Resource Allocation for Periodic Traffic Demands in WDM Networks

Recent research has clearly established that holding-time-aware routing and wavelength assignment (RWA) schemes lead to significant improvements in resource utilization for scheduled traffic. By exploiting the knowledge of the demand holding times, this thesis proposes new traffic grooming techniques to achieve more efficient resource utilization with the goal of minimizing resources such as bandwidth, wavelength channels, transceivers, and energy consumption. This thesis also introduces a new model, the segmented sliding window model, where a demand may be decomposed into two or more components and each component can be sent separately. This technique is suitable for applications where continuous data transmission is not strictly required such as large file transfers for grid computing. Integer linear program (ILP) formulations and an efficient heuristic are put forward for resource allocation under the proposed segmented sliding window model. It is shown that the proposed model can lead to significantly higher throughput, even over existing holding-time-aware models

Improving performance through topology management and wireless scheduling in military multi-hop radio networks

Thesis (S.M.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 2013.Cataloged from PDF version of thesis.Includes bibliographical references (pages 91-93).We investigate two distinct problems in military radio networking. In the first problem, we study a mobile airborne multi-hop wireless network. The mobility of the nodes leads to dynamic link capacities requiring changes to the topology by adding and removing links. Changes are intended to minimize maximum link load. Mixed integer linear programming is used to periodically find topological modifications resulting in optimal performance. To reduce computation and the rate of changes to the topology, we design and employ heuristic algorithms. We present several such algorithms of differing levels of complexity, and model performance using each. A comparison of the results of each method is given. In the second problem, we study a ground multi-hop wireless network. Scalability is an issue for such ground tactical radio networks, as increasing numbers of nodes and flows compete for the capacity of each link. The introduction of a relay node allows additional routes for traffic flows. Greater benefit is achieved by fixing the relay node at a higher elevation to allow it to broadcast to all other nodes simultaneously, thereby reducing the number of hops packets must travel. We use a combination of linear programming (LP) and novel bounds on the achievable network performance to investigate the benefits of such a relay node. We show that a relay node provides moderate improvement under an all-to-all unicast traffic model and more substantial improvement for broadcast traffic patterns.by Zachary S. Bunting.S.M

Journal of Telecommunications and Information Technology, nr 3

kwartalni

Communication Aware Mobile Robot Teams

The type of scenarios that could benefit from a team of robots that are able to self configure into an ad-hoc multi-hop mobile communication network while completing a task in an unknown environment, range from search and rescue in a partially collapsed building to providing a security perimeter around a region of interest. In this thesis, we present a hybrid system that enables a team of robots to maintain a prescribed end-to-end data rate while moving through a complex unknown environment, in a distributed manner, to complete a specific task. This is achieved by a systematic decomposition of the real-time situational awareness problem into subproblems that can be efficiently solved by distributed optimization. The validity of this approach is demonstrated through multiple simulations and experiments in which the a team of robots is able to accurately map an unknown environment and then transition to complete a traditional situational awareness task. We also present MCTP, a lightweight communication protocol that is specifically designed for use in ad-hoc multi-hop wireless networks composed of low-cost low-power transceivers. This protocol leverages the spatial diversity found in mobile robot teams as well as recently developed robust routing systems designed to minimize the variance of the end-to-end communication link. The combination of the hybrid system and MCTP results in a system that is able to complete a task, with minimal global coordination, while providing near loss-less communication over an ad-hoc multi-hop network created by the members of the team in unknown environments

Energy-efficient Transitional Near-* Computing

Studies have shown that communication networks, devices accessing the Internet, and data centers account for 4.6% of the worldwide electricity consumption. Although data centers, core network equipment, and mobile devices are getting more energy-efficient, the amount of data that is being processed, transferred, and stored is vastly increasing. Recent computer paradigms, such as fog and edge computing, try to improve this situation by processing data near the user, the network, the devices, and the data itself. In this thesis, these trends are summarized under the new term near-* or near-everything computing. Furthermore, a novel paradigm designed to increase the energy efficiency of near-* computing is proposed: transitional computing. It transfers multi-mechanism transitions, a recently developed paradigm for a highly adaptable future Internet, from the field of communication systems to computing systems. Moreover, three types of novel transitions are introduced to achieve gains in energy efficiency in near-* environments, spanning from private Infrastructure-as-a-Service (IaaS) clouds, Software-defined Wireless Networks (SDWNs) at the edge of the network, Disruption-Tolerant Information-Centric Networks (DTN-ICNs) involving mobile devices, sensors, edge devices as well as programmable components on a mobile System-on-a-Chip (SoC). Finally, the novel idea of transitional near-* computing for emergency response applications is presented to assist rescuers and affected persons during an emergency event or a disaster, although connections to cloud services and social networks might be disturbed by network outages, and network bandwidth and battery power of mobile devices might be limited

