guiding principle of ANA is to strive for flexibility and genericity at all levels of the architecture. In our approach we explicitly avoid to impose a "one-size-fits-all" architecture (where communication protocols and paradigms are fixed by the architecture). To this end, ANA introduces generic abstractions, for example "information dispatch points" instead of addressable endpoints, as well as communication primitives that support network heterogeneity, adaptability, and evolution. These core abstractions allow for the coexistance of multiple and diverse networking styles and protocols. With the public release of the ANA prototype, we aim at federating autonomics related networking projects, enabling different actors to share, compare, and build upon each other¿s work. The ANA runtime can host clean slate network designs as well as legacy Internet technology and serves as a platform for demonstrating autonomic communication principles.

A majority of network architectures aim at solving specific shortcomings of the original Internet architecture. While providing solutions for the particular problems, they often lack in flexibility and do not provide general concepts for future networking requirements. In contrast, we introduce a network architecture that aims to be versatile enough to serve as a foundation for the future Internet. The main pillars of our architecture are communication pivots called information dispatch points (IDPs) which embed the concept of modularity at all levels of the architecture. IDPs completely decouple functional entities by means of indirection thus enabling evolving protocol stacks. Our architecture also provides a consistent application programming interface (API) to access node-local or network-wide functionality. In addition to the description of this architecture, we report about a working prototype of the architecture and we give examples of its application.

The ANA (Autonomic Network Architecture) project aims at providing a framework to flexibly host, interconnect, and federate multiple heterogeneous networks in an autonomic way, i.e. without requiring active human intervention. The guiding design principle is to strive for a maximum degree of flexibility at all levels of the architecture in order to inherently support heterogeneity and evolution. This paper describes the core abstractions and concepts of ANA (as defined during the first year of the project) and introduces their basic operation and interaction. While not autonomic themselves, the core architectural principles of ANA will enable autonomicity by not imposing a "one-size-fits-all" approach where protocols and paradigms are fixed by the architecture. We indeed argue that only the capacity of the network to be polyfunctional and fully adaptable will justify the label ' autonomic'. A prototype ofANA is currently being developed and will be released in 2008: the goal is to demonstrate the feasibility of autonomic networking within the 4 years of the project.

In this paper we propose a self-configuring framework for mobile ad hoc networks (MANETs). Our architecture is based on the degenerated use of network address translation (NAT) where each node locally builds its "private address map", i.e. its own view of the addressing plan of the entire MANET. In contrast to previous schemes, MANET nodes do not need to coordinate in order to generate unique (IP) addresses.

We have built an ad hoc protocol evaluation testbed (APE) in order to perform large-scale, reproducible experiments. APE aims at assessing several different routing protocols in a real-world environment instead of by simulation. We present the APE testbed architecture and report on initial experiments with up to 37 physical nodes that show the reproducibility and scalability of our approach. Several scenario scripts have been written that include strict choreographic instructions to the testers who walk around with ORiNOCO equipped laptops. We introduce a mobility metric called virtual mobility that we use to compare different test runs. This metric is based on the measured signal quality instead of the geometric distance between nodes, hence it reflects how a routing protocol actually perceives the network's dynamics.

We describe a steganographic protocol for packet switched networks that is based on the dynamic rewriting of packet headers. The protocol provides confidentiality without encryption based on Rivest's "chaffing and winnowing" technique ("Chaffing and winnowing", MIT Lab for Computer Science, March 1998). We identify new places in computer networks where this method can be applied and describe an alternative chaffing method that relies on unpredictable number sequences rather than the use of message authentication codes. Our approach requires far less chaffing bandwidth overhead. Moreover, thanks to the underlying active network, we can place packet stream repeaters and filters on intermediate (and untrusted) nodes. Header hopping is closely related to frequency hopping in wireless communications; we also link it to Chaum's work (Communications of the ACM, Feb. 1981) on anonymous routing.

Active networks allow protocol processing code to be loaded dynamically into network nodes at run-time. This code can perform tasks specific to a stream of packets or even a single packet. In this paper we compare two active network architectures: the active node transfer system (ANTS) and the messenger system (M0). We have implemented a robust audio multicast protocol and a layered video multicast protocol with both active network systems. We discuss the differences of the two systems, evaluate architectural strengths and weaknesses, compare the runtime performance, and report practical experience and lessons learned.

Mobile code technology has become a driving force for recent advances in distributed systems. The concept of the mobility of executable code raises major security problems. In this paper, we deal with the protection of mobile code from possibly malicious hosts. We conceptualize the specific cryptographic problems posed by mobile code, and we are able to provide a solution for some of these problems. We present techniques to achieve "non-interactive evaluation with encrypted functions" in certain cases and give a complete solution for this problem in important instances. We further present a way in which an agent might securely perform a cryptographic primitive-digital signing-in an untrusted execution environment. Our results are based on the use of homomorphic encryption schemes and function composition techniques.

Current standard protocol 'stack' architectures are static.The fixed number -for instance -of layers an application can access, or the order in which they must be arranged, exclude a large class of potential cotnmunication protocols.We propose to investigate more flexible protocol stacks consisting of a 'protocol environment' populated by standard communication functionalities.The main ingredient is the ability for an application to compose protocol stacks out of standard protocol entities as well as the downline loading of new protocol entities.This leads to application-tailored, extensible stacks, possibly established at run-time by a bootstrap procedure.Different ways to implement such an environment are discussed, and the current work on a 'toy environment' is presented.