A REVIEW STUDY ON DISTRIBUTED DATABASE COMMUNICATION 1

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1 A REVIEW STUDY ON DISTRIBUTED DATABASE COMMUNICATION 1 Aneet Kaur, 2 Mrs. Meenakshi Bansal 1 M.tech Student, 2 Assistant Professor Coputer Engineering Departent,Yadavindra College of Engineering, Punjabi University, Patiala ABSTRACT: Distributed database plays a vital role in day to day life because in the present era, business environent is increasing at very fast rate so our basic desire is to get reliable inforation fro any source. Since our database is distributed, eans data is located at different geographical locations and finally helps to easily access our valuable & precious data. We propose a architecture that integrates cloud database services with data integrity and the possibility of executing concurrent operations on encrypted data. It is the solution supporting geographically distributed clients to connect directly to an encrypted cloud database, and to execute the concurrent and the independent operations including those odifying the database structure. Distributed database is the eerging technique which focuses on concurrency control and security issues under this distributed database. The NTRU being fast and secure hashing algorith will provide ore security to the syste, in ters of throughput and processing speed. 1. INTRODUCTION Distributed database plays a iportant role in our daily life, because now a day s business environent is increasing at very fast rate, therefore due to this our basic ai is that the inforation we receive fro any source should be accurate and reliable as per our need, because if the inforation is not reliable than it is useless for the user. As our database is distributed it itself defines that the data is located at the different geographical locations and also helps us to access the reliable and valuable data. In case of noral database we will face the proble of failure at one point eans overall failure but in case of distributed database such kind of proble will not occur. This is because the data is geographically located at ore than one location. If there are the chances of failure at one location we can access the data fro another location. 1.1 Distributed Database Syste A distributed database is defined as a database in which the storage devices are not all connected to a coon processing unit such as CPU, controlled by a distributed database anageent syste. It ay be stored in ultiple coputers, located in the sae physical location or ay be dispersed over the network of interconnected coputers. The distributed database syste consists of the loosely-coupled sites that will share no physical coponents. The syste adinistrators can distribute the collections of data across the ultiple physical locations. A distributed database can reside on the network servers on Internet or on the other copany networks because they store the data across the ultiple coputers, the distributed databases can iprove perforance at end-user worksites. Fig -1.1: Distributed database systes [10] In figure1.1 of distributed database their present three sites with their respective databases, all of these are connected through the eans of coputer network. 4

2 Distributed database has any benefits due to which it is widely used in business organization because ain factor which it includes is perforance. The two processes which ensure that the distributed databases reain up-to-date and current are replication and duplication. 1. Replication: it akes the use of specialized software that looks for changes in the distributive database. A replication process akes all databases look the sae once the changes are identified. This process ay be a coplex and tie-consuing depending on nuber or the size of the distributed databases. It requires a lot of tie and the coputer resources. 2. Duplication: it has less coplexity. It recognizes one database as a aster and then duplicates that database. The duplication process is done at the set tie after hours. This have to ensure that each distributed location have the sae data. In the duplication process, users can change only the aster database. This ensures that local data will not be overwritten. The database systes that run on each site ay have a substantial degree of the utual independence. As the distributed networks becoe ore popular, the need for iproveent in the distributed database anageent systes becoes even ore iportant. 