Research Publications Authored by SLIIT Staff

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This collection includes all SLIIT staff publications presented at external conferences and published in external journals. The materials are organized by faculty to facilitate easy retrieval.

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Author: search.filters.author.Nishi, HHas files: Yes

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Now showing 1 - 10 of 26
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    On the effectiveness of using network device state information for network path selection
    (Elsevier, 2018-01-01) Wijekoon, J; Amunugama, D; Nishi, H
    Network path selection defines the methodology of selecting the best routes and forwarding traffic in a network service provider (NSP). NSPs use routing protocols that are optimized for a single arbitrary metric (i.e., administrative weight), which is commonly calculated according to the link state information, to select network paths. Despite the advantages, link-state protocols lack the ability to select network paths by considering the states of network devices such as the effect of routers for network path selection. Apparently, studying possible techniques for selecting network paths based on the state information of network devices, e.g., routers, has become obligatory. This paper studies the effectiveness of using network device state information for network path selection by presenting the Extended Server Link Router state Routing Protocol (ESLR). ESLR uses the state information of network devices as parameters to calculate a composite route metric; ESLR selects the network paths based on the cumulative propagation delay. By simulating ESLR using an ISP topology, the proposed protocol is examined for the effectiveness of using network device state information for network path selection.
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    Previous hop data retransmission service for SoR-based public networks
    (IEEE, 2014-12-22) Tennekoon, R; Wijekoon, J; Harahap, E; Nishi, H
    It is a well-known fact that the Internet traffic travels through public networks and these networks are vulnerable and congested. Whenever an error in a packet is detected, the packet should be retransmitted back to the receiver to reduce/overcome the data loss. Automatic repeat request (ARQ) method is a well-known data retransmission method used by protocols such as Transmission Control Protocol (TCP). This method will retransmit data all the way from the sender resulting higher end-to-end retransmission delays in the packet transmission. Nevertheless this method is widely used and operational, it will also introduce unnecessarily duplicate packets further congesting the networks when it retransmit the entire packet stream from an unacknowledged packet after detecting a retransmission requirement. Encryption and public key cryptography are important technologies that are used to preserve data security and integrity, and to reduce information theft on the public networks. These existing technologies have less flexibility over the current security requirements and the conventional routers are unable to provide end services to the users and applications. To address this need, our laboratory introduced the per-hop data encryption protocol for service-oriented router (SoR) based public networks which allows more secured and flexible method to transfer data over public networks [15]. SoRs are introduced to maintain rich information for the next-generation networks by shifting the current Internet infrastructure to an information-based and an open-innovation platform [6]. SoR is a middleware and can be implemented on a Cisco AXP and Juniper JunosV App Engine where it can analyse all packet stream transactions on its interfaces. Using the features of the SoR, in this paper, we propose a previous hop data retransmission service for public networks. This proposing service can provide higher data availability and reliability to the data that traverses through public networks, reducing the end-to-end data retransmission delays. We implemented a prototype of previous hop data retransmission service on the ns-3 simulator. Furthermore, from the evaluations on the test bed topology, it clearly showed that the proposed method was 80.43% faster than the conventional ARQ based retransmission method.
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    Implement Domain Name System (DNS) on network simulator-3: Implement RFC 1035 on ns-3
    (acm.org, 2016-08-22) Wijekoon, J; Nishi, H
    This paper proposes to implement a domain name system (DNS) module to network simulator-3 (ns-3). The ns-3 is one of the wellknown Internet simulators that provides the ideal simulation environment for network research. Despite its advantages, the ns-3 is not yet possesses a module to simulate DNS, which is an essential module required for Internet-oriented simulations. To this end, this paper implements a DNS module for ns-3 according to the design notes provided in RFC 1035. Moreover, this paper presents the implementation notes of the proposed ns-3 DNS module including its class structures, protocol message structures, name server application development, and host-to-IP resolver development. The proposed ns-3 DNS module is evaluated in terms of host-to-IP mapping, recursive DNS resolution, DNS cache management, and internationalized domain name support.
