Placement of 5G RAN slices in multi-tier open RAN 5G networks with flexible functional splits

Sarıkaya, Egemen
The network slicing concept has gained much attention with the development of software-defined network and network function virtualization technologies, enabling logically isolated networks for different purposes in the same network infrastructure. The virtualization of network functions enables functional split of radio access network functions, which can fulfill different 5G radio access network requirements. Functional split can be expressed as deciding the distribution of radio access network functionalities between the radio unit placed at the edge, the distributed unit placed close to the users, and the central unit placed centrally. In this thesis, we considered the placement of virtualized radio access network functions in a multi-tier 5G radio access network architecture and formulated the problem as a Mixed-Integer Quadratically Constrained Programming, considering different functional split options for each network slice separately. Furthermore, a heuristic approach based on the best fit decreasing strategy, FlexBFDP, is proposed and compared with a state-of-the-art solution existing in the literature. Our experiments with different functional split options showed that flexible functional split utilizes physical network resources and satisfies different network slice requirements better than fixed functional split options. Moreover, our experiments comparing the solutions of the Gurobi solver, FlexBFDP, and the state-of-the-art algorithm showed that FlexBFDP outperforms the state-of-the-art algorithm. Even though two out of three Gurobi solutions outperform FlexBFDP in terms of optimization objective, FlexBFDP is preferable in terms of computation time as it takes less time to find a solution. Our results showed that Gurobi solutions with MIPGap 0.01 and 0.1 perform very similar to each other and achieves up to 21% more objective value compared to the FlexBFDP approach, while FlexBFDP outperforms the solution with MIPGap 1 by up to 26%, and the state-of-the-art by up to 140% when the number of network slice requests increases.


Machine learning algorithms for accurate flow-based network traffic classification: Evaluation and comparison
Soysal, Murat; Schmidt, Şenan Ece (Elsevier BV, 2010-06-01)
The task of network management and monitoring relies on an accurate characterization of network traffic generated by different applications and network protocols. We employ three supervised machine learning (ML) algorithms, Bayesian Networks, Decision Trees and Multilayer Perceptrons for the flow-based classification of six different types of Internet traffic including peer-to-peer (P2P) and content delivery (Akamai) traffic. The dependency of the traffic classification performance on the amount and composi...
Analytical Modelling and Performability Evaluation of Multi-Channel WLANs with Global Failures
Ever, Enver; Kirsal, Yonal; Kirsal-Ever, Yoney; Gemikonakli, Orhan (Agora University of Oradea, 2015-6-23)
Wireless local area networks (WLANs) which are based on IEEE 802.11 standard are used widely in existing local area network configurations. IEEE 802.11 offers multiple non-overlapping channels to increase the capacity of the network. There are strong evidences that WLANs are prone to impairments. In order to improve the quality of service (QoS) and to evaluate the performance of WLANs realistically, the availability of the systems should be considered. This paper studies performability evaluation of a multi...
Performance evaluation of routing protocols in wireless ad hoc networks with service differentiation
Yılmaz, Semra; Koçyiğit, Altan; Erten, Murat; Department of Information Systems (2003)
An ad hoc network is a collection of wireless mobile nodes dynamically forming a temporary network without the use of any fixed network infrastructure or centralized administration. Due to the limitations in the wireless environment, it may be necessary for one mobile host to enlist the aid of other hosts in forwarding a packet to its destination. In order to enable communication within the network, a routing protocol is needed to discover routes between nodes. The primary goal of ad hoc network routing pro...
Network-wide energy efficiency in wireless networks with multiple access points
Ozel, Omur; Uysal, Elif (2013-10-01)
This paper presents a distributed mechanism for improving the overall energy efficiency of a wireless network where users can control their uplink transmit power targeted to the multiple access points in the network. This mechanism lets the network achieve a trade-off between energy efficiency and spectral efficiency through the use of suitably designed utility functions. A user's utility is a function of throughput and average transmission power. Throughput is assumed to be a sigmoidal function of signal-t...
HyFI: Hybrid Flow Initiation in Software Defined Networks
Soltani, Ahmad; Bazlamaçcı, Cüneyt Fehmi (2014-04-03)
Software defined networking (SDN) provides techniques to facilitate the management of computer networks in a centralized and integrated architecture by separating the control plane from the data plane in packet forwarding devices and middleboxes. By creating this abstraction layer, SDN allows control of network middleboxes remotely from a controller point, which is either connected directly (out-of-band control using dedicated links) or indirectly (in-band control using the available data network links) to ...
Citation Formats
E. Sarıkaya, “Placement of 5G RAN slices in multi-tier open RAN 5G networks with flexible functional splits,” M.S. - Master of Science, Middle East Technical University, 2021.