Characterizing and providing interoperability to function as a service platforms

Dissertação para obtenção do Grau de Mestre em Engenharia Informática e de ComputadoresA computação sem servidor abstrai o controlo da infraestrutura dos programadores e executa código a pedido com escalonamento automático onde apenas se é cobrado pela quantidade de recursos consumidos. Um dos serviços mais populares da computação sem servidor é a Função como Serviço (Function-as-a-Service ou FaaS), onde os programadores são muitas vezes confrontados com requisitos específicos dos prestadores de serviços de nuvem. Requisitos de assinatura das funções, e o uso de bibliotecas exclusivas ao prestador de serviços, foram identificados como sendo as principais causas de problemas de portabilidade das aplicações FaaS. O controlo reduzido da infraestrutura e a elevada dependência para com o prestador de serviços dá origem a diversos problemas de aprisionamento tecnológico. Neste trabalho, introduzimos o QuickFaaS, uma ferramenta para desktop de interoperabilidade multi-cloud com foco principal no desenvolvimento de funções agnósticas à nuvem e na criação das mesmas na respetiva plataforma. O QuickFaaS permite melhorar substancialmente a produtividade, flexibilidade e agilidade no desenvolvimento de soluções sem servidor para múltiplos prestadores de serviços, sem o requisito de instalar software adicional. A abordagem agnóstica à nuvem irá permitir que os programadores reutilizem as suas funções em diferentes prestadores de serviços sem terem a necessidade de reescrever código. A solução visa a minimizar o aprisionamento tecnológico nas plataformas FaaS através do aumento da portabilidade das funções sem servidor, incentivando assim programadores e organizações a apostarem em diferentes prestadores de serviços em troca de um benefício funcional.Serverless computing hides infrastructure management from developers and runs code on-demand automatically scaled and billed during code’s execution time. One of the most popular serverless backend services is called Function-as-a-Service (FaaS), in which developers are many times confronted with cloud-specific requirements. Function signature requirements, and the usage of custom libraries that are unique to cloud providers, were identified as the two main reasons for portability issues in FaaS applications. Such reduced control over the infrastructure and tight-coupling with cloud services amplifies various vendor lock-in problems. In this work, we introduce QuickFaaS, a multi-cloud interoperability desktop tool targeting cloud-agnostic functions development and FaaS deployments. QuickFaaS substantially improves developers’ productivity, flexibility and agility when creating serverless solutions to multiple cloud providers, without requiring the installation of extra software. The proposed cloud-agnostic approach enables developers to reuse their serverless functions in different cloud providers with no need to rewrite code. The solution aims to minimize vendor lock-in in FaaS platforms by increasing the portability of serverless functions, which will, therefore, encourage developers and organizations to target different providers in exchange for a functional benefit.N/

QuickFaaS: providing portability and interoperability between FaaS Platforms

Serverless computing hides infrastructure management from developers and runs code on-demand automatically scaled and billed during the code's execution time. One of the most popular serverless backend services is called Function-as-a-Service (FaaS), in which developers are often confronted with cloud-specific requirements. Function signature requirements, and the usage of custom libraries that are unique to cloud providers, were identified as the two main reasons for portability issues in FaaS applications, leading to various vendor lock-in problems. In this work, we define three cloud-agnostic models that compose FaaS platforms. Based on these models, we developed QuickFaaS, a multi-cloud interoperability desktop tool targeting cloud-agnostic functions and FaaS deployments. The proposed cloud-agnostic approach enables developers to reuse their serverless functions in different cloud providers with no need to change code or install extra software. We also provide an evaluation that validates the proposed solution by measuring the impact of a cloud-agnostic approach on the function's performance, when compared to a cloud-non-agnostic one. The study shows that a cloud-agnostic approach does not significantly impact the function's performance.info:eu-repo/semantics/publishedVersio

Enabling End-To-End Orchestration of Multi-Cloud Applications

The orchestration of application components across heterogeneous cloud providers is a problem that has been tackled using various approaches, some of which led to the creation of cloud orchestration and management standards, such as TOSCA and CAMP. Standardization is a definitive method of providing an end-To-end solution capable of defining, deploying, and managing applications and their components across heterogeneous cloud providers. TOSCA and CAMP, however, perform different functions with regard to cloud applications. TOSCA is focused primarily on topology modeling and orchestration, whereas CAMP is focused on deployment and management of applications. This paper presents a novel solution that not only involves the combination of the emerging standards TOSCA and CAMP, but also introduces extensions to CAMP to allow for multi-cloud application orchestration through the use of declarative policies. Extensions to the CAMP platform are also made, which brings the standards closer together to enable a seamless integration. Our proposal provides an end-To-end cloud orchestration solution that supports a cloud application modeling and deployment process, allowing a cloud application to span and be deployed over multiple clouds. The feasibility and the benefit of our approach are demonstrated in our validation study

