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The most common use of the Internet today is the World Wide Web, or “the web”. Indeed, most people use the terms “the web” and “the Internet” interchangeably. This section will cover how to implement Apache web services and how to handle multiple virtual websites on the same server.

While many people use Name Service and Domain Name Service (DNS) interchangeably, there are major differences between the two. If this were not so, the Internet would be much less stable, more prone to system wide failures, and much less resilient to attack.

Like most modern operating systems Raspbian is controlled by a large number of configuration files. When Raspbian boots it reads these files at various times during initialization. As the files are read Raspbian sets internal flags and sometimes even creates new configuration files to reflect the desired behavior of the OS and therefore the Raspberry Pi.

Securing information flow is essential to methods that must ensure confidentiality, but information-flow disruption is equally important because it points to an integrity vulnerability. A proposed security model addresses both aspects, accounting for cyber-physical systems' unique confidentiality and integrity vulnerabilities.

Due to cost-efficiency and less hands-on management, data owners are outsourcing their data to the cloud which can provide access to the data as a service. However, by outsourcing their data to the cloud, the data owners lose control over their data as the cloud provider becomes a third party service provider. At first, encrypting the data by the owner and then exporting it to the cloud seems to be a good approach. However, there is a potential efficiency problem with the outsourced encrypted data when the data owner revokes some of the users' access privileges. An existing solution to this problem is based on symmetric key encryption scheme but it is not secure when a revoked user rejoins the system with different access privileges to the same data record. In this paper, we propose an efficient and Secure Data Sharing (SDS) framework using homomorphic encryption and proxy re-encryption schemes that prevents the leakage of unauthorized data when a revoked user rejoins the system. We also modify our underlying SDS framework and present a new solution based on the data distribution technique to prevent the information leakage in the case of collusion between a revoked user and the cloud service provider. A comparison of the proposed solution with existing methods is provided in detail. Furthermore, we demonstrate how the existing work can be utilized in our proposed framework to support secure query processing. We provide a detailed security as well as experimental analysis of the proposed framework on Amazon EC2 and highlight its practical value.

The problems involved in securing cyber-physical systems are well known to the critical infrastructure protection community. However, the diversity of cyber-physical systems means that the methods used to analyze system security must often be reinvented. The issues of securing the physical assets of a system, the electronics that control the system and the interfaces between the cyber and physical components of the system require a number of security tools. Of particular interest is preventing an attacker from exploiting nondeducibility-secure information flows to hide an attack or the source of an attack. This potentially enables the attacker to interrupt system availability.

Multiple Security Domains Nondeducibility, MSDND, yields results even when the attack hides important information from electronic monitors and human operators. Because MSDND is based upon modal frames, it is able to analyze the event system as it progresses rather than relying on traces of the system. Not only does it provide results as the system evolves, MSDND can point out attacks designed to be missed in other security models. This work examines information flow disruption attacks such as Stuxnet and formally explains the role that implicit trust in the cyber security of a cyber physical system (CPS) plays in the success of the attack. The fact that the attack hides behind MSDND can be used to help secure the system by modifications to break MSDND and leave the attack nowhere to hide. Modal operators are defined to allow the manipulation of belief and trust states within the model. We show how the attack hides and uses the operator's trust to remain undetected. In fact, trust in the CPS is key to the success of the attack.

Traditional security models partition the security universe into two distinct and completely separate worlds: us and them. This partition is absolute and complete. More complex situations are most commonly treated as sets of increasingly more secure domains. This view is too simplistic for cyber-physical systems. Absolute divisions are conceptually clean, but they do not reflect the real world. Security partitions often overlap, frequently provide for the high level to have complete access to the low level, and are more complex than an impervious wall. We present a model that handles situations where the security domains are complex or the threat space is ill defined. To demonstrate our method, we examine a 'drive by wire' system from both the traditional view and in light of the modern reality. This paper examines the system from the viewpoint of the driver with special emphasis on the driver's inability to determine who, or what, is actually in control of the automobile during critical situations.

Due to cost-efficiency and less hands-on management, data owners are outsourcing their data to the cloud which can provide access to the data as a service. However, by outsourcing their data to the cloud, the data owners lose control over their data as the cloud provider becomes a third party. At first, encrypting the data by the owner and then exporting it to the cloud seems to be a good approach. However, there is a potential efficiency problem with the outsourced encrypted data when the data owner revokes some of the users' access privileges. An existing solution to this problem is based on symmetric key encryption scheme and so it is not secure when a revoked user rejoins the system with different access privileges to the same data record. In this paper, we propose an efficient and Secure Data Sharing (SDS) framework using homomorphic encryption and proxy re-encryption schemes that prevents the leakage of unauthorized data when a revoked user rejoins the system. Our framework is secure under the security definition of Secure Multi-Party Computation (SMC) and also is a generic approach - any additive homomorphic encryption and proxy re-encryption schemes can be used as the underlying sub-routines. In addition, we also modify our underlying Secure Data Sharing (SDS) framework and present a new solution based on the data distribution technique to prevent the information leakage in the case of collusion between a user and the Cloud Service Provider.