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    Optimized Service Function Path Selection for IoT Devices Using Virtual Network Function Performance Data
    (IEEE, 2019-01-09) Shanaka, W. A; Abeysiriwardhana, P; Wijekoon, J; Nishi, H
    Software defined networking (SDN) and network function virtualization (NFV) are proposed as software based applications to cater to smart services requirements of smart communities. The services are linked together to support different sets of clients using service function chaining (SFC). Service functions (SFs) in an SFC must be distributed among available computing resources by creating a service function path (SFP) allowing resource management and optimal SF execution. This paper proposes a novel SFP allocation algorithm considering the computation capabilities of hardware resources while minimizing the completion time of SFCs. The proposed algorithm shows 10% performance increment compared to recently developed algorithms such as nearly optimal service function path and optimal service function selection algorithms.
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    Shutter control for cooling air flow management in data center servers
    (IEEE, 2016-10-23) Noguchi, T; Wijekoon, J; Joshi, Y; Yoda, M; Nishi, H
    The growth of energy consumption in data centers is becoming one of the significant problems all over the world. The power usage of IT devices and air-conditioning (AC) units accounts for up to three-quarters of total energy consumption in typical data centers. This study discusses the effectiveness of using shutter-controlled air flow management to control cold air flow into the servers. It can impact the power consumption of both, the servers and the AC units. A raised floor data center has two types of aisles - cold and hot. In most cases, excessive volumes of cold air are pumped into the servers using cold aisles. We are proposing the utilization of a shutter to control the air flow and reduce wastage while preventing damage due to increased CPU temperature. The shutter is intended to control the air flow and maintain the temperature appropriately according to the workload of the servers. We evaluated the proposed system for controlling the flow of air into the servers. The results show that cold air volumes can be reduced by up to 92% while maintaining appropriate control of CPU temperature.
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    On the effectiveness of IP-routable entire-packet encryption service over public networks (november 2018)
    (IEEE, 2018-11-20) Tennekoon, R; Wijekoon, J; Nishi, H
    The Internet is an unsecured public network accessed by approximately half of the world population. There are several techniques, such as cryptography, end-to-end encryption, and tunneling, used to preserve data security and integrity and to reduce information theft. This is because the security of data transmission over public networks is an ever-questionable issue. However, none of the above techniques are capable of providing the flexibility of changing either the algorithm or its key at the intermediary routers according to the requirements of stakeholders, e.g., ISPs or Internet users. Although the transmitted data are encrypted and unreadable, the metadata contained in the packet headers are readable during traversal. Nonetheless, service-based Internet architectures, e.g., IoT architectures, demand the analysis the data streams at the intermediary routers to provide smart services such as strengthening the security of the data streams. To this end, this paper proposes a method to use service-oriented routers for providing secure data transmission by encrypting data packets including the header and trailer information. A prototype of the proposed method is implemented on the ns-3 simulator, and this paper discusses the implementation notes and evaluation of the test results. The test results demonstrate that there is only an average processing cost of 180.14/191.35, 213.96/257.41, 157.56/170.68, and 235.48/ 249.49 μs for encrypting the total encrypted combined packets/total encrypted separate packets using IDEA, DES, AES-GCM, and AES-CTR encryption algorithms, respectively, with a 256-bit key space. This is significantly lower than the tolerable transmission delay (150 ms) defined by the ITU-T.
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    PublicationOpen Access
    Router-based content-aware data redirection for future cdn systems
    (Modern Education and Computer Science Press, 2014-05-01) Wijekoon, J; Harahap, E; Ishida, S; Tennekoon, R; Nishi, H
    Delivery of data-enriched applications has become a top priority on the Internet, and Internet users are demanding faster and higher-quality services. Cater such requirements, Content Delivery Networks (CDNs) were introduced. However, the growth rate of information on the Internet requires infrastructural modifications to keep the consistency while maintaining quality of the Internet services. To this end, the Service-oriented Router is introduced to provide content based services by shifting the current Internet infrastructure to informationbased open innovation platform. In this study, initially we provide implementation notes of a software-designed SoR. Then we propose a new method of CDN Request Redirection (RR) (SoR-based RR), which is designed to redirect packets based on the content of packets and the status of content servers using an SoR as an edge router of a CDN. Furthermore, we present the design and implementation of a prototype to realize the SoR-based RR in a testing network. By analyzing the result of the prototype implementation, we show that the SoR-based RR can enhance the both client experience and faster adaptations to the server changes in CDN environments.
