Hilmi E. Egilmez

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OpenFlow is a programmable network protocol and associated hardware designed to effectively manage and direct traffic by decoupling control and forwarding layers of routing. This paper presents an analytical framework for optimization of forwarding decisions at the control layer to enable dynamic Quality of Service (QoS) over OpenFlow networks and discusses(More)
OpenFlow is a Software Defined Networking (SDN) paradigm that decouples control and data forwarding layers of routing. In this paper, we propose OpenQoS, which is a novel OpenFlow controller design for multimedia delivery with end-to-end Quality of Service (QoS) support. Our approach is based on QoS routing where the routes of multimedia traffic are(More)
This paper introduces a novel spectral anomaly detection method by developing a graph-based filtering framework. In particular, we consider the problem of unsupervised data anomaly detection over wireless sensor networks (WSNs) where sensor measurements are represented as signals on a graph. In our framework, graphs are chosen to capture useful proximity(More)
OpenFlow is a clean-slate Future Internet architecture that decouples control and forwarding layers of routing, which has recently started being deployed throughout the world for research purposes. This paper presents an optimization framework for the OpenFlow controller in order to provide QoS support for scalable video streaming over an OpenFlow network.(More)
This paper presents novel QoS extensions to distributed control plane architectures for multimedia delivery over large-scale, multi-operator Software Defined Networks (SDNs). We foresee that largescale SDNs shall be managed by a distributed control plane consisting of multiple controllers, where each controller performs optimal QoS routing within its domain(More)
The graph Fourier transform (GFT) - adaptive to the signal structures of local pixel blocks - has recently been shown to be a good alternative to fixed transforms, e.g., the Discrete Cosine Transform (DCT), for image coding. However, the majority of proposed GFTs assume an underlying 4-connected graph structure with vertical and horizontal edges only. In(More)
This paper proposes a new Quality of Service (QoS) optimized routing architecture for video streaming over large-scale multi-domain OpenFlow networks managed by a distributed control plane, where each controller performs optimal routing within its domain and shares summarized intra-domain routing data with other controllers to reduce problem dimensionality(More)
The Karhunen-Loeve transform (KLT) is known to be optimal for decorrelating stationary Gaussian processes, and it provides effective transform coding of images. Although the KLT allows efficient representations for such signals, the transform itself is completely data-driven and computationally complex. This paper proposes a new class of transforms called(More)
Multimedia streaming applications have stringent Quality of Service (QoS) requirements which cannot be always met by the best-effort Internet. To provide QoS, several QoS architectures have been explored over last two decades, but none of them has been truly successful and globally implemented. This thesis presents a novel QoS architecture for multimedia(More)
In video coding, motion compensation is an essential tool to obtain residual block signals whose transform coefficients are encoded. This paper proposes novel graph-based transforms (GBTs) for coding inter-predicted residual block signals. Our contribution is twofold: (i) We develop edge adaptive GBTs (EA-GBTs) derived from graphs estimated from residual(More)