CPS-Based Smart Warehouse for Industry 4.0: A Survey of the Underlying Technologies <s> Blockchain-Based Bookkeeping Subsystem <s> As modern vehicle and communication technologies advanced apace, people begin to believe that the Intelligent Transportation System (ITS) would be achievable in one decade. ITS introduces information technology to the transportation infrastructures and aims to improve road safety and traffic efficiency. However, security is still a main concern in vehicular communication systems (VCSs). This can be addressed through secured group broadcast. Therefore, secure key management schemes are considered as a critical technique for network security. In this paper, we propose a framework for providing secure key management within the heterogeneous network. The security managers (SMs) play a key role in the framework by capturing the vehicle departure information, encapsulating block to transport keys and then executing rekeying to vehicles within the same security domain. The first part of this framework is a novel network topology based on a decentralized blockchain structure. The blockchain concept is proposed to simplify the distributed key management in heterogeneous VCS domains. The second part of the framework uses the dynamic transaction collection period to further reduce the key transfer time during vehicles handover. Extensive simulations and analysis show the effectiveness and efficiency of the proposed framework, in which the blockchain structure performs better in term of key transfer time than the structure with a central manager, while the dynamic scheme allows SMs to flexibly fit various traffic levels. <s> BIB001 </s> CPS-Based Smart Warehouse for Industry 4.0: A Survey of the Underlying Technologies <s> Blockchain-Based Bookkeeping Subsystem <s> Blockchain technology enables the creation of a decentralized environment, where transactions and data are not under the control of any third party organization. Any transaction ever completed is recorded in a public ledger in a verifiable and permanent way. Based on the blockchain technology, we propose a global higher education credit platform, named EduCTX. This platform is based on the concept of the European Credit Transfer and Accumulation System (ECTS). It constitutes a globally trusted, decentralized higher education credit, and grading system that can offer a globally unified viewpoint for students and higher education institutions (HEIs), as well as for other potential stakeholders, such as companies, institutions, and organizations. As a proof of concept, we present a prototype implementation of the environment, based on the open-source Ark Blockchain Platform. Based on a globally distributed peer-to-peer network, EduCTX will process, manage, and control ECTX tokens, which represent credits that students gain for completed courses, such as ECTS. HEIs are the peers of the blockchain network. The platform is a first step toward a more transparent and technologically advanced form of higher education systems. The EduCTX platform represents the basis of the EduCTX initiative, which anticipates that various HEIs would join forces in order to create a globally efficient, simplified, and ubiquitous environment in order to avoid language and administrative barriers. Therefore, we invite and encourage HEIs to join the EduCTX initiative and the EduCTX blockchain network. <s> BIB002
Recently, Blockchain technology has been widely employed in many areas such as digital currency  , transportation BIB001 , government  , and education BIB002 due to its features of security, privacy, decentralization, and immutability. A Blockchain is a distributed append-only ledger to store a growing list of transactions. In a smart warehouse, a ledger is needed for bookkeeping. A traditional digital ledger is unsafe concerning malicious modifications. A Blockchain-based bookkeeping subsystem can be the solution to such issue. However, there remain challenges towards building a Blockchain-based bookkeeping subsystem in a smart warehouse. First, Blockchain is publicly accessible by default, which triggers privacy issues for a private warehouse. Second, the current Blockchain-based system only supports low throughput while numerous data can be generated by a smart warehouse.