The vehicular ad hoc networks (VANETs) are an example of mobile networks, which utilizes dedicated short-range communication (DSRC) to establish a wireless connection between cars, and their primary purpose is to provide more security and comfort for passengers. These networks utilize wireless communications and vehicular technology to collect and disseminate traffic information, and it is required to be delivered to all vehicles on the network reliably and quickly. One of the major challenges raised in VANETs is that the communication path between the source and destination nodes is disconnected due to the dynamic nature of the nodes in this network, and the reconnection process of nodes through the new path reduces the performance of network. This paper presents a highway routing protocol to overcome some of the challenges of these networks including routing cost, delay, packet delivery rate, and overhead. The NS2 is used for simulation, and the performance of the proposed protocol is compared with the VMaSC-LTE and DBA-MAC protocols. The results of the simulation indicated that the proposed protocol outperforms the other two protocols in terms of delay, packet delivery rate, and routing overhead.

Automatic Image Annotation is a technique or a tool to retrieve content-based and semantic concepts images [1]. In technique, the image content is attached to a set of predefined switches. Content-Based Image Retrieval (CBIR) allows the users to retrieve the images efficiently. The image features are automatically extractable using image processing techniques. In this study, we proposed automatic image annotation using standardized color and texture called MPEG-7. These features include Color Layout Descriptor (CLD) and Scalable Color Descriptor (SCD) for colors and Edge Histogram Descriptor (EHD) for image texture. Moreover, to decrease the scope of color layout descriptor, we used Principal Components Analysis (PCA) and for classification we used Support Vector Machine (SVM). For an input search image, the above mentioned features are extracted and classification by Support Vector Machine and prepared to perform the image annotation. This system also presents the results of the comparison between different features from the MPEG-7 descriptors. The automatic image annotation which is presented in this study is related to TUDarmstadt images. The results confirm that the system is a reliable system which has both short vector length (maximum 400 elements for each image) and high precision of 90 percent.

The present study aimed to present a new classification of routing protocols in vehicular ad hoc networks. Vehicular ad hoc network was already classified into V2V and V2I routing protocols, based on communication architecture. In the present study, they were divided into highway routing and urban routing protocols. Then, all highway routing protocols were studied and evaluated. The organizations and interpretations indicated the weakness and strength of the current protocols in this area, upon which some routes were provided for solving these protocols and other probable problems.

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VANETs are networks of connected intelligent vehicles that can communicate with each other, as well as with infrastructure and fixed roadside equipment. As a result of the lack of fixed infrastructure and open-access environment, security is crucial when sending packets. Secure routing protocols have been proposed for VANETs, but most are focused on authenticating nodes and creating a secure route, without considering confidentiality after the route is created. Using a chain of source keys validated by a one-way function, we have proposed a secure routing protocol called Secure Greedy Highway Routing Protocol (GHRP), which provides increased confidentiality over other protocols. As part of the proposed protocol, the source, destination, and intermediate nodes are authenticated using a hashing chain in the first stage, and in the second stage, one-way hashing has been used to increase data security. In order to resist routing attacks such as black hole attacks, the proposed protocol is based on the GHRP routing protocol. The proposed protocol is simulated using the NS2 simulator, and its performance is compared with that of the SAODV protocol. Based on the simulation results, the proposed protocol performs better than the mentioned protocol in terms of packet delivery rate, overhead, and average end-to-end delay.