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Large Flows Detection, Marking, and Mitigation based on sFlow Standard in SDN
Afaq, Muhammad,Rehman, Shafqat,Song, Wang-Cheol Korea Multimedia Society 2015 멀티미디어학회논문지 Vol.18 No.2
Despite the fact that traffic engineering techniques have been comprehensively utilized in the past to enhance the performance of communication networks, the distinctive characteristics of Software Defined Networking (SDN) demand new traffic engineering techniques for better traffic control and management. Considering the behavior of traffic, large flows normally carry out transfers of large blocks of data and are naturally packet latency insensitive. However, small flows are often latency-sensitive. Without intelligent traffic engineering, these small flows may be blocked in the same queue behind megabytes of file transfer traffic. So it is very important to identify large flows for different applications. In the scope of this paper, we present an approach to detect large flows in real-time without even a short delay. After the detection of large flows, the next problem is how to control these large flows effectively and prevent network jam. In order to address this issue, we propose an approach in which when the controller is enabled, the large flow is mitigated the moment it hits the predefined threshold value in the control application. This real-time detection, marking, and controlling of large flows will assure an optimize usage of an overall network.
A Novel Framework for Resource Orchestration in OpenStack Cloud Platform
( Afaq Muhammad ),( Wang-cheol Song ) 한국인터넷정보학회 2018 KSII Transactions on Internet and Information Syst Vol.12 No.11
This work is mainly focused on two major topics in cloud platforms by using OpenStack as a case study: management and provisioning of resources to meet the requirements of a service demanded by remote end-user and relocation of virtual machines (VMs) requests to offload the encumbered compute nodes. The general framework architecture contains two subsystems: 1) An orchestrator that allows to systematize provisioning and resource management in OpenStack, and 2) A resource utilization based subsystem for vibrant VM relocation in OpenStack. The suggested orchestrator provisions and manages resources by: 1) manipulating application program interfaces (APIs) delivered by the cloud supplier in order to allocate/control/manage storage and compute resources; 2) interrelating with software-defined networking (SDN) controller to acquire the details of the accessible resources, and training the variations/rules to manage the network based on the requirements of cloud service. For resource provisioning, an algorithm is suggested, which provisions resources on the basis of unused resources in a pool of VMs. A sub-system is suggested for VM relocation in a cloud computing platform. The framework decides the proposed overload recognition, VM allocation algorithms for VM relocation in clouds and VM selection.
Distributed SDN Based Network State Aware Architecture for Flying Ad-hoc Network
Muhammad Saqib,Asif Mehmood,Adeel Rafiq,Afaq Muhammad,Wang-Cheol SONG 한국통신학회 2020 한국통신학회 APNOMS Vol.2020 No.09
Flying networks are resource constraints while the nature of nodes’ mobility is very dynamic and unpredicted. Therefore, these networks are very prone to link failure and performance degradation. By considering the existing limitations, this work proposes a new approach consists of proactive and reactive network failure mitigation techniques that have been named as a hybrid approach. In the proposed architecture, the SDN controllers are distributed where each one controls its local domain nodes. The controller node continuously monitors the network state information and proactively adjusts the near-future changes to the topology. Each local domain also contains a sink node that directly connects to the controller. The sink node is used to forward the network state information to the controller and keep the controller defined flow rules for local domain nodes. The sink node can also request a new path in case of any link failure or any topology updates cause by nodes’ movement. Besides, a distributed routing protocol also runs on domain nodes to establish connectivity toward the sink node.
Muhammad Afaq Javed,Muhammad Irfan,Sumera Khalid,Yulong Chen,Saeed Ahmed 대한토목학회 2016 KSCE Journal of Civil Engineering Vol.20 No.7
In recent years, Fiber Reinforced Polymers (FRP) have emerged as useful materials for structural strengthening and rehabilitation. The main aspire of this research is towards evaluating the efficiency of Carbon Fiber Reinforced Polymers (CFRP) in enhancing the shear strength of deep beams. The research work included construction and testing of eight (08) reinforced concrete deep beams. Two of the beams, designated as control beams, were without any shear reinforcement. Remaining six beams were divided into three groups, with each group having two identical beams. Beams in one of these groups were strengthened with conventional type of steel web reinforcement. Remaining two groups were strengthened externally by CFRP sheets with different orientations of CFRP. Magnitude of load causing shear cracks to initiate, and the failure load of each beam was recorded. Significant increase in overall load carrying capacities was observed with both CFRP sheets and web steel reinforcement. CFRP was found to be considerably effective in delaying the initial appearance of shear cracks, thereby improving the serviceability limit state of beams. Beams with CFRP orientation perpendicular to the shear cracks showed higher increment in shear strength. In conclusion, CFRP laminates could effectively be used to strengthen existing RC structures deficient in shear strength, and also to reduce/replace internal steel web reinforcement in new RC structures. Material cost comparison of CFRP reinforced beams with conventional web reinforcement is presented, and the general cost effectiveness of structural rehabilitation by means of CFRP is also discussed.