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Empirically Analyzing Ethereum's Gas Mechanism [article]

Renlord Yang, Toby Murray, Paul Rimba, Udaya Parampalli
2019 arXiv   pre-print
Ethereum's Gas mechanism attempts to set transaction fees in accordance with the computational cost of transaction execution: a cost borne by default by every node on the network to ensure correct smart contract execution. Gas encourages users to author transactions that are efficient to execute and in so doing encourages node diversity, allowing modestly resourced nodes to join and contribute to the security of the network. However, the effectiveness of this scheme relies on Gas costs being
more » ... rectly aligned with observed computational costs in reality. In this work, we performed the first large scale empirical study to understand to what degree this alignment exists in practice, by collecting and analyzing Tera-bytes worth of nanosecond-precision transaction execution traces. Besides confirming potential denial-of-service vectors, our results also shed light on the role of I/O in transaction costs which remains poorly captured by the current Gas cost model. Finally, our results suggest that under the current Gas cost model, nodes with modest computational resources are disadvantaged compared to their better resourced peers, which we identify as an ongoing threat to node diversity and network decentralization.
arXiv:1905.00553v1 fatcat:nr46ezmrmjdhvlk7d34ch4xywu

ASOSIASI LIANA DENGAN TUMBUHAN PENOPANGNYA DI BLOK KOLEKSI TAMAN HUTAN RAYA WAN ABDUL RACHMAN, PROVINSI LAMPUNG

Paul Sukra, Indriyanto Indriyanto, Ceng Asmarahman
2021 JURNAL RIMBA LESTARI  
Citarasa vanili sintetik Jurnal Rimba Lestari Vol. 01, No 01, Mei 2021 (01-11) [9] hanya mengandung salah satu komponen citarasa vanilla, yaitu vanillin atau etil vanilin (Boyce et al., 2003) .  ... 
doi:10.29303/rimbalestari.v1i1.24 fatcat:ccab6k3aj5cfjlqfhcdu4vvzf4

New kids on the block: an analysis of modern blockchains [article]

Luke Anderson, Ralph Holz, Alexander Ponomarev, Paul Rimba, Ingo Weber
2016 arXiv   pre-print
Half a decade after Bitcoin became the first widely used cryptocurrency, blockchains are receiving considerable interest from industry and the research community. Modern blockchains feature services such as name registration and smart contracts. Some employ new forms of consensus, such as proof-of-stake instead of proof-of-work. However, these blockchains are so far relatively poorly investigated, despite the fact that they move considerable assets. In this paper, we explore three
more » ... , modern blockchains---Ethereum, Namecoin, and Peercoin. Our focus is on the features that set them apart from the pure currency use case of Bitcoin. We investigate the blockchains' activity in terms of transactions and usage patterns, identifying some curiosities in the process. For Ethereum, we are mostly interested in the smart contract functionality it offers. We also carry out a brief analysis of issues that are introduced by negligent design of smart contracts. In the case of Namecoin, our focus is how the name registration is used and has developed over time. For Peercoin, we are interested in the use of proof-of-stake, as this consensus algorithm is poorly understood yet used to move considerable value. Finally, we relate the above to the fundamental characteristics of the underlying peer-to-peer networks. We present a crawler for Ethereum and give statistics on the network size. For Peercoin and Namecoin, we identify the relatively small size of the networks and the weak bootstrapping process.
arXiv:1606.06530v1 fatcat:ksiljsfumzccrkwpeaijnzyqj4

Composing Patterns to Construct Secure Systems

Paul Rimba, Liming Zhu, Len Bass, Ihor Kuz, Steve Reeves
2015 2015 11th European Dependable Computing Conference (EDCC)  
Building secure applications requires significant expertise. Secure platforms and security patterns have been proposed to alleviate this problem. However, correctly applying patterns to use platform features is still highly expertisedependent. Patterns are informal and there is a gap between them and platform features. We propose the concept of reusable verified design fragments, which package security patterns and platform features and are verified to provide assurance about their security
more » ... erties. Design fragments can be composed through four primitive tactics. The verification of the composed design against desired security properties is presented in an assurance case. We demonstrate our approach by securing a Continuous Deployment pipeline and show that the tactics are sufficient to compose design fragments into a secure system. Finally, we formally define composition tactics, which are intended to support the development of systems that are secure by construction.
doi:10.1109/edcc.2015.12 dblp:conf/edcc/RimbaZBKR15 fatcat:76kvksgi6ja2daejvdzqtgtqum

BPMashup: Dynamic Execution of RESTful Processes [chapter]

Xiwei Xu, Ingo Weber, Liming Zhu, Yan Liu, Paul Rimba, Qinghua Lu
2013 Lecture Notes in Computer Science  
doi:10.1007/978-3-642-37804-1_50 fatcat:fd75lgy42ralvnlnzrmllbpuja

