Papers by Alfan Presekal, S.T
IEEE Access
Cascading effects in the power grid involve an uncontrolled, successive failure of elements. The ... more Cascading effects in the power grid involve an uncontrolled, successive failure of elements. The root cause of such failures is the combined occurrence of multiple, statistically rare events that may result in a blackout. With increasing digitalisation, power systems are vulnerable to emergent cyber threats. Furthermore, such threats are not statistically limited and can simultaneously occur at multiple locations. In the absence of real-world attack information, however, it is imperative to investigate if and how cyber attacks can cause power system cascading failures. Hence, in this work we present a fundamental analysis of the connection between the cascading failure mechanism and cyber security. We hypothesise and demonstrate how cyber attacks on power grids may cause cascading failures and a blackout. To do so, we perform a systematic survey of major historic blackouts caused by physical disturbances, and examine the cascading failure mechanism. Subsequently, we identify critical cyber-physical factors that can activate and influence it. We then infer and discuss how cyber attack vectors can enable these factors to cause and accelerate cascading failures. A synthetic case-study and software-based simulation results prove our hypothesis. This analysis enables future research into cyber resilience of power grids. INDEX TERMS Blackout, cascading failures, cyber attacks, cyber resilience, cyber security.
IEEE Transactions on Smart Grid
IEEE Transactions on Smart Grid
This paper presents our work on analyzing data of provincial economic differences in Indonesia ba... more This paper presents our work on analyzing data of provincial economic differences in Indonesia based on GDP and education. The data were mainly obtained from the website of Indonesia Central Bureau of Statistic（ Badan Pusat Statistik/BPS）. We performed local change analysis toward education level and GDP of all provinces in Indonesia from 2010 to 2015. We classify the provinces into high GDP per capita and low GDP per capita based on the average GDP per capita. From the analysis we gained the highest correlation value of 0.84 of Junior High School at average education level provinces with low GDP
Journal of Advances in Information Technology, 2019
Visualization is very effective when we analyze the time series data. In the paper, we shall illu... more Visualization is very effective when we analyze the time series data. In the paper, we shall illustrate change of the whole trend on time series data as shapes, as well as local changes. The method we used is the statistical shape analysis which can extract separately the Affine and non-Affine transformation parts from the time change deformation. The method is helpful to see a local movement of each landmark data, compared to other neighbors. In the paper, we shall conduct the Indonesia province comparison, concerning the total fertility rate and the education status between 2007 and 2012. From the visualization, we can easily understand the time series changes.
International Journal of Innovative Technology and Exploring Engineering, 2019
Traffic jam is still one of the main problems in Jakarta Indonesia. To encounter this problem, we... more Traffic jam is still one of the main problems in Jakarta Indonesia. To encounter this problem, we proposed system to monitor the road and perform calculation on vehicles speed and road density. To achieve this, we used SSD to detect vehicle traffic on Jakarta’s road which obtained from public IP Camera. The main contribution of this work are utilization of public IP Camera and remote traffic analytics via cloud based artificial intelligence system. As a result, the program can perform monitoring on roads condition in real time. The accuracy of the system in average is 80% with highest accuracy achieved 92% to detect vehicle speed and road density.
E3S Web of Conferences, 2018
UI GreenMetric as sustainability-based university rankings has received a worldwide acceptance si... more UI GreenMetric as sustainability-based university rankings has received a worldwide acceptance since its initiation in 2010. One of the criteria for this ranking is the annual electricity consumption of participating Universities. There are some challenges in evaluating the overall data, i.e. some electricity consumption information is missing or may not accurately represent the real condition. There is various information that can be used to calculate the university rank associated with electricity consumption. On the other hand, some external data sources from World Bank on the annual electricity consumption per capita for every country is highly correlated with the electricity consumption in every University. This paper aims to show our evaluation and prediction of the annual electricity consumption from participating university using regression analysis based on the available data of UI GreenMetric and relevant external information. This is conducted using regression analysis on...
Electronics, 2019
The encryption process for secure voice communication may degrade the speech quality when it is a... more The encryption process for secure voice communication may degrade the speech quality when it is applied to the speech signals before encoding them through a conventional communication system such as GSM or radio trunking. This is because the encryption process usually includes a randomization of the speech signals, and hence, when the speech is decrypted, it may perceptibly be distorted, so satisfactory speech quality for communication is not achieved. To deal with this, we could apply a speech enhancement method to improve the quality of decrypted speech. However, many speech enhancement methods work by assuming noise is present all the time, so the voice activity detector (VAD) is applied to detect the non-speech period to update the noise estimate. Unfortunately, this assumption is not valid for the decrypted speech. Since the encryption process is applied only when speech is detected, distortions from the secure communication system are characteristically different. They exist w...
