Enhancement of a simple user authentication scheme for grid computing

Grid computing means a multiple independent computing, because it is composed of resource nodes not located within a single administrative domain. The goal of grid is to only provide secure grid service resources to legal users. Even though grid computing is more than just a technology to abet high performance computing, it is still have some issues to concerns and cares. One of the issues is security issues. Authentication is important part in grid security. Other process in grid are depends on authentication. The aim of this project is to enhance the method of password based authentication scheme and to get better password based authentication scheme in grid computing environment through its time complexity. In this project, the study is done on the existing grid security infrastructure and existing password based authentication scheme. Password Enable Certificate Free Grid Security Infrastructure (PECF-GSI) and A Simple User Authentication Scheme has been selected as the reference for the enhanced authentication scheme. Comparative study and pre-lab testing on A Simple User Authentication Scheme and PECF-GSI has been done in the research methodology. Finally, the enhanced authentication scheme has been designed, developed and tested based on four time complexity notations that are time for modular multiplication, time for multiplication of a number and an elliptic curve point, time for hashing operation and time for inversion. This project has achieved the aim, the scope and the objectives of the project by showing a good performance in terms of time complexity

GIANT CYSTIC HYGROMA COLLI IN AN ADULT- A RARE CASE REPORT

Cystic hygroma (lymphangioma) is often a benign congenital malformation of the lymphatic system that occurs as a result of sequestration or obstruction of lymphatic vessels. Theselesions are usually discovered in infant or children younger than two years of age.Occurrence in adults is uncommon, and fewer than 100 cases of adult lymphangioma have been reported in the literature (1,2) . The objectives of this case report are to present theclinical history and surgical findings, review of literature and the unique problems encountered in the surgical management of this particular patient

Capacity of Sum-networks for Different Message Alphabets

A sum-network is a directed acyclic network in which all terminal nodes demand the `sum' of the independent information observed at the source nodes. Many characteristics of the well-studied multiple-unicast network communication problem also hold for sum-networks due to a known reduction between instances of these two problems. Our main result is that unlike a multiple unicast network, the coding capacity of a sum-network is dependent on the message alphabet. We demonstrate this using a construction procedure and show that the choice of a message alphabet can reduce the coding capacity of a sum-network from $1$ to close to $0$

On the multiple unicast capacity of 3-source, 3-terminal directed acyclic networks

We consider the multiple unicast problem with three source-terminal pairs over directed acyclic networks with unit-capacity edges. The three $s_i-t_i$ pairs wish to communicate at unit-rate via network coding. The connectivity between the $s_i - t_i$ pairs is quantified by means of a connectivity level vector, $[k_1 k_2 k_3]$ such that there exist $k_i$ edge-disjoint paths between $s_i$ and $t_i$. In this work we attempt to classify networks based on the connectivity level. It can be observed that unit-rate transmission can be supported by routing if $k_i \geq 3$, for all $i = 1, \dots, 3$. In this work, we consider, connectivity level vectors such that $\min_{i = 1, \dots, 3} k_i < 3$. We present either a constructive linear network coding scheme or an instance of a network that cannot support the desired unit-rate requirement, for all such connectivity level vectors except the vector $[1~2~4]$ (and its permutations). The benefits of our schemes extend to networks with higher and potentially different edge capacities. Specifically, our experimental results indicate that for networks where the different source-terminal paths have a significant overlap, our constructive unit-rate schemes can be packed along with routing to provide higher throughput as compared to a pure routing approach.Comment: To appear in the IEEE/ACM Transactions on Networkin