A Dynamic Pricing and Leasing Module for 5G Networks

In this paper, a novel framework for enabling dynamic Policy and Charging Rules in modern 5G multi-tenancy environments is designed and presented. More specifically, adaptive pricing schemes are utilized by MNOs for instantiating tailored slices, when the resources of a Mobile Network Operator (MNO) are insufficient to serve the connected users. A scheme where an MNO seeks and leases additional resources from an Infrastructure Provider (InP) is examined in this paper. Their negotiation is modeled as a Service Level Agreement (SLA) and the dynamic charging rules are implemented as an extension of the 5G Policy Charging Function (PCF). The analytical structure of the proposed architecture as well as all the methods and signals developed for MNO and InP collaboration, are described in the context of this work. Finally, extensive testbed experimentation proves proper functioning of the proposed framework, under both UDP and TCP additional traffic demands. © 2020 IEEE

Fast Spectral Assessment for Handover Decisions in 5G Networks

In this paper, we present a UE-driven light-weight mechanism for fast handover decision and efficient WLAN selection in the context of 5G networks. As the network deployments are expected to be denser and the mobile user will be offered a multitude of alternative short coverage range options to have her mobile traffic served, her roaming decision will be performance critical. While the current 3GPP standardization considers the use of network performance statistics of nearby WLANs for the UE-driven roaming selection to address the uncertainty of the shared wireless medium, their collection and processing inevitably affects the mobile user performance and inserts an accuracy-performance tradeoff. We introduce a spectrum assessment framework, that is based on commercial hardware and open-source software, to evaluate the conditions on the nearby WLANs and let the UE to infer their performance with minimum overhead relying on Duty Cycle evaluation and the RSSI metrics. Our ready-to-be deployed solution leverages the use of off-the-shelf equipment and commercial devices and enables fast decision procedures for the WLAN selection with low collection and processing overhead. We evaluate our mechanism by conducting testbed experiments. The results reveal performance gains in terms of UE's achieved throughput when enabling the proposed framework to infer the spectral WLAN conditions and decide for the AP to roam. © 2019 IEEE

Methodology and tools for measurements on wireless testbeds: The NITOS approach

Since its establishment in 2009, the Network Implementation Testbed using Open Source drivers (NITOS) wireless testbed has been extensively used in several research projects for the experimental evaluation of protocols and algorithms. Collection of accurate measurements is of crucial importance for testbed users, allowing them to both select appropriate topologies for their experiments and assess the performance of their implementations. In this chapter, we describe measurement methodologies and tools used in the NITOS testbed in the context of its involvement in some of these projects. We provide examples demonstrating the utility of these tools for specific experiments. We also explain the challenges posed by the complex wireless medium, summarize lessons learned and outline future plans of NITOS towards an enhanced and more integrated measurement framework. © 2013 Springer-Verlag

A Mechanism for Mobile Data Offloading to Wireless Mesh Networks

As the growth of mobile data traffic places significant strain on cellular networks, plans for exploiting under-utilized network resources become increasingly attractive. In this paper, we propose, design, and evaluate a data offloading architecture, where mobile users are offloaded to mesh networks, which are built and managed by residential users. Such networks are often developed in the context of community networks or, recently, as commercial services. Mobile network operators can lease capacity from these networks and offload traffic to reduce their servicing costs. We introduce an analytical framework that determines the offloading policy, i.e., which mobile users should be offloaded, based on the energy cost induced to the cellular base stations. Accordingly, we design a minimum-cost servicing policy for the mesh networks. Clearly, such architectures are realizable only if the mesh nodes agree with each other to jointly serve the offloaded traffic. To achieve this, we employ the Shapley value rule for dispensing the leasing payment among the mesh nodes. We evaluate this paper by simulating the operation of the LTE-A network, and conducting test bed experiments for the mesh network. The results reveal significant savings for eNBs power consumption and reimbursements for mesh users. © 2002-2012 IEEE

New channel allocation techniques for power efficient WiFi networks

Energy efficiency becomes evergreen than ever before. Over the last few years a significant research in wireless communications, aiming to enhance communications efficiency subject to constraint of power consumption, has given rise to optimization techniques of power control and management in wireless networks. Although the initial target was the utilization of resources in order to exploit communications services, the benefits of this effort, underlying the green perspective, are now opening eyes out to research community for a more green matter of conscience in use of communication equipment and devices. Towards this direction and affected by a green sensitivity in terms of wasting useful resources, we propose a system model for infrastructure WiFi networks aiming to reduce the consumed power, by introducing a scheme for channel allocation to Wireless LANs under energy conserving criteria. ©2010 IEEE