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    PublicationOpen Access
    Slrouting: Server link router state routing protocol design and implementation
    (acm.org, 2015-11-18) Wijekoon, J; Nishi, H
    Packet propagation delay reduction is becoming the primary concern of the Internet. Internet service providers (ISPs) attempt to optimize packet routing to offer the best route to their subscribers by achieving desired network performance. Consequently, a route computation metric that uses packet propagation delay instead of link state will be a strong incentive for ISP routing optimization, in which case ISPs could ensure minimal delay route paths for their subscribers. To this end, we present SLRouting, a novel Interior Gateway Routing Protocol. SLRouting calculates a composite route metric using packet waiting delays of servers and routers as well as the packet propagation delay of network links. SLRouting computes the route matrix by selecting the minimal delay path for destination networks. This paper presents the first version of the SLRouting including its theory, design, and implementation notes. A prototype of the proposed protocol is implemented using the ns-3 simulator, and the results were used to evaluate the proposed protocol.
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    FROG: A packet hop count based DDoS countermeasure in NDN
    (IEEE, 2018-05-25) Nakatsuka, Y; Wijekoon, J; Nishi, H
    Named Data Networking (NDN) is a promising inter-networking paradigm that focus on content rather than hosts and their physical locations. In NDN Consumers issue Interests for Contents. Producers generate a content in response to each received interest and such content is routed back to the requesting consumer. When compared to IP, NDN brings advantages such as better throughput and lower latency, because routers are able to cache popular contents and satisfy interests for such contents locally. However, before being considered a viable approach, NDN should offer security services that are ideally better, but at least equivalent to current mechanisms in IP.In this regard, mechanisms to prevent DDoS are of paramount importance. In this work we propose FROG: a simple yet effective Interest Flooding Attack (IFA) detection and mitigation method. FROG runs on routers that are directly connected to NDN consumers and monitors packet hop counts. It then calculates mean and variance using stored hop counts to distinguish attackers from legitimate users. We use the NDN simulator ndnSIM to evaluate FROG's effectiveness. Our results show that FROG improves resilience against DDoS attacks. In particular, during an attack, legitimate users can still receive 75% of requested contents. Without FROG this number decreases to 50%.
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    Time-series decomposition of power demand data to extract uncertain features
    (IEEE, 2017-05-19) Imanishi, T; Yoshida, M; Wijekoon, J; Nishi, H
    The spread of smart meters means that a large amount of power demand information from private houses is being collected around the world. Owing to the development of smart city infrastructure, the use of standardized frameworks for extracting features from power demand information has become vital. In this paper, we propose a novel decomposition approach useful for extracting feature values from power demand information from a house. Energy consumption was monitored for multiple houses for one month in Japan with a sampling duration of 30 minutes, which is a standard sampling time of smart meters in Japan. First, periodic characteristics were detected for 24 hours based on autocorrelation analysis. Then, the monitored information was decomposed into four components: standby power, trends, and periodic and residual parts. The distribution of the residual part is similar to a Gaussian distribution, so the behavior of the residual part was parameterized using variance and average. Trend, periodic, and residual components were clustered by means of k-means clustering in order to aggregate the difference in behaviors. There was no periodic component in the residual part according to auto-correlation analysis. Nevertheless, some clusters had a relatively large variance, which means that abnormal power demand occurred frequently in datasets. The amount of variance and climate correlation was analyzed, and the fact detected that large scale events disturb usual daily life-styles, from the viewpoint of energy usage. Last, these features were compared with actual customer information. In the evaluation, family structure and floor space were utilized to prove the effectiveness of the proposed decomposition approach. The evaluation proved that this decomposition method could extract uncertainty features from power demand information.