Identifying malicious nodes in network-coding-based peer-to-peer streaming networks

published or submitted for publicatio

A Model for Access Negotiations in Dynamic Coalitions

The process of negotiating common access states in dynamic coalitions that comprise tens of autonomous domains sharing hundreds of resources is time-consuming and error-prone if performed without the benefit of automated tools. This process is also repetitive since, during the lifetime of a dynamic coalition, member domains must undertake the task of negotiating common access states multiple times as domains leave and new ones join the coalition. To define and verify the correctness of tools for automated negotiation, we develop a formal state-transition model of the process of negotiating a common access state. We extend an existing Role Based Access Control (RBAC) language to illustrate a wide variety of negotiation constraints and present a resolution procedure for verifying the satisfaction of such constraints in the state-transition model

A Method: Fornix Depth Measurement in Ophthalmic Socket

Several methods have been publicized to measure the fornix depth but the error in the measurement makes them inconvenient for the correct diagnosis of fornix depth in the eye. In view of the cruelty of disease the precise method is needed to correctly evaluate the fornix depth measurement. In this report, a novel approach is being addressed, to solve the depth measuring issue with the logical experimental design. The explanation with the proposed hypothesis is described here with the relevant scientific approach, the emphasis of certain advantages of the present invention over the conventional measurement approaches. In this case the diagnosis and the process of diagnosis should be accurate, but in the field of ophthalmology an accurate measurement of fornix depth without committing any error was a challenging task. So far in the development of the measurement of fornix depth is concern. Currently, we discussed a novel method for the measurements of fornix depth in ophthalmic eye, which will be beneficial to get the accurate value, however it was not possible in the previously reported methods. It will have many advantages over the existing methods

Analyzing a higher order q(t)q(t) model and its implications in the late evolution of the Universe using recent observational datasets

In this research paper, we explore a well-motivated parametrization of the time-dependent deceleration parameter, characterized by a cubic form, within the context of late time cosmic acceleration. The current analysis is based on the $f(Q,T)$ gravity theory, by considering the background metric as the homogeneous and isotropic Friedmann Lema\^itre Robertson Walker (FLRW) metric. Investigating the model reveals intriguing features of the late universe. To constrain the model, we use the recent observational datasets, including cosmic chronometer (CC), Supernovae (SNIa), Baryon Acoustic Oscillation (BAO), Cosmic Microwave Background Radiation (CMB), Gamma Ray Burst (GRB), and Quasar (Q) datasets. The joint analysis of these datasets results in tighter constraints for the model parameters, enabling us to discuss both the physical and geometrical aspects of the model. Moreover, we determine the present values of the deceleration parameter ($q_0$), the Hubble parameter ($H_0$), and the transition redshift ($z_t$) from deceleration to acceleration ensuring consistency with some recent results of Planck 2018. Our statistical analysis yields highly improved results, surpassing those obtained in previous investigations. Overall, this study presents valuable insights into the higher order $q(t)$ model and its implications for late-time cosmic acceleration, shedding light on the nature of the late universe

Time valid one-time signature for time-critical multicast data authentication

Abstract-It is challenging to provide authentication to timecritical multicast data, where low end-to-end delay is of crucial importance. Consequently, it requires not only efficient authentication algorithms to minimize computational cost, but also avoidance of buffering packets so that the data can be immediately processed once being presented. Desirable properties for a multicast authentication scheme also include small communication overhead, tolerance to packet loss, and resistance against malicious attacks. In this paper, we propose a novel signature model -Time Valid One-Time Signature (TV-OTS) -to boost the efficiency of regular one-time signature schemes. Based on the TV-OTS model, we design an efficient multicast authentication scheme "TV-HORS" to meet the above needs. TV-HORS combines one-way hash chains with TV-OTS to avoid frequent public key distribution. It provides fast signing/verification and buffering-free data processing, which make it one of the fastest multicast authentication schemes to date in terms of end-to-end computational latency (on the order of microseconds). In addition, TV-HORS has perfect tolerance to packet loss and strong robustness against malicious attacks. The communication overhead of TV-HORS is much smaller than regular OTS schemes, and even smaller than RSA signature. The only drawback of TV-HORS is a relatively large public key of size 8KB to 10KB, depending on parameters

Effect of Preoperative Oral Carbohydrate Fluid on Post Operative Nausea and Vomiting in Laparoscopic Cholecystectomy Patients Under General Anesthesia

Background: Postoperative nausea and vomiting (PONV), an unpleasant complication following anaesthesia and surgery has various components such as nausea, retching and vomiting. Although PONV is usually self-limiting and non-fatal, it often causes substantial patient distress and dissatisfaction, augmenting healthcare costs by delaying discharge from post anaesthesia care units and causing unexpected hospital re-admissions. Different pharmacological and non-pharmacological approaches have been used for preventing PONV. Nonetheless, the most effective prophylactic regime has not been determined. Methods: We conducted a prospective randomised study for evaluation of effect of preoperative oral carbohydrate fluid (GROUP- C) and placebo drink (clear water) (GROUP-P) on PONV in 90 adult patients undergoing laparoscopic cholecystectomy surgery under general anaesthesia. The number of episodes of nausea, retching and vomiting, total requirement of antiemetic dose in 24 hours, pre and postoperative blood glucose levels, patient satisfaction score, VAS score and haemodynamic parameters were recorded in the two groups and statistical analysis was done. Results: Demographic data was comparable between the two groups with respect to age, gender and BMI. The surgical time and intra-abdominal pressures throughout the surgery were similar in the two groups. In our study the pre-induction blood glucose levels were found to be higher in group C and preoperative thirst was found to be less in group P. Both the groups were comparable in terms of number of episodes of PONV, total requirement of anti-emetic dose in 24 hours, patient satisfaction and well-being. VAS score for pain and requirement of analgesic dose was also similar in the two groups. Conclusion: Pre-operative oral monosaccharide carbohydrate fluid does not prevent PONV, alter requirement of antiemetic, patient satisfaction and well-being, VAS score for pain, requirement of analgesic dose in patients undergoing laparoscopic cholecystectomy under general anaesthesia, as compared to placebo drink.

Non-Interactive Hierarchical Pairwise Key Predistribution Scheme with Multi-Level Key Establishment

unpublishe

Scalable security and accounting services for content-based publish/subscribe systems

Content-based publish/subscribe systems offer an interaction scheme that is appropriate for a variety of large scale dynamic applications. However, widespread use of these systems is hindered by a lack of suitable security services. In this paper we present scalable solutions for confidentiality, integrity, and authentication for these systems. We also provide verifiable usagebased accounting services, which are required for e-commerce and e-business applications that use publish/subscribe systems. Our solutions are applicable in a setting where publishers and subscribers may not trust the publish/subscribe infrastructure. Keywords: Publish/subscribe systems, Electronic Commerce, Securit

On the Risks of IBE

Abstract. Identity-based encryption (IBE) techniques promise to solve the key distribution problem for secure email. We argue that before this technology is adopted for the important application of secure email it needs to be critically examined in terms of its benefits and risks. To that end our analysis summarizes the unique benefits of IBE and also the significant assumptions and limitations behind it. We then argue that all of these benefits can be achieved with RSA without any additional assumptions and limitations by developing IB-MKD (Identity Based- Message Key Distribution).