MACHS: Mitigating the Achilles Heel of the Cloud through High Availability and Performance-aware Solutions

Cloud computing is continuously growing as a business model for hosting information and communication technology applications. However, many concerns arise regarding the quality of service (QoS) offered by the cloud. One major challenge is the high availability (HA) of cloud-based applications. The key to achieving availability requirements is to develop an approach that is immune to cloud failures while minimizing the service level agreement (SLA) violations. To this end, this thesis addresses the HA of cloud-based applications from different perspectives. First, the thesis proposes a component’s HA-ware scheduler (CHASE) to manage the deployments of carrier-grade cloud applications while maximizing their HA and satisfying the QoS requirements. Second, a Stochastic Petri Net (SPN) model is proposed to capture the stochastic characteristics of cloud services and quantify the expected availability offered by an application deployment. The SPN model is then associated with an extensible policy-driven cloud scoring system that integrates other cloud challenges (i.e. green and cost concerns) with HA objectives. The proposed HA-aware solutions are extended to include a live virtual machine migration model that provides a trade-off between the migration time and the downtime while maintaining HA objective. Furthermore, the thesis proposes a generic input template for cloud simulators, GITS, to facilitate the creation of cloud scenarios while ensuring reusability, simplicity, and portability. Finally, an availability-aware CloudSim extension, ACE, is proposed. ACE extends CloudSim simulator with failure injection, computational paths, repair, failover, load balancing, and other availability-based modules

A constraints-based resource discovery model for multi-provider cloud environments

Abstract Abstract Increasingly infrastructure providers are supplying the cloud marketplace with storage and on-demand compute resources to host cloud applications. From an application user’s point of view, it is desirable to identify the most appropriate set of available resources on which to execute an application. Resource choice can be complex and may involve comparing available hardware specifications, operating systems, value-added services (such as network configuration or data replication) and operating costs (such as hosting cost and data throughput). Providers’ cost models often change and new commodity cost models (such as spot pricing) can offer significant savings. In this paper, a software abstraction layer is used to discover the most appropriate infrastructure resources for a given application, by applying a two-phase constraints-based approach to a multi-provider cloud environment. In the first phase, a set of possible infrastructure resources is identified for the application. In the second phase, a suitable heuristic is used to select the most appropriate resources from the initial set. For some applications a cost-based heuristic may be most appropriate; for others a performance-based heuristic may be of greater relevance. A financial services application and a high performance computing application are used to illustrate the execution of the proposed resource discovery mechanism. The experimental results show that the proposed model can dynamically select appropriate resouces for an application’s requirements. </jats:sec

Flexible Deployment of Social Media Analysis Tools, Flexible, Policy-Oriented and Multi-Cloud deployment of Social Media Analysis Tools in the COLA Project

The relationship between companies and customers and among public authorities and citizens has changed dramatically with the widespread utilisation of the Internet and Social Networks. To help governments to keep abreast of these changes, Inycom has developed Eccobuzz and Magician, a set of web applications for Social Media data mining. The unpredictable load of these applications requires flexible user-defined policies and automated scalability during deployment and execution time. Even more importantly, privacy norms require that data is restricted to certain physical locations. This paper explains how such applications are described with Application Description Templates (ADTs). ADTs define complex topology descriptions and various deployment, scalability and security policies, and how these templates are used by a submitter that translates this generic information into executable format for submission to the reference framework of the COLA European projec

