This article proposes bit flipping method to conceal secret data in the original image. Here a block consists of 2 pixels and thereby flipping one or two LSBs of the pixels to hide secret information in it. It exists in two variants. Variant-1 and Variant-2 both use 7th and 8th bit of a pixel to conceal the secret data. Variant-1 hides 3 bits per a pair of pixels and the Variant-2 hides 4 bits per a pair of pixels. Our proposed method notably raises the capacity as well as bits per pixel that can be hidden in the image compared to existing bit flipping method. The image steganographic parameters such as, Peak Signal to Noise Ratio (PSNR), hiding capacity, and the Quality Index (Q.I) of the proposed techniques has been compared with the results of the existing bit flipping technique and some of the state of art article.

<p class="PreformattedText">Software evolution is one of the challenging issues in today’s business environment. It is necessary for the organizations, which make use of Information, and Communication Technologies will have to align their business processes to compete with global business. The existing large software systems (“legacy” systems) have never been built to cope with the current business requirement for their poor coding, design structures, logic and documentation. Moreover, Legacy applications have various problems such as lack of up to-date documentation, skilled man power, resources of the Legacy applications, and high maintenance costs. Even though the Legacy system is obsolete, it contains detailed business rules and in continuous use, because it satisfies the users' needs and forms the backbone of the information flow of organization. One of the possible solutions is to refactor or modernize those systems into a new platform. It is necessary to analyse the existing legacy system for better understanding the business logic and its functionalities. This paper analyses various techniques proposed for understanding Legacy systems in existence.</p>

<div><table cellspacing="0" cellpadding="0" align="left"><tbody><tr><td align="left" valign="top"><p>Over the last decade, researchers had  proposed numerous  mobile ad hoc routing protocols for which are operate in an on-demand way, as standard on-demand routing protocols such as AODV, DSR and TORA, etc., have been shown to often have faster reaction time and  lower overhead than proactive protocols. However, the openness of the routing environment and the absence of centralized system and infrastructure make them exposed to security attacks in large extent.  In particular, one such kind of attacks is rushing attack, which is mostly hard to detect due to their inherited properties, that alters the network statistics radically. In this paper, we modeled a rushing attack which is a powerful attack that exploits the weaknesses of the secure routing protocols. Moreover, to know the weakness and strength of these protocols, it is necessary to test their performance in hostile environments. Subsequently, the performance is measured with the various metrics, some ot them are average throughput, packet delivery ratio, average end-to-end delay and etc., to compare and evaluate their performance.</p></td></tr></tbody></table></div>

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The Internet of Things (IoT) has become a significant technology on the internet with its widespread adoption in almost every place we could think of, like homes, hospitals, industries, companies, and so on. This adoption in virtually every device had made them smart, thereby reducing the human intervention to handle them. These devices become smart by gathering the sensed information and communicating with other devices or servers to take the appropriate decisions based on acquired data. However, these devices are deployed in batches with default usernames and passwords, making them vulnerable to attacks as seen in recent pasts like the Mirai botnet attack. Most of the attacks could have been avoided if these devices were equipped with a decent lightweight secure authentication scheme. One of the most common authentication procedures is using traditional public key infrastructure (PKI), which suffers from a single point of failure. Moreover, the complex procedures of PKI make them unfit for low-powered IoT devices. Identity-based cryptography (IBC), a lightweight cryptosystem, could be a good fit for these devices. But, even IBC suffers from a single point of failure and key escrow problem because of the private key generator (PKG). Blockchain has proved its mettle in eliminating a single point of failure with its robust distributed ledger technology. This article presents a novel authentication scheme for IoT devices based on identity-based cryptography using a blockchain network. Blockchain is used as a distributed PKG, eliminating a single point of failure and key escrow problem of PKGs. Further, the proposed work is implemented in Hyperledger Fabric, which is an open-source blockchain platform that efficiently performs the addition, updating, and deletions operation for effective authentication and communication of IoT devices.