Shehzad Ashraf Chaudhry

Bio: Shehzad Ashraf Chaudhry is an academic researcher from International Islamic University, Islamabad. The author has contributed to research in topics: Authentication & Computer science. The author has an hindex of 29, co-authored 107 publications receiving 2305 citations. Previous affiliations of Shehzad Ashraf Chaudhry include Islamic University & Information Technology University.

Sixth generation (6G)wireless networks: Vision, research activities, challenges and potential solutions

Abstract: The standardization activities of the fifth generation communications are clearly over and deployment has commenced globally. To sustain the competitive edge of wireless networks, industrial and academia synergy have begun to conceptualize the next generation of wireless communication systems (namely, sixth generation, (6G)) aimed at laying the foundation for the stratification of the communication needs of the 2030s. In support of this vision, this study highlights the most promising lines of research from the recent literature in common directions for the 6G project. Its core contribution involves exploring the critical issues and key potential features of 6G communications, including: (i) vision and key features; (ii) challenges and potential solutions; and (iii) research activities. These controversial research topics were profoundly examined in relation to the motivation of their various sub-domains to achieve a precise, concrete, and concise conclusion. Thus, this article will contribute significantly to opening new horizons for future research directions.

An improved and provably secure privacy preserving authentication protocol for SIP

Abstract: Session Initiation Protocol (SIP) has proved to be the integral part and parcel of any multimedia based application or IP-based telephony service that requires signaling. SIP supports HTTP digest based authentication, and is responsible for creating, maintaining and terminating sessions. To guarantee secure SIP based communication, a number of authentication schemes are proposed, typically most of these are based on smart card due to its temper resistance property. Recently Zhang et al. presented an authenticated key agreement scheme for SIP based on elliptic curve cryptography. However Tu et al. (Peer to Peer Netw. Appl 1–8, 2014) finds their scheme to be insecure against user impersonation attack, furthermore they presented an improved scheme and claimed it to be secure against all known attacks. Very recently Farash (Peer to Peer Netw. Appl 1–10, 2014) points out that Tu et al.’s scheme is vulnerable to server impersonation attack, Farash also proposed an improvement on Tu et al.’s scheme. However, our analysis in this paper shows that Tu et al.’s scheme is insecure against server impersonation attack. Further both Tu et al.’s scheme and Farash’s improvement do not protect user’s privacy and are vulnerable to replay and denial of services attacks. In order to cope with these limitations, we have proposed a privacy preserving improved authentication scheme based on ECC. The proposed scheme provides mutual authentication as well as resists all known attacks as mentioned by Tu et al. and Farash.

[서평]「Applied Cryptography」

Abstract: The objective of this paper is to give a comprehensive introduction to applied cryptography with an engineer or computer scientist in mind. The emphasis is on the knowledge needed to create practical systems which supports integrity, confidentiality, or authenticity. Topics covered includes an introduction to the concepts in cryptography, attacks against cryptographic systems, key use and handling, random bit generation, encryption modes, and message authentication codes. Recommendations on algorithms and further reading is given in the end of the paper. This paper should make the reader able to build, understand and evaluate system descriptions and designs based on the cryptographic components described in the paper.

UAV Communications for 5G and Beyond: Recent Advances and Future Trends

Abstract: Providing ubiquitous connectivity to diverse device types is the key challenge for 5G and beyond 5G (B5G). Unmanned aerial vehicles (UAVs) are expected to be an important component of the upcoming wireless networks that can potentially facilitate wireless broadcast and support high rate transmissions. Compared to the communications with fixed infrastructure, UAV has salient attributes, such as flexible deployment, strong line-of-sight (LoS) connection links, and additional design degrees of freedom with the controlled mobility. In this paper, a comprehensive survey on UAV communication towards 5G/B5G wireless networks is presented. We first briefly introduce essential background and the space-air-ground integrated networks, as well as discuss related research challenges faced by the emerging integrated network architecture. We then provide an exhaustive review of various 5G techniques based on UAV platforms, which we categorize by different domains including physical layer, network layer, and joint communication, computing and caching. In addition, a great number of open research problems are outlined and identified as possible future research directions.

Two Birds with One Stone: Two-Factor Authentication with Security Beyond Conventional Bound

Abstract: As the most prevailing two-factor authentication mechanism, smart-card-based password authentication has been a subject of intensive research in the past two decades, and hundreds of this type of schemes have wave upon wave been proposed. In most of these studies, there is no comprehensive and systematical metric available for schemes to be assessed objectively, and the authors present new schemes with assertions of the superior aspects over previous ones, while overlooking dimensions on which their schemes fare poorly. Unsurprisingly, most of them are far from satisfactory—either are found short of important security goals or lack of critical properties, especially being stuck with the security-usability tension. To overcome this issue, in this work we first explicitly define a security model that can accurately capture the practical capabilities of an adversary and then suggest a broad set of twelve properties framed as a systematic methodology for comparative evaluation, allowing schemes to be rated across a common spectrum. As our main contribution, a new scheme is advanced to resolve the various issues arising from user corruption and server compromise, and it is formally proved secure under the harshest adversary model so far. In particular, by integrating “honeywords”, traditionally the purview of system security, with a “fuzzy-verifier”, our scheme hits “two birds”: it not only eliminates the long-standing security-usability conflict that is considered intractable in the literature, but also achieves security guarantees beyond the conventional optimal security bound.