Cloud computing

Editor's Notes

• #11: In the 70’s , IT was based on dedicated servers and networks were made of leased lines. The result was high costs and no flexibility. In the 80’s , IT and network became shared, thanks to client-server models, IPVPN’s, and of course the revolution of the Internet. This led to increased flexibility and reduced costs BUT no rapid scalability, a lot of IT resource was still wasted, and definitely not close to the business. Then , enabled by new virtualization technologies, Cloud Computing arrived with on-demand services, bearing many promises, starting with flexibility, a faster adaptation to business requirements and usage-based billing. But Cloud Computing as it is today does not fully meet enterprises' needs: it creates complexity: for each cloud service you need, you have to deal with a different service provider, each with a specific order process, a specific bill, a specific management portal, and specific support process. What’s more, your applications do not communicate! And the multiplication of providers and portals creates potential user management security issues it lacks the performance guarantees that enterprises need for their critical applications: the providers of cloud computing services based on internet access typically do not offer any SLAs or only offer SLAs for the elements that they control within their data center. In addition, access through the internet does not allow quality of service management or acceleration which can latency or congestion and a poor end-user experience. it doesn’t addresses enterprises' security concerns because the public Internet is not by nature designed to guarantee data security and confidentiality. As a result, Internet-class Clouds are only to be used for non-critical environments and do not allow massive adoption of offers as a service. = = = = = = additional comments re. security some internet-based cloud computing service providers state that it is up to the customer to add security in their virtual environment only few of them propose IPSec tunnels over the Internet e.g. Amazon with their Virtual private-cloud offer. encryption and strong end-to-end authentication may help to mitigate the security risks of the internet to an adequate level. But it’s still not sufficient for entreprises who have strict security and confidentiality requirements.
• #14: We now know that we can handle big scale virtualisation and get the benefits. 1.5 MW is a small – medium sized town. Resource provisioning wasn’t a major target, but we have made huge improvements, which not only serve the business better but have an additional effect on costs. Most of the servers we’ve virtualised are production. We’re now one of the biggest adopters of V m ware around.
• #16: On-demand self-service. A consumer can unilaterally provision computing capabilities, such as server time and network storage, as needed automatically without requiring human interaction with each service’s provider. Broad network access. Capabilities are available over the network and accessed through standard mechanisms that promote use by heterogeneous thin or thick client platforms (e.g., mobile phones, laptops, and PDAs). resource pooling. The provider’s computing resources are pooled to serve all consumers using a multi-tenant model, with different physical and virtual resources dynamically assigned and reassigned according to consumer demand. The customer generally has no control or knowledge over the exact location of the provided resources but may be able to specify location at a higher level of abstraction (e.g., country, state, or datacenter). Examples of resources include storage, processing, memory, network bandwidth, and virtual machines. Rapid elasticity. Capabilities can be rapidly and elastically provisioned to quickly scale up and rapidly released to quickly scale down. To the consumer, the capabilities available for provisioning often appear to be infinite and can be purchased in any quantity at any time. Measured Service. Cloud systems automatically control and optimize resource use by leveraging a metering capability at some level of abstraction appropriate to the type of service (e.g., storage, processing, bandwidth, and active user accounts). Resource usage can be monitored, controlled, and reported providing transparency for both the provider and consumer of the utilized service. Scalable pricing , pricing needs to be rapidly scalable, up or down, to match the real usage of resources. Cloud Software as a Service (SaaS). The capability provided to the consumer is to use the provider’s applications running on a cloud infrastructure and accessible from various client devices through a thin client interface such as a Web browser (e.g., web-based email). The consumer does not manage or control the underlying cloud infrastructure, network, servers, operating systems, storage, or even individual application capabilities, with the possible exception of limited user-specific application configuration settings. Cloud Platform as a Service (PaaS). The capability provided to the consumer is to deploy onto the cloud infrastructure consumer-created applications using programming languages and tools supported by the provider (e.g., java, python, .Net). The consumer does not manage or control the underlying cloud infrastructure, network, servers, operating systems, or storage, but the consumer has control over the deployed applications and possibly application hosting environment configurations. Cloud Infrastructure as a Service (IaaS). The capability provided to the consumer is to rent processing, storage, networks, and other fundamental computing resources where the consumer is able to deploy and run arbitrary software, which can include operating systems and applications. The consumer does not manage or control the underlying cloud infrastructure but has control over operating systems, storage, deployed applications, and possibly select networking components (e.g., firewalls, load balancers). Private cloud. The cloud infrastructure is owned or leased by a single organization and is operated solely for that organization. Note that the provider gives a company the illusion that it is benefiting from a private environment but this does not necessarily mean that resources are not shared. In fact, we believe that there MUST be some level of resource-sharing (which can fluctuate depending on the needs of the customer and their budget) to be truly cloud and deliver elasticity and cost-savings. Public cloud. The cloud infrastructure is owned by an organization selling cloud services to the general public or to a large industry group. Hybrid cloud . The cloud infrastructure is a composition of two clouds (private and public) that remain unique entities but are bound together by standardized or proprietary technology that enables data and application portability (e.g., cloud bursting).