Building a Document-Oriented Warehouse Using NoSQL

The traditional data warehousing approaches should adapt to take into consideration novel needs and data structures. In this context, NoSQL technology is progressively gaining a place in the research and industry domains. This paper proposes an approach for building a NoSQL document-oriented warehouse (DocW). This approach has two methods, namely 1) document warehouse builder and 2) NoSQL-Converter. The first method generates the DocW schema as a galaxy model whereas the second one translates the generated galaxy into a document-oriented NoSQL model. This relies on two types of rules: structure and hierarchical rules. Furthermore, in order to help understanding the textual results of analytical queries on the NoSQL-DocW, the authors define two semantic operators S-Drill-Up and S-Drill-Down to aggregate/expand the terms of query. The implementation of our proposals uses MangoDB and Talend. The experiment uses the medical collection Clef-2007 and two metrics called write request latency and read request latency to evaluate respectively the loading time and the response time to queries.

Design and Implementation of Sequential Read Ahead in Zoned Namespaces for Solid State Drives

In the day and age of data and information, the ability to retrieve the information becomes of paramount importance. The cutting edge technology in terms of data storage is currently Solid State Devices which use NAND gates to store data. This relatively new method of storing data presents numerous avenues of research and breakthroughs. The concept of Zoned Namespaces in SSD firmware is one such major avenue of ongoing research. The objective of this paper is to understand the need for higher data accessing speeds and envisioning the advancements made possible by improving basic read and write speeds in SSD's. The goal is to allow for writing sequential data in namespaces where the data related to each other holds a granularity of a single zone. The idea is achieved by implementing sequential read ahead where the sequential data is read ahead of time by anticipating host read request to that data. This gives the host, cache hit on requested data which greatly improves performance. The pre-fetched data is cleared from cache once the data has been read or any disabling condition occurs thus not hampering normal functioning of the drive. The implementation was tested on a 8 TB form factor SSD. The results for reads were 70 MB/s for ZNS before SRA and 275 MB/s after SRA enablement. Thus a very significant increase is observed which proves that the objective was achieved.

Adding Channel Security to a Fingerprint Verification Chain

Authenticating persons using fingerprints is a widely accepted method in the field of access control, border control, prosecution and many others. Today, fingerprint modules with customizable firmware can be bought commercially off the shelf by hobbyists and small companies to be used in their applications and are usually locally separated from a controller implementing the feature extraction and comparison algorithms. As a matter of fact, the communication channel between the sensor and the controller module is susceptible to eavesdropping and man in the middle attacks. Nevertheless, adding communication channel security to such a system has a direct negative impact on the system’s response time, thus directly affecting user acceptance. The aim of this paper is to provide a comprehensive investigation on measures to counter run-time degredation when adding communication channel security on behalf of an existing fingerprint verification chain. We show that a combination of the elliptic curve Diffie-Hellman key exchange together with AES-256 and the use of parallelization using OpenMP on a controller node leads to an acceptable run time making key creation and exchange upon every fingerprint read request a suitable undertaking.