Empirically Analyzing Ethereum's Gas Mechanism

Renlord Yang, Toby Murray, Paul Rimba, Udaya Parampalli
2019 2019 IEEE European Symposium on Security and Privacy Workshops (EuroS&PW)  
Ethereum's Gas mechanism attempts to set transaction fees in accordance with the computational cost of transaction execution: a cost borne by default by every node on the network to ensure correct smart contract execution. Gas encourages users to author transactions that are efficient to execute and in so doing encourages node diversity, allowing modestly resourced nodes to join and contribute to the security of the network. However, the effectiveness of this scheme relies on Gas costs being
more » ... rectly aligned with observed computational costs in reality. In this work, we performed the first large scale empirical study to understand to what degree this alignment exists in practice, by collecting and analyzing Tera-bytes worth of nanosecond-precision transaction execution traces. Besides confirming potential denial-of-service vectors, our results also shed light on the role of I/O in transaction costs which remains poorly captured by the current Gas cost model. Finally, our results suggest that under the current Gas cost model, nodes with modest computational resources are disadvantaged compared to their better resourced peers, which we identify as an ongoing threat to node diversity and network decentralization.
doi:10.1109/eurospw.2019.00041 dblp:conf/eurosp/YangMRP19 fatcat:mcfo53jovjc55d6kfdcpu7b3le

Regerator: a Registry Generator for Blockchain

An Binh Tran, Xiwei Xu, Ingo Weber, Mark Staples, Paul Rimba
2017 International Conference on Advanced Information Systems Engineering  
A registry is a list of information recorded by a trusted authority. Registries have security requirements for data integrity and availability, and for the ability to connect with other registries. Building registries on a blockchain leverages key properties of blockchains, including data integrity, immutability, and availability. By using a blockchain as uniform infrastructure, different registries can also more easily interact with each other. In this paper, we present a browser-based tool
more » ... the model-driven generation and deployment of registries as smart contracts on blockchain. The tool also generates web-based RESTful APIs and user interfaces to interact with the generated registries. We evaluate the feasibility and transaction costs for this approach using metadata from data.gov.au, stored on a decentralised derivative of CKAN (a web-based open-source data registration system) built on the Ethereum blockchain 3 .
dblp:conf/caise/TranXWSR17 fatcat:qwqqyvukcnce7ewcka5jnqcvlq

Building high assurance secure applications using security patterns for capability-based platforms

Paul Rimba
2013 2013 35th International Conference on Software Engineering (ICSE)  
More detail about the formal portions of this process can be found in Rimba, Zhu, Bass, Kuz and Reeves (2015) . We aim to harden the pipeline with Jenkins being untrusted.  ... 
doi:10.1109/icse.2013.6606727 dblp:conf/icse/Rimba04 fatcat:siskbwuma5bb7naos6ip3nszfy

A Taxonomy of Blockchain-Based Systems for Architecture Design

Xiwei Xu, Ingo Weber, Mark Staples, Liming Zhu, Jan Bosch, Len Bass, Cesare Pautasso, Paul Rimba
2017 2017 IEEE International Conference on Software Architecture (ICSA)  
Blockchain is an emerging technology for decentralised and transactional data sharing across a large network of untrusted participants. It enables new forms of distributed software architectures, where agreement on shared states can be established without trusting a central integration point. A major difficulty for architects designing applications based on blockchain is that the technology has many configurations and variants. Since blockchains are at an early stage, there is little product
more » ... a or reliable technology evaluation available to compare different blockchains. In this paper, we propose how to classify and compare blockchains and blockchain-based systems to assist with the design and assessment of their impact on software architectures. Our taxonomy captures major architectural characteristics of blockchains and the impact of their principal design decisions. This taxonomy is intended to help with important architectural considerations about the performance and quality attributes of blockchain-based systems.
doi:10.1109/icsa.2017.33 dblp:conf/icsa/XuWSZBBPR17 fatcat:ltfrmxye7rg6nluzpaqfdxc63e

Correction to: Quantifying the Cost of Distrust: Comparing Blockchain and Cloud Services for Business Process Execution

Paul Rimba, An Binh Tran, Ingo Weber, Mark Staples, Alexander Ponomarev, Xiwei Xu
2019 Information Systems Frontiers  
Inf Syst Front The online version of the original article can be found at https://doi.org/ 10.1007/s10796-018-9876-1 * Paul Rimba paul.rimba@data61.csiro.au An Binh Tran anbinh.tran@data61.csiro.au  ... 
doi:10.1007/s10796-019-09899-w fatcat:hchja3vu5zf5rgcxox6h26a2iy

Integrated Model-Driven Engineering of Blockchain Applications for Business Processes and Asset Management [article]

