Migration to PaaS Clouds - Migration Process and Architectural Concerns

In the cloud computing technology stack, infrastructure has matured more than platform or software service technologies with respect to languages and techniques used for architecting and managing respective applications. Platform-asa- Service (PaaS) emerges as a focus for the near future that we will focus on. We look at software architecture and programming concerns in the context of migration to PaaS solutions, i.e. the transition of platform systems from on-premise to cloud solutions. We investigate best-practice approaches in cloud-aware coding in the form of patterns and formulate these as a migration process. While one-to-one mappings of software from on-premise to cloud platforms are possible, statelessness and data externalisation from stateful sessions and applications emerge as solutions if cloud benefits such as elasticity and performance are aimed at

Cloud migration patterns: a multi-cloud service architecture perspective

Many organizations migrate their on-premise software systems to the cloud. However, current coarse-grained cloud migration solutions have made a transparent migration of on-premise applications to the cloud a difficult, sometimes trial-and-error based endeavor. This paper suggests a catalogue of fine-grained service-based cloud architecture migration patterns that target multi-cloud settings and are specified with architectural notations. The proposed migration patterns are based on empirical evi-dence from a number of migration projects, best practices for cloud architectures and a systematic literature review of existing research. The pattern catalogue allows an or-ganization to (1) select appropriate architecture migration patterns based on their ob-jectives, (2) compose them to define a migration plan, and (3) extend them based on the identification of new patterns in new contexts

Pattern-based multi-cloud architecture migration

Many organizations migrate on-premise software applications to the cloud. However, current coarse-grained cloud migration solutions have made such migrations a non transparent task, an endeavor based on trial-anderror. This paper presents Variability-based, Pattern-driven Architecture Migration .V-PAM), a migration method based on (i) a catalogue of fine-grained service-based cloud architecture migration patterns that target multi-cloud, (ii) a situational migration process framework to guide pattern selection and composition, and (iii) a variability model to structure system migration into a coherent framework. The proposed migration patterns are based on empirical evidence from several migration projects, best practice for cloud architectures and a systematic literature review of existing research. Variability-based, Pattern-driven Architecture Migration allows an organization to (i) select appropriate migration patterns, (ii) compose them to define a migration plan, and (iii) extend them based on the identification of new patterns in new contexts. The patterns are at the core of our solution, embedded into a process model, with their selection governed by a variability model

Technical Report on Deploying a highly secured OpenStack Cloud Infrastructure using BradStack as a Case Study

Cloud computing has emerged as a popular paradigm and an attractive model for providing a reliable distributed computing model.it is increasing attracting huge attention both in academic research and industrial initiatives. Cloud deployments are paramount for institution and organizations of all scales. The availability of a flexible, free open source cloud platform designed with no propriety software and the ability of its integration with legacy systems and third-party applications are fundamental. Open stack is a free and opensource software released under the terms of Apache license with a fragmented and distributed architecture making it highly flexible. This project was initiated and aimed at designing a secured cloud infrastructure called BradStack, which is built on OpenStack in the Computing Laboratory at the University of Bradford. In this report, we present and discuss the steps required in deploying a secured BradStack Multi-node cloud infrastructure and conducting Penetration testing on OpenStack Services to validate the effectiveness of the security controls on the BradStack platform. This report serves as a practical guideline, focusing on security and practical infrastructure related issues. It also serves as a reference for institutions looking at the possibilities of implementing a secured cloud solution.Comment: 38 pages, 19 figures

A template description framework for services as a utility for cloud brokerage

Integration and mediation are two core functions that a cloud service broker needs to perform. The description of services involved plays a central role in this endeavour to enable services to be considered as commoditised utilities. We propose a conceptual framework for a cloud service broker based on two parts: a reference architecture for cloud brokers and a service description template that describes the mediated and integrated cloud services. Structural aspects of that template will be identified, formalised in an ontology and mapped onto a set of sublanguages that can be aligned to the cloud development and deployment process

A comparison framework and review of service brokerage solutions for cloud architectures

Cloud service brokerage has been identified as a key concern for future cloud technology development and research. We compare service brokerage solutions. A range of specific concerns like architecture, programming and quality will be looked at. We apply a 2-pronged classification and comparison framework.We will identify challenges and wider research objectives based on an identification of cloud broker architecture concerns and technical requirements for service brokerage solutions. We will discuss complex cloud architecture concerns such as commoditisation and federation of integrated, vertical cloud stacks

Scalable architectures for platform-as-a-service clouds: performance and cost analysis

Scalability is a significant feature of cloud computing, which ad-dresses to increase or decrease the capacities of allocated virtual resources at application, platform, database and infrastructure level on demand. We investigate scalable architecture solutions for cloud PaaS that allow services to utilize the resources dynamically and effectively without directly affecting users. We have implemented scalable architectures with different session state management solutions, deploying an online shopping cart application in a PaaS solution, and measuring the performance and cost under three server-side session state providers: Caching, SQL database and NoSQL database. A commercial solution with its supporting state management components has been used. Particularly when re-architecting software for the cloud, the trade-off between performance, scalability and cost implications needs to be discussed

Right Scaling for Right Pricing: A Case Study on Total Cost of Ownership Measurement for Cloud Migration