1.2 Distributed Database Design Distributed database design plays the iportant role, because not only of its perforance but also because of its reliability and the efficient way of reducing the overall cost and hence it will act as a saving solution to our proble, as systeatic design can give solution to any probles. The design phase includes two approaches[1] View design - defining the interfaces for end users. Conceptual design - is the process by which the enterprise is exained to deterine entity types and relationships aong these entities. One can possibly divide this process into to related activity group. Distributions design - design the local conceptual scheas by distributing the entities over the sites of the distributed syste. The distribution design activity consists of two steps: Fragentation and Allocation. Physical design - is the process, which aps the local conceptual scheas to the physical storage devices available at the corresponding sites, Observation and onitoring - the results is soe for of feedback, which ay result in backing up to one of the earlier steps in the design. Top down approach: this approach generally follows hierarchical pattern i.e. inforation flows in hierarchy that eans first of all defines the generally used concepts followed by the fraework that we are going to use and then the detail. Botto down approach: this is generally the reverse of the top down approach, instead of defining the fraework, this approach focus on details first then later on deal with the fraework. There are present soe additional factors that are considered under this concept along with these top down and botto down approach [1] Data fragentation: it eans that preparing the fragents of any particular data or we can say data is divided into different parts and each part is processed separately, this technique will iprove the overall perforance with appropriate speed. Fragentation can be done by different ways i.e. horizontally (division is done horizontally with the selection of particular row), vertically (division is done vertically ainly by selecting the relevant colun), ixed (done by using soe operators that can be either union or join relevant to our proble). Data replication: In distributed database as database is distributed at any locations therefore fragents of the data should be there on all the locations, therefore with the help of data replication it becoe easy in deciding that which particular fragent or part of data should be replicated so that it can be replicated at different locations Data allocation: Allocation as the nae itself specifies, allocating or giving the data to all the sites where our data is distributed. Therefore the fragent will be given or distributed aong ultiple sites and then it will be stored, so that it can be used at the tie of need. 1.3 DISTRIBUTED DATABASE SECURITY & CONCURRENCY CONTROL As the technology is growing day by day the probles related to the security of the distributed database syste are also increasing due to which the security becoes an iportant issue. The distributed database has all of the security concerns of a single-site database plus several additional proble areas. We begin our 5

3 investigation with a review of the security eleents coon to all database systes and those issues specific to distributed systes. Soe coonly occurred security probles unique to Distributed Database Manageent Systes are: Centralized or Decentralized Authorization. In developing a distributed database, one of the first questions to answer is where to grant syste access. Bell and Griso outline two strategies: Users are granted syste access at their hoe site/ reote site. Users are granted syste access at their hoe site-success of this strategy depends on reliable counication between the different sites. Since any different sites can grant access, the probability of unauthorized access increases. Users are granted syste access at the reote site-this strategy, while perhaps ore secure, has several disadvantages. Probably the ost glaring is the additional processing overhead required, particularly if the given operation requires the participation of several sites. Preservation of integrity is uch ore difficult in a heterogeneous distributed database than in a hoogeneous one. The hoogeneous distributed database has strong central control and has identical DBMS schea If the nodes in the distributed network are heterogeneous several probles can arise that will threaten the integrity of the distributed data. These inconsistencies can cause probles, particularly with coplex queries that rely on ore than one database Conflict resolution depends on the level of central control. 1.4 REQUIREMENTS OF SECURE DATABASE SYSTEM A secure database ust satisfy the following requireents 1. It ust have physical integrity. 2. It ust have logical integrity. 3. It ust be available when needed. 4. The syste ust have an audit syste. 5. It ust have eleental integrity (accurate data). 6. Access ust be controlled to soe degree depending on the sensitivity of the data. 7. A syste ust be in place to authenticate the users of the syste. 8. Sensitive data ust be protected fro inference. 9. Password authentication for users and roles 10. Soe types of external authentication for users and roles including: 11. Login packet encryption for client-to-server and server-to-server connections The key goal of these requireents is to ensure that data stored in the DBMS is protected fro unauthorized observation or inference, unauthorized odification, and fro inaccurate updates. This can be accoplished by using access controls, concurrency controls, and inference reduction strategies. Concurrency: Concurrency eans that the users access the inforation fro the database concurrently but soeties there arise the proble when two or ore users try to access the sae proble at the sae tie.