SDN-based traffic engineering in data centers, Interconnects, and Carrier Networks

Server virtualization and cloud computing have escalated the bandwidth and performance demands on the DCN (data center network). The main challenges in DCN are maximizing network utilization and ensuring fault tolerance to address multiple node-and-link failures. A multitenant and highly dynamic virtualized environment consists of a large number of endstations, leading to a very large number of flows that challenge the scalability of a solution to network throughput maximization. The challenges are scalability, in terms of address learning, forwarding decision convergence, and forwarding state size, as well as flexibility for offloading with VM migration. Geographically distributed data centers are inter-connected through service providers’ carrier network. Service providers offer wide-area network (WAN) connection such as private lines and MPLS circuits between edges of data centers. DC sides of network operators try to maximize the utilization of such defined overlay WAN connection i.e. data center interconnection (DCI), which applies to edges of DC networks. Service provider sides of network operators try to optimize the core of carrier network. Along with the increasing adoption of ROADM, OTN, and packet switching technologies, traditional two-layer IP/MPLS-over-WDM network has evolved into three-layer IP/MPLS-over-OTN-over-DWDM network and once defined overlay topology is now transitioning to dynamic topologies based on on-demand traffic demands. Network operations are thus divided into three physical sub-networks: DCN, overlay DCI, and multi-layer carrier network. Server virtualization, cloud computing and evolving multilayer carrier network challenge traffic engineering to maximize utilization on all physical subnetworks. The emerging software-defined networking (SDN) architecture moves path computation towards a centralized controller, which has global visibility. Carriers indicate a strong preference for SDN to be interoperable between multiple vendors in heterogeneous transport networks. SDN is a natural way to create a unified control plane across multiple administrative divisions. This thesis contributes SDN-based traffic engineering techniques for maximizing network utilization of DCN, DCI, and carrier network. The first part of the thesis focuses on DCN traffic engineering. Traditional forwarding mechanisms using a single path are not able to take advantages of available multiple physical paths. The state-of-the-art MPTCP (Multipath Transmission Control Protocol) solution uses multiple randomly selected paths, but cannot give total aggregated capacity. Moreover, it works as a TCP process, and so does not support other protocols like UDP. To address these issues, this thesis presents a solution using adaptive multipath routing in a Layer-2 network with static (capacity and latency) metrics, which adapts link and path failures. This solution provides innetwork aggregated path capacity to individual flows, as well as scalability and multitenancy, by separating end-station services from the provider’s network. The results demonstrate an improvement of 14% in the worst bisection bandwidth utilization, compared to the MPTCP with 5 sub-flows. The second part of the thesis focuses on DCI traffic engineering. The existing approaches to reservation services provide limited reservation capabilities, e.g. limited connections over links returned by the traceroute over traditional IP-based networks. Moreover, most existing approaches do not address fault tolerance in the event of node or link failures. To address these issues, this thesis presents ECMP-like multipath routing algorithm and forwarding assignment scheme that increase reservation acceptance rate compared to state-of-art reservation frameworks in the WAN-links between data centers, and such reservations can be configured with a limited number of static forwarding rules on switches. Our prototype provides the RESTful web service interface for link-fail event management and re-routes paths for all the affected reservations. In the final part of the thesis, we focused on multi-layer carrier network traffic engineering. New dynamic traffic trends in upper layers (e.g. IP routing) require dynamic configuration of the optical transport to re-direct the traffic, and this in turn requires an integration of multiple administrative control layers. When multiple bandwidth path requests come from different nodes in different layers, a distributed sequential computation cannot optimize the entire network. Most prior research has focused on the two-layer problem, and recent three-layer research studies are limited to the capacity dimensioning problem. In this thesis, we present an optimization model with MILP formulation for dynamic traffic in a three-layer network, especially taking into account the unique technological constraints of the distinct OTN layer. Our experimental results show how unit cost values of different layers affect network cost and parameters in the presence of multiple sets of traffic loads. We also demonstrate the effectiveness of our proposed heuristic approach

