Bappaditya Jana

Cryptography is an art of science for secret writing as well as secret communication. In cryptography a message is converted to a cipher text by encryption and reverse back to plain text by decryption. Although many cryptographic algorithms are available in symmetric key cryptosystem as well as public key crypto system but still now no efficient algorithms are not available for a secure communications. In public key cryptography, RSA encryption technique is a most popular as well as a stronger encryption technique. But major disadvantage of RSA scheme is large key size which gets more execution time and increases complexity of the computation. In this paper we have analyzed the performance of Artificial Neural Network(ANN) based RSA technique to optimize the execution time of RSA. From simulation results it is shown that neural network based RSA provides better results than Standard RSA scheme.

Cloud Computing is becoming an envisioned paradigm shift in latest IT scenarios. Cloud Computing provides user a centralized virtual environment without any investment of active physical infrastructure. Clients can store data in cloud and run any applications over internet. Cloud computing is a massive pool of services which can provide clients a system as well as a platform, small to big hardware components, virtual operating system based infrastructure and some system management software. But all data transmission in cloud computing now may come in possibilities of threats. So data security in cloud computing is still at big risk in present IT scenario. Although various type of existing cryptographic algorithms for cloud security are performing but still now all these type of algorithms can be partly or fully broken by anyone. So we need a comparatively strong enhanced security algorithm for reliable cloud platform. In our paper we have shown the use of elliptic curve cryptography algorithm in cloud security and we have proposed as a better security model which serves with minimal computational power in cloud computing than other public key cryptosystem like RSA cryptosystem.

During last few decades' most of the commercial transactions transformed to e-Commerce applications. Some of the widely used ways of e-Transactions are Electronic Fund Transfer (EFT), Credit/Debit Cards, Net-banking, e-Wallets, mobile banking. Mostly it has been observed that there is innumerable number of attacks in cashless e-Commerce transactions, where intruders try to manipulate data for evil purpose. Use of cryptographic technique is one of the popular way to avoid such attacks and to prevent cross-site snatching vulnerabilities, insecure permissions, and other possible threats. In this paper we have used a novel technique based on triple Data Encryption Standard (DES) and compared the security level of this method with other frequently used encryption algorithms such as RSA and Hash function and we observed that if we can fix the issues regarding key transfer and process slow down, it will upgrade the overall security level.

Today ensuring security is one of the major concern in cloud environment. Cloud privacy is a one of the tentative issue in cloud computing. As the entire cloud user do not have same demands regarding cloud privacy. Some of the clients are satisfied with current policy where as others are quite concerned about the corresponding privacy. As per the fundamental cloud architecture it is generally deployed via three core service models, namely software as a service, platform as service and infrastructure as a service. But unfortunately these entire delivery services model are vulnerable to a range of security attacks by intelligent intruder. Although government as well as major of the organizations are moving fast towards a secure cloud cryptography offers a wide range of algorithms for cloud security but all these algorithms provide single level encryption. To enhance the security level we have proposed a multilevel security scheme which is more secure than any type of single level encryption. Particularly our technique shows that only authorized user can able to access the cloud data. Our algorithm is fast and safe in both direction such as upload and download of a file. As decryption technique is multilevel so if some data is lost then it is very difficult to decrypt the data.

In recent years Quantum Cryptography gets more attention as well as becomes most promising cryptographic field for faster, effective and more secure communications. Quantum Cryptography is an art of science which overlap quantum properties of light under quantum mechanics on cryptographic task instead of current state of algorithms based on mathematical computing technology. Major algorithms for public key encryption and some digital signature scheme such as RSA, El Gamal cryptosystem, hash function are vulnerable at quantum adversaries. Most of the factoring problem can be broken by Shore's algorithm and quantum computer threatens other hand discrete logarithm problem. Our paper describes why modern cryptography contributes quantum cryptography, security issues and future goals of modern cryptography.

Rapid advancement of Information technology and Communication, VANET(VehicularAd-hoc Networks) has received immence attention from academia, industry and government in all over world. Due to the change of life style, number of Vehicles on roads increases in last few years. Driving of Vahicles has not stopped from being more challenging and dangerous in day to day. Again Road infrastructure are already saturated. Safety distance between two adjacence vehicle and reasonable speed of vehicles are hardly respected. Drivers is going often with lack of enough attention. Tens of thousands of people die and hundreds of thousands get injured in traffic accidents all over the world in each year. So the life or death risk may be must special feature of VANET's. In the traditional networks or other emerging mobile networks, Security and privacy failures usually bring financial losses, where as in VANET, both security and privacy failures could be much more serious life or death risk. So VANET have emerged as an exciting research and application area. In this paper we have tried to discussed about the overview of VANET infrastructure, some applicatons and some sereous technical and security issues to implement an ideal VANET. We have also mentioned some major attacks on VANET. We hope the insight discussed here will help protocol designers and applications engineers to improve the services provided in VANET and assist drivers to make secure techniques.

Now a days the rapid advancement of wireless communication, Cognitive Radio for vehicular Ad Hoc networks has received immense attention from researchers. Due to the ever increasing demand for more radio spectrum, Cognitive Radio Networks is a one of the solution for this crisis. Security is the one of the basic issue to implement a better CRN. CRN is established in a open communication environment that's why CRN are more vulnerable to security threats than wired networks. Black hole attack is one of the most common attack in CR-VANETs. If the Ad-hoc networks are affected by this attack, it not able to perform effectively. In this situation as a consequence the process of any event detection severely affected. The affected nodes can lead to discrepancies in data analysis and hence come with an erroneous report. We have proposed a simple scheme for recognition of malicious node in Black Hole attack in CR-VANET. In our proposed model, we used a Trusty Dynamic Software Agent (TDSA) which are employed for each node in VANETs and shares databases in the memory spaces of the neighboring nodes. We have compared the communication range(R) and distance between two adjacency nodes. Thus we can detect the connectivity of the two nodes and decide the actual alternate path. After recognition of malicious node we change the effected route and an alternate pathway have proposed. and thus we can eliminate black hole attack from CR-VANETs.

The world wide web is a most well known electronic protocol which allows us to perform massive wireless communication like military communication, commercial and other private communication. But there is a tremendous security crisis such that data security, integrity, theft, loss and presence of infected applications for a authentic communication through digital medium that is why research and development on cryptography gets huge importance by every government as well as commercial sector and private sector. There are many robust cryptographic technique already have tested. Elliptic curve cryptography is a one type of public key cryptosystem like RSA, Diffie - Hellman. The main advantage of ECC is that it allows equal security for a smaller key size than the key size used RSA, that is why ECC reduces the processing overhead. This paper represents a brief review with some statistical results on how ECC has becomes the latest trend in the present and future cryptographic scenario.