[3] Therefore concurrency should be controlled that can be done by adopting the proper serialization concept while executing ore than one transaction at the sae tie its necessary to take proper easures to control the concurrency. This concurrency should be controlled, as in distributed database their present different servers that were located at various locations. Server 1 Master Server Server 3 Client1 Client2 Client3 Fig 1.2: Updations in distributed database Suppose if any client update soething on the servers than the inforation will go to the asters and then asters will be responsible to update the contents to the other related servers. This way the whole work proceeds. In this case suppose we have four clients and three servers and client one update soething in one of the three servers then the change should be updated in other three servers. If the updated content is 6

4 not reflected in on other three servers their ay arise the conflict. 1.5 Cloud Database Cloud database anageent syste (CDBMS) is defined as the distributed database that delivers a query service across ultiple distributed database nodes located in the ultiple geographically-distributed data centers, both corporate with the cloud data centers. Database accessible to the clients fro the cloud will be delivered to the users on deand via Internet fro a cloud database provider's servers. Fig-1.3: Cloud Database The cloud databases can use cloud coputing to achieve optiized scaling, high availability and effective resource allocation. While cloud database can be a traditional database such as a MySQL or SQL Server database that has been adopted for the cloud use. Cloud databases can offer significant advantages over their traditional counterparts, includes increased accessibility, autoatic failover and the fast autoated recovery fro the failures, inial investent and potentially have the better perforance. 1.6 Advantages of Distributed Database [9] 1) In the distributed database, data can be stored in the different systes like personal coputers, servers, ainfraes, etc. 2) A user doesn t know where the data is located physically. The Database presents the data to the user as if it were located locally. 3) Database can be accessed over the different networks. 4) Data can be joined and updated fro the different tables which are located on the different achines. 5) Even if the syste fails the integrity of the distributed database is aintained. 6) A distributed database is secure. 1. Banking: For custoer inforation, accounts, and loans, and banking transactions. 2. Airlines: For reservations and schedule inforation. Airlines were aong the first to use databases in a geographically distributed anner - terinals situated around the world accessed the central database syste through phone lines and other data networks. 3. Universities: For student inforation, course registrations, and grades. 4. Credit card transactions: For purchases on credit cards and generation of onthly stateents. 5. Telecounication: For keeping records of calls ade, generating onthly bills, aintaining balances on prepaid calling cards, and storing inforation about the counication networks. 6. Finance: For storing inforation about holdings, sales, and purchases of financial instruents such as stocks and bonds. 7. Sales: For custoer, product, and purchase inforation. 8. Manufacturing: For anageent of supply chain and for tracking production of ites in factories, inventories of ites in warehouses / stores, and orders for ites. 9. Huan resources: For inforation about eployees, salaries, payroll taxes and benefits, and for generation of paychecks. 2. LITERATURE SURVEY Bhullar et al.[2014] [4] Distributed database is the eerging technique that plays an iportant role, in day to day life, so we focus on concurrency control and security issues under this distributed database. In this paper we are going to analyze the NTRU algorith, based Encryption decryption technique for security to Distributed Database Syste. Ferretti et al.[2014] [6] revealed that placing critical data in the hands of a cloud provider should coe with guarantee of security and availability for data at rest, and in otion. Soe alternatives exist for the storage services, while the data confidentiality solutions for the database as a service paradig are still iature. It describes the architecture that integrates cloud database services with data confidentiality and the possibility of executing the concurrent operations on encrypted data. 1.7 Application of Distributed Database 7

