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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.

Routing messages in a network can be thought of in terms of graphs which allows routing protocols to use well known graph algorithms to determine the best way to reach a given network.

Populating and maintaining the Route Table (and Route Cache) is one of the most critical activities a network engineer performs. Static Routes are one way to populate the table, but Static Routes do not change as the network changes. At first this does not seem like a problem, but even medium–size networks can be too complex to maintain with Static Routes.

Computer–to–computer connections are made by connecting physical media at Layer 1 or the Physical Layer. The problems encountered are well understood and improvements in speed and reliability have removed virtually all problems, other than connector or “wire” problems, from consideration. Once the building wiring is in and tested, it is simply a matter of plugging in jumper cables to build the physical network. To construct a network of any size or complexity, a logical network of shared media and addressable devices must be built on top of the Layer 1 wiring.

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.

Routing in a large ISP requires a different viewpoint than routing in an organization’s network. Large networks need to make use of techniques to summarize routes and often view organization’s networks as nothing more than nodes on their network.

At the Physical Layer, messages consist of bits placed on the media but this technique does not scale to even small–to–moderate size networks. To build a network of any size, the media must be shared between multiple devices rather than dedicated to a single pair of devices. In order to do this, each device must have an address and there must be protocols to insure that each device can eventually send a message with a reasonable chance of that message reaching the correct destination.

Static assignment of names and addresses on a large network can consume a large amount of time and suffers from the same problems as any static configuration. Human errors by the network administrators can lead to duplicate IP addresses, IP addresses in the wrong ranges, and other errors.

It is important to have a consistent physical network for all of the protocols examined in this text for three reasons

Route Interchange Protocol (RIP) is one of the simplest routing protocols and one of the first to be developed. For smaller networks it is the protocol of choice, even though RIP has many drawbacks. RIP is simple to implement, requires very little expertise, and is very common on the Internet.

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.

Enterprise networks are large, complex, and typically organized along enterprise lines. While RIP is fine for smaller networks, at the enterprise level RIP becomes very problematic. In some cases, RIP updates can comprise more than 25% of the network traffic.

Until now the concentration has been on the OSI layers responsible for building the network. The end–points of the data conversation are not responsible for the actual movement of messages but are responsible for the higher level functions to insure that the conversation meets the requirements of the final application. When the conversation is initiated, the details of the functioning of the upper levels are negotiated before data begins to flow.

As stated before, see 2.1, the physical layer has one simple, and extremely important function: to move bits from one NIC to another as quickly as possible. How this is done depends solely upon the media used to connect the two NICs. For copper wiring this is done by varying the voltage between one voltage for a binary “0” and another for a binary “1”. For wireless or fiber similar techniques are used. The speed at which a message can be transmitted is based solely upon how fast one NIC can produce a varying signal that can be correctly interpreted by the other. This speed is measured in terms of raw bits and can vary from a few hundred bps1 to many millions of Bps2.

Modern email grew out of a number of older protocols that were often vendor specific. While many early network OS were able to send short messages, almost none were designed to interoperate with all of the products from the same vendor, let alone between different vendors.

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.

An increasing number of modern automobiles are essentially drive-by-wire systems, highly computerized, and connected wirelessly to services such as OnStar or Toyota Safety Connect. While these features enhance automobile safety and reliability, the security impact is a growing concern. This paper examines the security of drive-by-wire automobile systems. Generic models of access control and information flow are defined, with specific instances of the 2010 Toyota Prius used where appropriate. The automobile systems are examined from the viewpoint of the driver with special emphasis on the driver's ability to determine who, or what, is actually in control of the automobile in critical situations.

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.

In Path Verification, a verifier needs to determine how closely a mobile node's claimed path agrees with its actual path. We design a technique to leverage new or existing static wireless sensor networks to provide witness certificates to allow the verifier to compare actual paths with claimed paths of the vehicle as a notion of curve similarity. This is done by using Continuous Dynamic Time Warping to construct a manifold from the actual and claimed paths. The geodesic distance from the path origins to the path terminations over the surface of this manifold is analogous to the Frechet Distance between the paths. Using simulations and experiments on city streets, we demonstrate the performance of our technique. We also propose lightweight cryptographic techniques to mitigate security attacks.

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.