Qinghua Lu, An Binh Tran, Ingo Weber, Hugo O'Connor, Paul Rimba, Xiwei Xu, Mark Staples, Liming Zhu, Ross Jeffery
2020 arXiv   pre-print
Blockchain has attracted broad interests to build decentralised applications. Blockchain has attracted broad interests to build decentralised applications. However, developing such applications without introducing vulnerabilities is hard for developers, not the least because the deployed code is immutable and can be called by anyone with access to the network. Model-driven engineering (MDE) helps to reduce those risks, by combining proven code snippets as per the model specification, which is
more » ... sier to understand than source code. Therefore, in this paper, we present an approach for integrated MDE across business processes and asset management (e.g. for settlement). Our approach includes methods for fungible/non-fungible asset registration, escrow for conditional payment, and asset swap. The proposed MDE approach is implemented in a smart contract generation tool called Lorikeet, and evaluated in terms of feasibility, functional correctness, and cost effectiveness.
arXiv:2005.12685v2 fatcat:ed4p3kunzfcfxjfpel5xgmi44i

Antibiotic Prophylaxis Prior to Elective ERCP Does Not Alter Cholangitis Rates or Shorten Hospital Stay: Results of an Observational Prospective Study of 138 Consecutive ERCPS

Theodor Alexandru Voiosu, Andreea Bengus, Andrei Haidar, Mihai Rimbas, Alina Zlate, Paul Balanescu, Andrei Voiosu, Radu Voiosu, Bogdan Mateescu
2014 MAEDICA – a Journal of Clinical Medicine  
The role of prophylactic antibiotherapy prior to elective endoscopic retrograde cholangiopancreatography (ERCP) is unclear. We aimed to determine whether patients receiving systemic antibiotics prior to ERCP had lower morbidity and mortality rates as well as shorter hospitalization compared to patients who did not receive antibiotic prophylaxis. We conducted a prospective study of all patients undergoing ERCP in our unit. Antibiotic use, postERCP cholangitis rates, 30-day mortality and hospital
more » ... stay were studied. Also, bacteriological examination of bile aspirates from these patients was conducted and antibiotic susceptibility was determined for the isolated pathogens. One hundred-thirty eight consecutive ERCPs conducted in our unit in a 9 month period were included. Cholangitis developed in 3 (4.6%) cases in the antibiotics groups and 3 (4%) cases in the control group (p=0.8). Hospital stay did not differ significantly between the two study groups (p=0.58). There was only one procedure-related death which was the result of postERCP pancreatitis in a patient with severe associated illnesses. Bile aspirates showed bacterial growth in 75% of the cases where bile was obtained, with E. coli being the most frequently isolated microorganism. No differences in bacteriological profiles were noted between the two study groups. There seems to be no influence on patient-related outcome of antibiotic prophylaxis prior to elective ERCP.
pmid:25705300 pmcid:PMC4316875 fatcat:erxbrizccbhy5hy24qmefxrkfm

Pemberdayaan Desa Wisata Melalui Pengembangan Wisata Air Terjun Songgo Tuyo di Desa Nogosari Kec. Pacet Kabupaten Mojokerto

Imam Safii, Alfin Fatih, Ashad Abdillah Rosyid, M Afif Zamroni, Hasyim Asy'ari
2020 Engagement: Jurnal Pengabdian Kepada Masyarakat  
Paul Green, Garry and, Hanis, Asset Building Community Development. Mardi. Hutomo & Yatmo, Pemberdayaan Masyarakat Dalam Bidang Ekonomi (Yogyakarta: Adiyana Press, 2000).  ...  Wisata alam rimba lestaripun demikian yaitu dengan memanfaatkan media online.  ... 
doi:10.29062/engagement.v4i1.144 fatcat:rqwnab6bxjgwdk6ciighkzwlla

Tindakan Pemerintah Daerah Memberikan Perlindungan Hukum Terhadap Suku Anak Dalam Yang Mengemis Di Kota Jambi

Latifah Amir, Dhil's Noviades, Netty Netty
2020 Jurnal Sains Sosio Humaniora  
Suku Anak Dalam disingkat dengan SAD merupakan istilah yang diberikan di Provinsi Jambi yang diberikan kepada anak rimba.  ...  Senada dengan Bernard Hagen (1908) dalam Tempo (2002) (dia orang kubu of Sumatra) menyatakan orang rimba sebagai orang pra melayu yang merupakan penduduk asli Sumatra demikian pula Paul Bescrta mengatakan  ...  ORANG RIMBA; adalah sebutan yang digunakan oleh etnik ini yang menyebut dirinya.  ... 
doi:10.22437/jssh.v4i2.11532 fatcat:tjaf7k7fzza2tckw3io6eomzs4

Thanks to Our Reviewers 2020

Administrator Administrator
2020 Journal of Gastrointestinal and Liver Diseases  
Ohya Susumu Pais Raluca Pan Jing Hua Popescu Alina Porr Paul Portincasa Piero Procopet Bogdan Radulescu Amanda Regula Jaroslaw Ribaldone Davide Giuseppe Rimbas Mihai Rodriguez Pinto Eduardo  ... 
doi:10.15403/jgld-3315 fatcat:4gvx725hjfaxfm4i5imovjvcje
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