ISSN: 2278 – 1323 International Journal of Advanced Research in Computer Engineering & Technology (IJARCET) Volume 2, Issue 3, March 2013 884 All Rights Reserved © 2013 IJARCET Cloud Computing: An Architecture, its Security Issues & Attacks Kalpana N. Meher, Prof. P. S. Lokhande Abstract — Every day new things are added in old and those things should have to be preserve for managing the future, new things are always come with the major question that where should keep the things safely? This concept is applicable for both the regular household things as well as the computer data. Day by day storage requirements are increasing but storage space is the same for preserving the data securely. For storing extra data the computer users may invest extra cost on separate storage devices or choose the newly added feature in IT environment is ‘Cloud Computing’. Cloud computing has extended feature of the distributed computing; it is a way to increase the capacity or add capabilities without investing in new infrastructure, training new personal or licensing new software. This paper mainly focused on the architecture of cloud computing; survey of the different security issues that has emanate due to the nature of the service delivery module of cloud computing system and type of attacks in cloud computing environment. Keywords — Cloud computing, cloud security, cloud providers, cloud standards, cloud attacks, software as a service (SaaS), platform as a service (PaaS), infrastructure as a service (IaaS) I. INTRODUCTION Cloud computing is extended feature of distributed computing, the evolutionary growth of many existing technologies and approaches most basic computing, separates applications and information resources from the underlying infrastructure and mechanisms used to deliver them with the addition of flexible scale and utility mode of allocation. Also the cloud computing enhances collaboration, agility, scale, ability and helps in the cost reduction though optimized and efficient computing. Because of unpredictable need of data; the storage requirements in personal computing as well as in industries is increased rapidly. Storage requirements can be manageable in small-scale industries or in personal computer; but still they have to manage the storage periodically. Some times needs extra investment on storage. Cloud describes the use of a collection of service, applications; information and infrastructure comprise of pools of computer, network, information, storage resources. These components can be rapidly arranged, provisioned, implemented and decommissioned also scale up or scale down as per the demand. By using cloud components, the small and medium business companies are realizing that by investing very small amount in to the cloud they can gain fast access to business applications or can increase their infrastructural resources. For providing a cloud services cloud computing involves a provider delivering a verity of it enable resources to consumer as a service over internet. At the front end there are client computers and the application require to access the cloud computing system and at the back end there are various computers, servers and data storage systems that creates the ‗cloud‘ services. As these services provided by the cloud user need not have any knowledge or expertise in system that support them, or Indeed any control over those systems. II. ARCHITECTURE A. The NIST (National Institute of Standards and Technology) Definition of Cloud Computing Cloud computing is a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction. This cloud model is composed of five essential characteristics, three service models, and four deployment models.[1]