5 Ferretti et al.[2014] [8] revealed that the success of the cloud database paradig is strictly related to strong guarantees in ters of service availability, scalability and security, but also of data confidentiality. Any cloud provider assures the security and availability of its platfor, while the ipleentation of scalable solutions to guarantee confidentiality of the inforation stored in cloud databases is an open proble left to the tenant. Existing solutions address soe preliinary issues through SQL operations on encrypted data. We propose the first coplete architecture that cobines data encryption, key anageent, authentication and authorization solutions, and that addresses the issues related to typical threat scenarios for cloud database services. Gill et al.[2014] [2] In these days, the security is essential for all the applications on the network. For providing the security to any applications on network, nubers of echaniss are used. But there is no ipleentation of any echanis for security on the N-tier architecture. The NTRU algorith is concluded as a best and fast algorith for providing security on the clouds. Hababeh [2010] [5] says that custoizing network sites have becoe an increasingly iportant issue in distributed database systes. This will iprove the network syste perforance by reducing the nuber of counications required for query processing in ters of retrieval and update transactions. This paper presents an intelligent clustering ethod for distributed database syste that provides a structure for organizing large nuber of network sites into a set of useful clusters to iniize transactions processing counications. It has been designed to divide the database network sites into a set of disjoint clusters based on a high perforance clustering technique. This can reduce the aount of redundant data to be accessed and transferred aong different sites, definitely increase the transaction perforance, database syste response tie, and result in better distributed network decision support. Mekala et al.[2014] [11] Cloud coputing is one of the ost increasing one with the increase nuber of cloud users. In today s environent every user wants to access their data at any tie and at anywhere. In an organization they store the data only on their coputers, if they want their data during the roaing situation eans it is not possible one to carry the data at every tie, this is a difficult factors for an organization. The Cloud coputing can address this proble by providing data storage echanis to access the data at anywhere. This is the storage device used to access their data at any where through networks which is called cloud provider. Yashpal Mote et al.[2012] [13] in their paper says about data encryption algorith, this algorith play iportant role in encrypting and decrypting the data there are present various types of the algorith that are AES, DES, Triple DES, NTRU, and each of these algorith have their specific role in day to day life. The two ain characteristics that identify and differentiate one encryption algorith fro another its ability to secure the protected data against attacks by hacker and its speed and efficiency. This paper provides a perforance coparison between five of the ost coon encryption algorith. This paper also presents a highly efficient ipleentation of NTRU. Fro the survey of the various existing systes it is concluded that whether there are so any ethods or algoriths which are used for the security purpose in the distributed database syste for file sharing but still they have soe probles, to overcoe these probles the NTRU is considered as the best algorith for the security purpose. Sr. Author Work done no nae 1 Gurkaa analyze the NTRU l Bhullar algorith, based Encryption decryption technique for security to Distributed Database 2 Luca Ferretti Syste. describes the architecture that integrates cloud database services with data confidentiality and the possibility of executing the concurrent operations on encrypted data. 8

6 3 L. Defines architecture that Ferretti cobines data encryption, key anageent, authentication and authorization solutions, and that addresses the issues related to typical threat scenarios for cloud database services. 4 Isail Oar presents an intelligent clustering ethod for Hababeh distributed database syste that provides a structure for organizing large nuber of network sites into a set of useful clusters to iniize transactions processing counications 5 Yashpal Mote provides a perforance coparison between five of the ost coon encryption algorith. This paper also presents a highly efficient ipleentation of NTRU. Table no. 1 Coparison of the existing systes by various authors. 