Servicing Inelasticity, Leasing Resources and Pricing in 5G Networks

We consider the problem for mobile network operators (MNOs) of leasing resources, servicing and pricing mobile users, in the context of 5G systems that facilitate the use of software-defined radio access network (SD-RAN) and network function virtualization (NFV) technologies. We study the case where the service capability of a MNO cannot satisfy the total users' demand who are characterized by inelastic behavior against the servicing rate that they experience. The MNO addresses this temporal depletion of its resources and acquires dynamically, through leasing, additional resources from an infrastructure provider (InP) to adequately comply with its mobile users' demand. We model and analyze the interactions among the MNO, and the users, as a Stackelberg game. To model users' inelastic behavior, we use a sigmoid utility function. Furthermore, we show the optimal pricing decisions when MNO's supplying capacity satisfies users' demand. Given an excess on MNO's supplying capacity, we employ the generalized r Lambert function to determine the optimal pricing. When MNO's supplying capacity is not ample, we determine, besides pricing, an approximation of the optimal amount of the additional resources to purchase, given a leasing cost imposed by the InP. An interesting finding shows that the amount of additional resources to be purchased can be larger than the MNO's minimum capacity gap. Simulation and testbed experimentation validate the feasibility of the proposed pricing and leasing scheme and demonstrate its practical application. © 2020 International Federation for Information Processing (IFIP)

TLQAP: A topology and link quality assessment protocol for efficient node allocation on wireless testbeds

In this paper we present Topology and Link Quality Assessment Protocol (TLQAP), which we have implemented as a wireless testbed management framework component, that is used to inspect link quality between wireless testbed nodes and appropriately map them to user experiment requirements. TLQAP is mainly an OSI layer 2 design for fixed location, non RF-isolated wireless testbed deployments, which assesses interconnection topology and link quality by estimating packet delivery ratio (PDR) and transmission delay at each node for all requested channel, rate and transmission power combinations. Moreover, TLQAP builds a measurement history log and creates a channel utilization profile, in the context of each testbed node, for all the nearby testbed-external devices that operate independently in the region and are not under the management framework control. The analysis of this information enables TLQAP to choose the channels that have the highest probability of being free during an experiment. TLQAP OSI layer 2 component has been implemented in the click modular router framework and the controller component has been integrated with OMF management framework for wireless testbeds. To outline TLQAP benefits, we have performed experiments on our ORBIT node testbed and we compare it to an existing application level measuring tool. Copyright 2009 ACM

Flexible cross-technology offloading using SDN

Ultra-dense networks are expected to be the vehicle for better network coverage featuring higher speeds, augmented network capacity and more per cell end-users served. Towards meeting these stiff requirements, cells of varying coverage (pico-/femto-/macro-cells) are being deployed, especially in densely populated urban areas. Considering the high availability of such equipment, as well as the low deployment and maintenance costs of WLAN networks, an ecosystem rich in heterogeneity may assist in extending the overall network capacity, thus enabling throughput-hungry services to be offered over contemporary networks. The solution that is considered in this paper is offloading macro-cell users to the available wireless networks in a geographical area, while meeting their demands for the downlink channel. We model our problem and present an applied framework that facilitates cross-technology offloading. Our solution is making use of Software Defined Networking, thus enabling the very rapid and low latency network switching. We experimentally evaluate and benchmark our framework in a real testbed setup, and present our findings. © 2017 IEEE

C2M: Mobile data offloading to mesh networks

As the unprecedented growth of mobile data traffic places significant strain on cellular networks, alternative plans for exploiting already existing and under-utilized wireless infrastructure, become quite attractive. In this paper, we study cellular-to-mesh (C2M) data offloading for LTE-A cellular mobile users to WiFi mesh networks, which are built and managed collaboratively by users. Such networks are developed in the context of community networks or, recently, as commercial services among residential users. Mobile network operators can lease these mesh networks to offload their traffic and reduce their servicing cost. In this context, we introduce an analytical framework that determines which mobile users should be offloaded, based on the energy cost incurred to the cellular base stations (eNB) for serving their demands. Accordingly, we design a routing policy that the mesh network can employ so as to serve the offloaded traffic with the minimum possible cost. Moreover, the reimbursement offered by the operator should be dispensed to the different mesh users, according to their contribution and added-value significance. We address this issue by employing the Shapley value profit sharing rule, which ensures the participation of the mesh nodes in this joint task. We evaluate our work by simulating the operation of the LTE-A network, and conducting testbed experimentation for the mesh network. The results reveal significant savings for eNBs power consumption and compensation profits for mesh users. © 2014 IEEE

A demonstration of a management tool for assessing channel quality information in wireless testbeds

The gradually growing need for testbed use so as networking algorithms to be validated in real environment, has given rise to optimal utilization of testbed resources. Towards this direction, we present a new management tool that is used for assessing channel quality information in wireless testbed deployments. NITOS Connectivity Tool retrieves data concerning link quality measurements, for providing testbed users with useful information about choosing nodes that occasionally satisfy the requirements (link quality, connectivity) needed, for their experiments. NITOS connectivity tool is a full-fledged managerial tool that exploits testbed utilization by letting testbed users have a complete view about testbed's nodes. This tool allows a more sophisticated way to optimally choose network resources of a testbed. © Institute for Computer Sciences, Social Informatics and Telecommunications Engineering 2011