No abstract

Now a days as we are seeing that the free space optics is one of the emerging technology used for the replacement of the radio frequency wireless communication, due to their advantages over it like cost, speed, bandwidth, minimum error as well as efficient communication. The quality of services provided by the FSO is far better than the RF communication network. The free space optics is unlicensed band which make it less costly than the licensed band technology. As the atmospheric channel is used for transmission the effects of atmospheric condition effects the communication. In this paper we try to discuss all the modulation schemes which help to improve the performances of the optic system.

In a network whether wireless or wired, a set of protocols which are used to distribute the information through various routes between the nodes are said to be the routing protocols which serves as a majorly vital part of the computer networks. They specify the particular and specific path of information exchange by the sending and receiving of packets. Vehicular ad- hoc networks are quite emerging technologies of today’s era presenting the provision of seamless and uninterrupted communication in the network of mobile nodes in dynamic environment. Routing itself proves to be quite a considerable and crucial challenge where the routing protocol named AODV performs its best by proving itself considerably more efficient. The stated paper focuses on the Performance comparison of the conventional protocols AODV and DSDV where AODV outperforms DSDV and offers better QoS but such conventional protocol proves to be inauspicious in VANET. This paper gives verification of better QoS of cluster based routing protocol CBR over the conventional routing protocols. The Simulation and comparison results have been carried out in Network Simulator NS-2 to briefly elaborate the impact of AODV DSDV and CBR routing protocols on the bases of Throughput, Normalized Routing Load, Control overheads, delay, Jitter and Packet drop ratio as performance metrics.

VANET a vehicular ad-hoc network provides the security to vehicles. To provide security in VANET, we are using Elliptical curve cryptography. In this paper we are going to discuss various techniques of cryptography, the techniques such are Advanced Encryption Standard, Data Encryption Standard, and Triple Data Encryption Standard. These techniques are part of symmetric and asymmetric cryptography. In addition to this there are some attacks which we are discussing in this paper like, masquerade attack, replay attack, insider attack, mutual authentication attack, and parallel session attack. These attacks are on different layer. At the end we are comparing these attacks with each other and compare their quality of services.