3. Cryptographic Techniques Cryptography is the study of Secret (crypto-) and Writing (- graphy). It is the science or art of encopassing the principles and ethods of transforing an intelligible essage into one that is intelligible and then transforing the essage back to its original for. Today s cryptography is ore than encryption and decryption. Authentication is as fundaentally a part of our lives as privacy. We use authentication throughout our everyday lives when we sign our nae to soe docuent and for instance, as we ove to world where our decisions and agreeents are counicated electronically, we need to have electronic techniques for providing authentication. There are three types of cryptographic techniques: i. Syetric-key cryptography. ii. Asyetric-key cryptography. iii. Hash function cryptography. i Syetric-key cryptography- refers to encryption ethods in which both the sender and receiver share the sae key. Because of the sae key the encryption-decryption process is fast but ore security risks are here. Syetric-key encryption can use either strea ciphers or block ciphers. Strea ciphers encrypt the digits (typically bytes) of a essage one at a tie. Block ciphers take a nuber of bits and encrypt the as a single unit, padding the plaintext so that it is a ultiple of the block size. Blocks of 64 bits have been coonly used. The Data Encryption Standard (DES) and the Advanced Encryption Standard (AES) are block cipher designs which have been designated cryptography standards by the US governent (though DES's designation was finally withdrawn after the AES was adopted). Despite its deprecation as an official standard, DES (especially its still-approved and uch ore secure triple-des variant) reains quite popular; it is used across a wide range of applications, fro ATM encryption to e-ail privacy and secure reote access. Many other block ciphers have been designed and released, with considerable variation in quality and soe have been thoroughly broken. ii. Asyetric-key cryptography:- Public-key cryptography, also known as asyetric cryptography, is a class of cryptographic protocols based on algoriths that require two separate keys, one of which is secret (or private) and one of which is public. It is coputationally easy for a user to generate a public and private key-pair and to use it for encryption and decryption. Although different, the two parts of this key pair are atheatically linked. The public-key cryptography is ore secure because different keys are used for encryption and decryption. The various asyetric key algoriths are RSA, Diffie Hellan key exchange and Digital Signature Algorith. iii. Hash Functions-Hash functions, also called essage digests and one-way encryption algoriths that, in soe sense, use no key.instead, a fixed-length hash value is coputed based upon the plaintext that akes it ipossible for either the contents or length of the plaintext to be recovered. Hash algoriths are typically used to provide a digital fingerprint of a file's contents often used to ensure that the file has not been altered by an intruder or virus. Hash functions are also coonly eployed by any 9

7 operating systes to encrypt passwords. Hash functions, then, provide a easure of the integrity of a file. Mostly MD5 and SHA hash function cryptography are used for security purpose. Table no.2 shows the coparison of soe cryptographic techniques. Soe coonly used encryption algoriths are: DES: (Data Encryption Standard), was the first encryption standard to be recoended by NIST (National Institute of Standards and Technology). It is based on the IBM proposed algorith called Lucifer. DES becae a standard in Since that tie, any attacks and ethods recorded that exploit weaknesses of DES, which ade it an insecure block cipher. 3DES: As an enhanceent of DES, the3des (Triple DES) encryption standard was proposed. In this standard the encryption ethod is siilar to the one in original DES but applied 3 ties to increase the encryption level. But it is a known fact that 3DES is slower than other block cipher ethods. AES: (Advanced Encryption Standard), is the new encryption standard recoended by NIST to replace DES. It was originally called Rijndael (pronounced Rain Doll). It has variable key length of 128, 192, or 256 bits; default 256. AES encryption is fast and flexible; it can be ipleented on various platfors especially in sall devices. Table no. 2 coparison of cryptographic techniques NTRU: The NTRU Encryption schees is an interesting alternative to well established schees such as,rsa,des, ElGaal, and ECIES. The security of NTRU depends on the hardness of coputing short lattice vectors and thus is a proising user for being quantu coputer resistant. There has been extensive research on efficient ipleentation of the NTRU encryption schee. 4. ENCRYPTION ANALYSIS OF DES, RSA, NTRU In distributed database we work upon the concurrency and security, and our ain objective behind this work is to provide ore security to our data with the help of the NTRU algorith [12], because it is the latest algorith being introduced in the year 2009 and is approved by the institute of electrical engineers. This work is ainly done by the three atheaticians Jeffrey Hoff stein, Joseph H Silveran, Jill Pipher in the year 1996 and later at the end of 1996 these atheaticians plus Daneil founded the NTRU Paraeters Sye tric key Asy etric key Hash functio ns Speed up Fastest Slow Fast Collision resistant No No Yes Coplexity Less More cople x Key agreeent/ exchange A big proble No proble at all but this techniq ue requires a lot of athe atical calculat ions Less than asy etric No such proble at all Delays Less More Less than asy etric Security Software ipleentat ions Easily breakab le Difficul t Require s tables and cople x progra s Better than syet ric key Difficul t Require s tables and cople x progra s Iposs ible to break Siple donot require s tables and cople x progra s cryptosyste, and on 2009 it was approved. In the later part of this we are analyzing that perforance coparison between ostly used algoriths that are DES and RSA with NTRU. 10