International Journal of Future Generation Communication and Networking, 2018
LoRaWAN is an access technology coupled with protocol stack specification which is exclusively pr... more LoRaWAN is an access technology coupled with protocol stack specification which is exclusively presented to serve IoT application. IoT application commonly has small data and infrequent transmission. However, the challenge in presenting wireless access technology for IoT lies in its characteristic of massive node deployment and powerconstrained transmission. Among several technologies, LoRaWAN promises the ability to handle massive number of nodes, longer transmission range, lower power consumption, as well as cheaper communication module. This paper presents a performance evaluation of LoRa network in respect to those claims. The performance of the network in term of packet delivery ratio, average energy consumption per transmission and average energy wasted in collision per nodes are investigated. A realistic scenario is considered, and the scalability study is also conducted via computer simulation. The result shows that the performance of LoRa network is highly dependent to the configuration of spreading factor, coding rate, and frequency selection. The performed experiment shows that the limitation inherited from pure ALOHA access strategy can be alleviated by randomizing frequency selection and node-specific optimization to maximize data rate relative to its location (i.e. channel condition) and contention severity.
TELKOMNIKA Indonesian Journal of Electrical Engineering, 2014
Host Identity Protocol (HIP) is a new kind of Internet protocol which has been developed to resol... more Host Identity Protocol (HIP) is a new kind of Internet protocol which has been developed to resolve the existing problems of Internet protocol TCP/IP. As a new protocol HIP provides many advantages compared to TCP/IP such as in the aspect of security and mobility. Unfortunately, the deployability rate of HIP was still low. One of the reason is because particular solution for currently Internet problems already popular and deployed worldwide. In this work we compare the performance of HIP and TCP/IP using several scenarios. Simulations result show that TCP response time in normal condition (zero attack condition) 98,627 ms, while HIP has the response time of 99,711 ms. We also compare the performance of the HIP, TCP/IP, and SSL against the low to medium Denial of Services attack (DoS). In the condition of low to medium DoS attack, the order from best performance are TCP/IP, HIP, and then the worst one is SSL. In the condition of high DoS attack three of them TCP/IP, SSL, and HIP cannot work. Only HIP that implements HIP Firewall with authorization scenarios that are still available for service.
2014 International Conference on Advanced Computer Science and Information System, 2014
Currently there are dozens of internet based applications. Each of these applications can be acce... more Currently there are dozens of internet based applications. Each of these applications can be accessed by their user on the same application layer protocols but different pattern of payloads. For example social network applications like Facebook, Twitter and Google Plus. Each of them can be accessed using HTTPS protocol, but with different payload for each applications. It also possible to access a service in internet by using tunneled protocol, for example Bit Torrent protocol can be tunneled on top HTTP access. These kind of access modes make standard firewalls obsolete to regulate our university internet access control. In this research, we are aiming to prove whether an application layer access control can be developed using Deep Packet Inspection Method. With the deep packet inspection method, it is possible to identify applications based on their application signature. If the application signature can be identified, we can construct more robust rules to regulate university internet access control. We are developing a prototype of application layer access control using several number of free/open source software components. One of these components is Deep Packet Inspection Library - nDPI - which will become our main focus. This research also will explain the way to assemble those software components in order to perform access control functions. We are also performing a test against nDPI payload detection mechanism and the results are reported in this paper.
2013 IEEE International Conference on Computational Intelligence and Cybernetics (CYBERNETICSCOM), 2013
Host Identity Protocol (HIP) a protocol initiated by IETF has big potency to replace existing Int... more Host Identity Protocol (HIP) a protocol initiated by IETF has big potency to replace existing Internet protocol. HIP has potency to solve various existing Internet problem issues such as mobility, multi-homing, interoperability of Internet, and security. Unfortunately, deployment rates of HIP still low. This work tries to propose solution to increase deployment level of HIP by providing multi-level accountability scenarios for the Internet user and incentive scenarios for HIP user. By providing multi-level accountability Internet user can choose privacy level according to their preference. Incentive scenario tries to provide more benefit for HIP user according to user accountability level by providing different contents and services.
