---

Authenticated Encryption is a block cipher mode of operation which simultaneously provides confidentiality, integrity, and authenticity assurances on the data transmition. In this regard in 2014 CAESAR competition started which aims at finding authenticated encryption schemes that offer advantages over AES-GCM and are suitable for widespread adoption. This paper provides an easy-to-grasp overview over functional aspects, security parameters, and robustness offerings of the CAESAR candidates, clustered by their underlying designs (block-cipher-, stream-cipher-, permutation-/sponge-, compression-function-based, dedicated) and compares encryption/decryption speed of all CAESAR candidates implemented on three processors of three different architectures  AMD64, armeabi and  mipso32.

---

In this paper, the image steganography based on LSB and pixel classification is reviewed. Then, the method for steganography information in image is presented. This method based on LSB. Our purpose of this paper is to minimize the changes in cover image. At the first, the pixels of the image are selected to hiding the message; second complemented message will be hidden in LSB of selected pixels. In this paper, to solve some problems LSB method and minimize the changes, pixels categorized based on values of bits of second, third, fourth. In each category, ratio of changed pixels to unchanged pixels is calculated. If the ratio is greater than one, the LSB of that category are reversed and those changes reach at least. Mean Square Error and Peak Signal to Noise Ratio are two criterions to evaluate stego-image quality. PSNR and MSE of proposed method in comparison with simple LSB method, are respectively growth rate 0.13 percent and reduction rate 0.19 percent.

---

With the emergence of new phenomena in the telecommunications and information technology fields, such as cloud computing and smart networks, we are witnessing new challenges in these areas. One of the most significant challenges is the privacy of outsourced data. Due to the limited processing power of new intelligent devices such as tablets and mobile phones, outsourcing computations to these platforms has gained more attention from users. In addition to data privacy, the security of algorithms used in online software is also of great importance. Therefore, software providers may be concerned about the disclosure of their algorithms after outsourcing them to cloud environments. Existing homomorphic encryption systems can provide privacy for data that needs to be processed online. However, the concurrent privacy of algorithms in these systems has not been addressed. To address this, we introduce a simultaneous homomorphic encryption of data and function called SHDF. This system can homomorphically encrypt all algorithms used in the software and the data to be processed on them, enabling necessary computations to be performed on an insecure server. Furthermore, we show that the proposed system is provably secure. Our implementation results indicate that it is usable in cloud environments with the desired efficiency.