8 Point s for discu ssion Ways of ensur ing securi ty Infor atio n leaka ge proba bility Exec ution tie Secur ity Break ing proba bility Identi ficatio n Based Model Only identif y the author ized person, so hacker can get access on databa se Sall File encry ption based Model Key & file both reain s in one server. So, getting access on one server helps to get all infor ation Secu red chan nel using ode l Intru der cant acces s the data, but uploa ded file is not secur ed Medi u Distri buted Serve r Based archit ecture Ensur es securit y in data excha nging proces s. Only gettin g contro l over full syste can leak infor atio n Low Sall Medi u Proba bly Low than others Fig: 1.4 Encryption Analysis The above graphical representation clearly identifies that as the no of bytes goes on increasing the tie to encrypt the data also increases in all the three cases but the NTRU needs less tie in encryption. Table no.3 Coparison of existing odels The table no.3 represents the coparison of the various existing odels which are used for the data security purpose in the distributed database syste environent and the cloud coputing environent. 5. CONCLUSION In our work we ainly deal with the distributed database, and in that we try to solve the concurrency and security. Concurrency eans when ore than one transaction were executed at the sae by the user, like if ore clicks on a particular site occur then traffic increases and this consequences will result the server crash, to avoid this proble proper easures were taken in order to avoid it. Security plays iportant role in this work as to protect our sensitive inforation fro the unauthorized user this will be conducted with the help of certain algorith and in that algorith we will try to adopt the asyetric approach. By NTRU being a strong encryption technique will surely provide the strong security as till date its has no security clauses which will prove to be a best fitted approach for our research thesis. 6. REFERENCES [1]. Gupta V.K., Sheetlani Jitendra, Gupta Dhirajand Shukla Braha, (2012), Data concurrency control and security issues of distributed database transaction NIMS University, Jaipur, Rajasthan, INDIA, 1(2), pp: [2]. Aandeep Kaur Gill, Charanjit Singh, (2014), Security of N-Tier Architecture using 11

9 NTRU, International Journal of Advanced Research in Coputer Science and Software Engineering, 4(7), pp: [3]. Dr. Lokanatha C. Reddy,( 2011), A Review on Data ining fro Past to the Future, International Journal of Coputer Applications,15(7). [4]. Gurkaal Bhullar, Navneet Kaur, (2014), Concurrency and Security Control with NTRU, International Journal of Innovative Research in Coputer and Counication Engineering, 2(3), pp: [5] Isail Oar Hababeh (2010), Intelligent Network Counications for Distributed Database Systes, Second International Conference on Advances in Databases, Knowledge, and Data Applications, pp: [6]. Luca Ferretti, Michele Colajanni, and Mirco Marchetti (2014), Distributed, Concurrent, and Independent Access to Encrypted Cloud Databases, Institute of Electrical and Electronics Engineers (IEEE), 25(2), pp: [7]. L. Ferretti, M. Colajanni, (2012), Supporting Security and Consistency for Cloud Database, Proc. Fourth Int l Syp. Cyberspace Safety and Security. [8] Luca Ferretti, Fabio Pierazzi, Michele Colajanni, and Mirco Marchetti, (2014), Scalable Architecture for Multi-User Encrypted SQL Operations on Cloud Database Services, Institute of Electrical and Electronics Engineers (IEEE), 2(4), pp: [9]. Ran Vijay Singh and M.P.S Bhatia, (2011), Data Clustering with Modified K-eans Algorith, IEEE International Conference on Recent Trends in Inforation Technology, pp [10]. Sheetlani Jitendra, Gupta V.K, (2012) Concurrency Issues of Distributed Advance Transaction Process, Res. J. Recent Sci., 1(2), pp: [11]. S.Mekala, M.Senthil Prabhu M.E, (2014), Survey on Encrypted Database in Cloud, International Journal of Advance Research in Coputer and Counication Engineering, 3(10), pp: [12]. Subedari Mithila, P. Pradeep Kuar, (2011), Data Security through Confidentiality in Cloud Coputing Environent, (IJCSIT) International Journal of Coputer Science and Inforation Technologies, Vol. 2, pp: [13].Yashpal ote and Shekhar Gaikwad, (2012), Superior security data encryption algorith International journal of engineering science, vol-6. 12