2020 IEEE PES Innovative Smart Grid Technologies Europe (ISGT-Europe), 2020
Power system automation and communication standards are spearheading the power system transition ... more Power system automation and communication standards are spearheading the power system transition towards a smart grid. IEC 61850 is one such standard, which is widely used for substation automation and protection. It enables real-time communication and data exchange between critical substation automation and protection devices within digital substations. However, IEC 61850 is not cyber secure. In this paper, we demonstrate the dangerous implications of not securing IEC 61850 standard. Cyber attacks may exploit the vulnerabilities of the Sampled Values (SV) and Generic Object-Oriented Substation Event (GOOSE) protocols of IEC 61850. The cyber attacks may be realised by injecting spoofed SV and GOOSE data frames into the substation communication network at the bay level. We demonstrate that such cyber attacks may lead to obstruction or tripping of multiple protective relays. Coordinated cyber attacks against the protection system in digital substations may cause generation and line disconnections, triggering cascading failures in the power grid. This may eventually result in a partial or complete blackout. The attack model, impact on system dynamics and cascading failures are verified experimentally through a proposed cyber-physical experimental framework that closely resembles real-world conditions within a digital substation, including Intelligent Electronic Devices (IEDs) and protection schemes. It is implemented through Hardware-in-the-Loop (HIL) simulations of commercial relays with a Real-Time Digital Simulator (RTDS).
2019 16th International Conference on Quality in Research (QIR): International Symposium on Electrical and Computer Engineering, 2019
Visualization is very effective when we analyze the big data. When we handle with time series dat... more Visualization is very effective when we analyze the big data. When we handle with time series data for a long period, especially visualization is needed. In the paper, we shall illustrate change of the whole trend on time series data as shapes. The method we used is statistical shape analysis which can extract the Affine and non-Affine transformations from the deformation. The method is also helpful to see a local movement of each data sample, compared to other neighbors. In the paper, we illustrate the whole trend change using the Indonesia province comparison concerning the total fertility rate and the under five mortality rate. From the visualization, we found that the relationship between the data have been relatively stable and shows a linear relationship, finally in 2012.
2018 International Seminar on Research of Information Technology and Intelligent Systems (ISRITI), 2018
This work mainly compares Android Runtime (ART) and Dalvik in the Android-based app. To compare w... more This work mainly compares Android Runtime (ART) and Dalvik in the Android-based app. To compare we create native-based app and test in four version of Android: 4.1 (Jelly Bean), 4.2 (Jelly Bean), 4.4 (Kit Kat), 6.0 (Marshmallow) and 7.0 (Nougat). The test conducted by running three different algorithms which are running on the native-based platform. The algorithms are Quick Sort, Float Calcullation, and Prime Number. The experiment show that native C is better when used in the ART with 59% faster performance compared to Dalvik.
This paper presents our work on analyzing data of provincial economic differences in Indonesia ba... more This paper presents our work on analyzing data of provincial economic differences in Indonesia based on GDP and education. The data were mainly obtained from the website of Indonesia Central Bureau of Statistic (Badan Pusat Statistik/BPS). We performed local change analysis toward education level and GDP of all provinces in Indonesia from 2010 to 2015. We classify the provinces into high GDP per capita and low GDP per capita based on the average GDP per capita. From the analysis we gained the highest correlation value of 0.84 of Junior High School at average education level provinces with low GDP.
2018 International Electronics Symposium on Knowledge Creation and Intelligent Computing (IES-KCIC), 2018
This paper presents our work on analyzing provincial economic differences in Indonesia based on e... more This paper presents our work on analyzing provincial economic differences in Indonesia based on economic indicators. The data were obtained from the official website of Indonesian Central Bureau of Statistics (Badan Pusat Statistik Indonesia). In this paper, we analyzed the provinces Gross Domestic Product (GDP), Per Capita GDP, and GDP/Electricity. We conduct the statistical shape analysis to data of 33 provinces in a time series from the year 2011 to 2015. The total change trend is homogenization. However we found that DKI Jakarta has been grown the Per Capita GDP values especially, compared to the other provinces.
2017 IEEE International Conference on Cybernetics and Computational Intelligence (CyberneticsCom), 2017
The growth of internet has shown the limitation TCP/IP architecture and has enforced the practiti... more The growth of internet has shown the limitation TCP/IP architecture and has enforced the practitioners to invent a new architecture that are more capable to support large scale implementation of content based distribution. Today, Named Data Networking (NDN) has become a breakthrough alternative solution and a potential choice for next generation internet architecture. In this paper, we perform investigation to which extend existing forwarding strategies capable to support context information networking and increase service quality. We test this scenario to handle various types of user applications such as VoIP, multimedia streaming, and widely used application data delivery protocols, with specific requests (contexts), then find out which parts of the app prerequisites are consistent with the current strategy. We used NS3 with ndnSIM 2.0 to simulate and evaluate. This research mainly focused on the implementation of HTTP protocol alongside with the NDN. The experiment results show t...
Uploads
Papers by Alfan Presekal, S.T