Platform as a service gateway for the Fog of Things

Internet of Things (IoT), one of the key research topics in recent years, together with concepts from Fog Computing, brings rapid advancements in Smart City, Monitoring Systems, industrial control, transportation and other fields. These applications require a reconfigurable sensor architecture that can span multiple scenarios, devices and use cases that allow storage, networking and computational resources to be efficiently used on the edge of the network. There are a number of platforms and gateway architectures that have been proposed to manage these components and enable application deployment. These approaches lack horizontal integration between multiple providers as well as higher order functionalities like load balancing and clustering. This is partly due to the strongly coupled nature of the deployed applications, a lack of abstraction of device communication layers as well as a lock-in for communication protocols. This is a major obstacle for the development of a protocol agnostic application environment that allows for single application to be migrated and to work with multiple peripheral devices with varying protocols from different local gateways. This research looks at existing platforms and their shortcomings as well as proposes a messaging based modular gateway platform that enables clustering of gateways and the abstraction of peripheral communication protocols. This allows applications to send and receive messages regardless of their location and destination device protocol, creating a more uniform development environment. Furthermore, it results in a more streamlined application development and testing while providing more efficient use of the gateways resources. Our evaluation of a prototype for the system shows the need for the migration of resources and the QoS advantages of such a system. The presented use-case scenarios show that clustering can prove to be an advantage in certain use-cases as well as the deployment of a larger testing and control environment through the platform

Network Infrastructures for Highly Distributed Cloud-Computing

Software-Defined-Network (SDN) is emerging as a solid opportunity for the Network Service Providers (NSP) to reduce costs while at the same time providing better and/or new services. The possibility to flexibly manage and configure highly-available and scalable network services through data model abstractions and easy-to-consume APIs is attractive and the adoption of such technologies is gaining momentum. At the same time, NSPs are planning to innovate their infrastructures through a process of network softwarisation and programmability. The SDN paradigm aims at improving the design, configuration, maintenance and service provisioning agility of the network through a centralised software control. This can be easily achievable in local area networks, typical of data-centers, where the benefits of having programmable access to the entire network is not restricted by latency between the network devices and the SDN controller which is reasonably located in the same LAN of the data path nodes. In Wide Area Networks (WAN), instead, a centralised control plane limits the speed of responsiveness in reaction to time-constrained network events due to unavoidable latencies caused by physical distances. Moreover, an end-to-end control shall involve the participation of multiple, domain-specific, controllers: access devices, data-center fabrics and backbone networks have very different characteristics and their control-plane could hardly coexist in a single centralised entity, unless of very complex solutions which inevitably lead to software bugs, inconsistent states and performance issues. In recent years, the idea to exploit SDN for WAN infrastructures to connect multiple sites together has spread in both the scientific community and the industry. The former has produced interesting results in terms of framework proposals, complexity and performance analysis for network resource allocation schemes and open-source proof of concept prototypes targeting SDN architectures spanning multiple technological and administrative domains. On the other hand, much of the work still remains confined to the academy mainly because based on pure Openflow prototype implementation, networks emulated on a single general-purpose machine or on simulations proving algorithms effectiveness. The industry has made SDN a reality via closed-source systems, running on single administrative domain networks with little if no diversification of access and backbone devices. In this dissertation we present our contributions to the design and the implementation of SDN architectures for the control plane of WAN infrastructures. In particular, we studied and prototyped two SDN platforms to build a programmable, intent-based, control-plane suitable for the today highly distributed cloud infrastructures. Our main contributions are: (i) an holistic and architectural description of a distributed SDN control-plane for end-end QoS provisioning; we compare the legacy IntServ RSVP protocol with a novel approach for prioritising application-sensitive flows via centralised vantage points. It is based on a peer-to-peer architecture and could so be suitable for the inter-authoritative domains scenario. (ii) An open-source platform based on a two-layer hierarchy of network controllers designed to provision end-to-end connectivity in real networks composed by heterogeneous devices and links within a single authoritative domain. This platform has been integrated in CORD, an open-source project whose goal is to bring data-center economics and cloud agility to the NSP central office infrastructures, combining NFV (Network Function Virtualization), SDN and the elasticity of commodity clouds. Our platform enables the provisioning of connectivity services between multiple CORD sites, up to the customer premises. Thus our system and software contributions in SDN has been combined with a NFV infrastructure for network service automation and orchestration

A look at cloud architecture interoperability through standards

Enabling cloud infrastructures to evolve into a transparent platform while preserving integrity raises interoperability issues. How components are connected needs to be addressed. Interoperability requires standard data models and communication encoding technologies compatible with the existing Internet infrastructure. To reduce vendor lock-in situations, cloud computing must implement universal strategies regarding standards, interoperability and portability. Open standards are of critical importance and need to be embedded into interoperability solutions. Interoperability is determined at the data level as well as the service level. Corresponding modelling standards and integration solutions shall be analysed