Intelligent Circuits and Systems

ICICS-2020 is the third conference initiated by the School of Electronics and Electrical Engineering at Lovely Professional University that explored recent innovations of researchers working for the development of smart and green technologies in the fields of Energy, Electronics, Communications, Computers, and Control. ICICS provides innovators to identify new opportunities for the social and economic benefits of society.　 This conference bridges the gap between academics and R&D institutions, social visionaries, and experts from all strata of society to present their ongoing research activities and foster research relations between them. It provides opportunities for the exchange of new ideas, applications, and experiences in the field of smart technologies and finding global partners for future collaboration. The ICICS-2020 was conducted in two broad categories, Intelligent Circuits & Intelligent Systems and Emerging Technologies in Electrical Engineering

Internet of Things. Information Processing in an Increasingly Connected World

This open access book constitutes the refereed post-conference proceedings of the First IFIP International Cross-Domain Conference on Internet of Things, IFIPIoT 2018, held at the 24th IFIP World Computer Congress, WCC 2018, in Poznan, Poland, in September 2018. The 12 full papers presented were carefully reviewed and selected from 24 submissions. Also included in this volume are 4 WCC 2018 plenary contributions, an invited talk and a position paper from the IFIP domain committee on IoT. The papers cover a wide range of topics from a technology to a business perspective and include among others hardware, software and management aspects, process innovation, privacy, power consumption, architecture, applications

GMPLS-OBS interoperability and routing acalability in internet

The popularization of Internet has turned the telecom world upside down over the last two decades. Network operators, vendors and service providers are being challenged to adapt themselves to Internet requirements in a way to properly serve the huge number of demanding users (residential and business). The Internet (data-oriented network) is supported by an IP packet-switched architecture on top of a circuit-switched, optical-based architecture (voice-oriented network), which results in a complex and rather costly infrastructure to the transport of IP traffic (the dominant traffic nowadays). In such a way, a simple and IP-adapted network architecture is desired. From the transport network perspective, both Generalized Multi-Protocol Label Switching (GMPLS) and Optical Burst Switching (OBS) technologies are part of the set of solutions to progress towards an IP-over-WDM architecture, providing intelligence in the control and management of resources (i.e. GMPLS) as well as a good network resource access and usage (i.e. OBS). The GMPLS framework is the key enabler to orchestrate a unified optical network control and thus reduce network operational expenses (OPEX), while increasing operator's revenues. Simultaneously, the OBS technology is one of the well positioned switching technologies to realize the envisioned IP-over-WDM network architecture, leveraging on the statistical multiplexing of data plane resources to enable sub-wavelength in optical networks. Despite of the GMPLS principle of unified control, little effort has been put on extending it to incorporate the OBS technology and many open questions still remain. From the IP network perspective, the Internet is facing scalability issues as enormous quantities of service instances and devices must be managed. Nowadays, it is believed that the current Internet features and mechanisms cannot cope with the size and dynamics of the Future Internet. Compact Routing is one of the main breakthrough paradigms on the design of a routing system scalable with the Future Internet requirements. It intends to address the fundamental limits of current stretch-1 shortest-path routing in terms of RT scalability (aiming at sub-linear growth). Although "static" compact routing works fine, scaling logarithmically on the number of nodes even in scale-free graphs such as Internet, it does not handle dynamic graphs. Moreover, as multimedia content/services proliferate, the multicast is again under the spotlight as bandwidth efficiency and low RT sizes are desired. However, it makes the problem even worse as more routing entries should be maintained. In a nutshell, the main objective of this thesis in to contribute with fully detailed solutions dealing both with i) GMPLS-OBS control interoperability (Part I), fostering unified control over multiple switching domains and reduce redundancy in IP transport. The proposed solution overcomes every interoperability technology-specific issue as well as it offers (absolute) QoS guarantees overcoming OBS performance issues by making use of the GMPLS traffic-engineering (TE) features. Keys extensions to the GMPLS protocol standards are equally approached; and ii) new compact routing scheme for multicast scenarios, in order to overcome the Future Internet inter-domain routing system scalability problem (Part II). In such a way, the first known name-independent (i.e. topology unaware) compact multicast routing algorithm is proposed. On the other hand, the AnyTraffic Labeled concept is also introduced saving on forwarding entries by sharing a single forwarding entry to unicast and multicast traffic type. Exhaustive simulation campaigns are run in both cases in order to assess the reliability and feasible of the proposals