Cloud computing promises traditional enterprises and independent software vendors a myriad of advantages over on-premise installations including cost, operational and organizational efficiencies. The decision to migrate software configured for on-premise delivery to the cloud requires careful technical consideration and planning. In this chapter, we discuss the impact of right-scaling on the cost modelling for migration decision making and price setting of software for commercial resale. An integrated process is presented for measuring total cost of ownership, taking in to account IaaS/PaaS resource consumption based on forecast SaaS usage levels. The process is illustrated with a real world case study

Migration of an On-Premise Single-Tenant Enterprise Application to the Azure Cloud: The Multi-Tenancy Case Study

Kokkuvõte Pilvearvutuse edu muudab radikaalselt tavasid kuidas edaspidi infotehnoloogia teenuseid arendatakse, juurutatakse ja hallatakse. Sellest tulenevalt on sõnakõlks „pilve migratsioon“ vägagi aktuaalne paljudes ettevõtetes. Tänu sellele tehnoloogiale on paljud suured ja väikesed ettevõtted huvitatud enda tarkvara, andmebaasi süsteemide ja infrastruktuuri üleviimisest pilve keskkonda. Olemasolevate süsteemide migreerimine pilve võib vähendada kulutusi, mis on seotud vajamineva riistvara, tarkvara paigaldamise ning litsentseerimisega ja samuti selle kõige haldamiseks vajaminevate inimeste palkamisega. Rakenduse ja selle andmete hoidmine pilves, mis teenindab mitmeid üürnike (ik. tenants) võib osutuda kalliks kui ei kasutada jagatud lähenemist üürnike vahel. Sellest tulenevalt on teadlikult disainitud rakenduse ning andme arhitektuur äärmiselt oluline organisatsioonile, mis kasutab mitme-üürniku (ik. multi-tenant) lähenemist. Käesolevas magistritöös kirjeldatakse juhtumiuuringut (ik. case study) ning saadud kogemusi eraldiseiseva majasiseselt paigaldatava rakenduse migreerimisel Azure pilve keskkonda. Töö kirjeldab juristidele mõeldud tootlikkuse mõõtmise tarkvara andmekihi migreerimist Azure pilvekeskkonda. Majasisese ühe tarbijaga tarkvara andmekihi üleviimine efektiivsele mitme-üürniku andmekandja süsteemi pilve keskkonnas nõuab lisaks ka kõrgetasemelise autentimis-mehhanismi disainimist ning realiseerimist. Töö põhirõhk on turvalise skaleeruva ning mitme-üürniku efektiivse andmekandja süsteemi arhitektuuri disainimine ning realiseerimine pilve-keskkonda. Projektis kasutatakse SQL Database’i (endine SQL Azure) poolt pakutavat sisse ehitatud võimekust (SQL Federations) selleks, et tagada turvaline andmete eraldatus erinevate üürnike vahel ja andmebaasi skaleeruvus. Tarkvara andmekihi migreerimine pilve keskkonda toob kaasa kulude vähenemis, mis on seotud tarkvara tarnimisega, paigaldamise ning haldamisega. Lisaks aitab see ettevõttel laieneda uutele turgudele, mis enne migreerimist oli takistatud kohapeal teostava tarkvara paigaldamisega. Tänu pilves olevale andmekihile nõuab uuele kliendile süsteemi paigaldamine väga väikest kulutust.The success of cloud computing is changing the way how information technology services are developed, deployed, maintained and scaled. This makes the ‘migration to the cloud’ a buzzword in the industry for most of the enterprises today. Observing so many advantages of this phenomenon technology, enterprises from small to large scales are interested in migrating their software applications, database systems or infrastructures to cloud scale solutions. Migrating existing systems to a cloud scale solution can reduce the expenses related to costs of the necessary hardware for servers, installation of the operating system environment, license costs of the operating system and database products, deployment of the database products and hiring professional staff for keeping the system up and running. However, storing the application data to a back-end that serves multiple tenants on the cloud will be also costly if the resources on the cloud platform are not shared fairly among tenants. Thus, a carefully designed multi-tenant architecture is essential for an organization that serves multiple tenants. In this master thesis, we will describe a case study and lessons learned on the migration of an enterprise application from an on-premise deployment backend to the Azure Cloud. More specifically, the thesis describes the migration of a productivity tool specialized for legal professionals to a multi-tenant data storage back-ends on Azure Cloud. Moving an on-premise, single-tenant software backend to a multi-tenant data storage system on the cloud will also require design and implementation of authentication mechanisms. The core focus of the work consists of the design and implementation of a secure, scalable and multi-tenant efficient data storage system and application architecture on the cloud. SQL Database (formerly SQL Azure) offers native features (SQL Federations) for the secure isolation of the data among tenants and database scalability which has been used inside the project. Furthermore, the basic application authentication mechanism is enhanced with identity providers such as Google Account and Windows Live ID by embedding native functionality of Windows Azure called Azure Access Control Service to the login mechanism. Migration of the software backend to a cloud scale solution is expected to reduce the costs related to delivery, deployment, maintenance and operation of the software for the business. Furthermore, it will help the business to target new markets since it is a cloud based solution and requires very little initial effort to deliver the software to the new customers