Salim Eryigit

Bio: Salim Eryigit is an academic researcher. The author has contributed to research in topics: Wireless network & Handover. The author has an hindex of 1, co-authored 1 publications receiving 13 citations.

Unsticking the Wi-Fi Client: Smarter Decisions Using a Software Defined Wireless Solution

Abstract: This paper presents a novel software-defined wireless network architecture that integrates coordination mechanisms to enhance the capabilities of a set of central managed Wi-Fi access points (APs). The global architecture is presented in detail, where the handoff mechanism is integrated with a set of active and passive monitoring tools and other functionalities, resulting in a solution that is able to provide smart functionalities using low-cost commercial APs. The framework includes a central controller that has all the information available, and is therefore able to make smart decisions about the assignment of clients to APs. This avoids the problem of the “sticky client” that remains connected to the original AP it is associated with, rather than moving to a nearby AP, which would be a better choice. Two different test scenarios are used to compare a proactive and a reactive handoff mechanism in realistic conditions, with different walking speeds. The results illustrate the advantage of the proactive handoff, as it is more scalable and allows a better integration with other functionalities such as load balancing. The delay incurred by the handoff between APs in different channels is measured with three wireless devices, using five values for the inter-beacon time, proving that fast and seamless handoffs are possible in the scenario. The paper shows that these advanced functionalities, usually available in proprietary solutions, can also be achieved using off-the-shelf equipment.

OpenSDWN: Programmatic Control overHome and Enterprise WiFi

Abstract: The quickly growing demand for wireless networks and the numerous application-specific requirements stand in stark contrast to today’s inflexible management and operation of WiFi networks. In this paper, we present and evaluate OPENSDWN, a novel WiFi architecture based on an SDN/NFV approach. OPENSDWN exploits datapath programmability to enable service differentiation and fine-grained transmission control, facilitating the prioritization of critical applications. OPENSDWN implements per-client virtual access points and per-client virtual middleboxes, to render network functions more flexible and support mobility and seamless migration. OPENSDWN can also be used to out-source the control over the home network to a participatory interface or to an Internet Service Provider.

Wi-5: A Programming Architecture for Unlicensed Frequency Bands

Abstract: We present Wi-5, a spectrum programming architecture for radio resource management in unlicensed frequency bands. It introduces a spectrum control plane that offers fine grained allocation of radio resources, flexible configuration of radio and wireless networking parameters, and continuous monitoring of the wireless network status. These features, along with the centralized nature of this architecture, can effectively address spectrum congestion which often occurs in unlicensed frequency bands. To demonstrate Wi-5's capabilities, we show results obtained from emulating various use case scenarios on our open source proof-of-concept.

Network-Cloud Slicing Definitions for Wi-Fi Sharing Systems to Enhance 5G Ultra Dense Network Capabilities

Abstract: Ultradense Networks (UDNs) seek to scale the 5th-Generation mobile network systems at unforeseen amounts of networks, users, and mobile traffic. We believe that the Wi-Fi sharing service is an asset in expanding 5G UDN capacity requirements for higher coverage and ubiquitous wireless broadband connectivity. However, the limitations of the Wi-Fi sharing pioneer deployment, along with other related works, has led our team to carry out further research. As a result, it was found that FOg CloUd Slicing for Wi-Fi sharing (FOCUS) is a suitable means of expanding 5G UDN capacities. FOCUS applies end-to-end Network-Cloud slice definitions on top of the Wi-Fi sharing technology, with the aim of offering multitenancy and multiservice support for a wide range of services, while meeting carrier-grade requirements and resource control at runtime and making full use of a “softwarized” approach. The feasibility of the FOCUS system is assessed in a real testbed deployment prototype, which allows an accurate view to be obtained of the basic functional principles and system-level proof-of-concept alongside the FON de facto Wi-Fi sharing service. The results suggest that FOCUS offers much greater benefits than FON, owing to its capacity to provide end-to-end Network-Cloud Slices while ensuring independent/isolated service delivery with resource adaptation at runtime.

A Review on Design and Implementation of Software-Defined WLANs

Abstract: Wireless local area networks (WLANs) being the most common access technology, the use of software-defined networks (SDN) in WLANs is inevitable as SDN paradigm has been widely accepted and implemented in the networking industry. Currently, the main focus of SDN is on wired networks. OpenFlow, the most widely accepted protocol for SDN, does not fully support wireless medium, and thus, software-defined WLANs (SDWLANs) have not gained enough attention from the research community. We believe that SDN cannot only solve the long-existing issues for WLANs, but also enable researchers to bring more advanced techniques for higher data rates, better security, and quality of experience. In this article, we have emphasized the importance of integrating SDN into WLANs, and the benefits WLANs can gain by adopting SDN. More specifically, we have explained the advantages as well as the implementation details of SDN for WLANs along with the most prominent recent research efforts and contributions.