Cloud Computing Chapter3
Understanding Cloud Computing(理解云计算)
--A Brief History
1961,computer scientist John McCarthy publicly proposed
1969 ARPANET project “spread of computer utilities”
Mid-1990s google, email,facebook,
Late 1990s salesforce.com remotely provisioned service
2002 Amazon web services platform
2006 - the term
cloud computing(云计算 )emerged in the commercial arena.
Amazon launched its Elastic Compute Cloud（弹性云计算） (EC2) services that enabled organizations to “lease” (租赁)computing capacity and processing power to run their enterprise applications.
Google Apps also began providing
browser-basedenterprise applications in the same year, and three years later, the
Google App Enginebecame another historic milestone.
a style of computing in which
scalable and elasticIT-enabled capabilities are delivered
as a serviceto external customers using Internet technologies.
a standardized IT capability (services, software, or infrastructure) delivered via Internet technologies in a
Cloud computing is a model for enabling
ubiquitous, convenient, on-demandnetwork 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 book (4):
Cloud computing is a specialized form of
distributed computingthat introduces
scalable and measuredresources.
Business Drivers 商业驱动力
--Capacity Planning 容量规划：
• the process of determining and fulfilling future demands of an organization's IT resources, products, and services.
• capacity planning strategies:
1.Lead Strategy – adding capacity to an IT resource in anticipation of demand
2.Lag Strategy – adding capacity when the IT resource reaches its full capacity
3.Match Strategy – adding IT resource capacity in small increments, as demand increases
--Cost Reduction 降低成本
--Organizational Agility 组织灵活性
Technology Innovations 技术创新
a group of independent IT resources that are interconnected and work as a single system. System failure rates are reduced while availability and reliability are increased, since redundancy and failover features are inherent to the cluster.
--Grid Computing 网格计算
provides a platform in which computing resources are organized into one or more logical pools.
a technology platform used for the creation of virtual instances of IT resources.
-Technology Innovations vs. Enabling Technologies 计算创新和使能技术
--A cloud refers to a distinct IT environment that is designed for the purpose of remotely provisioning scalable and measured IT resources.
--An IT resource is a physical or virtual IT-related artifact that can be either software-based, such as a virtual server or a custom software program, or hardware-based, such as a physical server or a network device .
An IT resource that is on-premise cannot be cloud-based ---An on-premise IT resource can access and interact with a cloud-based IT resource.
--An on-premise IT resource can be moved to a cloud, thereby changing it to a cloud-based IT resource.
--Redundant deployments of an IT resource can exist in both on-premise and cloud-based environments
Cloud Consumers and Cloud Providers
--cloud provider 云提供者
The party that provides cloud-based IT resources
--cloud consumer 云用户
The party that uses cloud-based IT resources
--Horizontal Scaling 水平扩展
--Vertical Scaling 垂直扩展
－scaling out 向外扩展
－scaling in 向内扩展
－scaling up 向上扩展
－scaling down 向下扩展
Cloud Service 云服务
A cloud service is any IT resource that is made remotely accessible via a cloud.
motivation behind cloud computing is to provide IT resources as services that
encapsulate other IT resources
a service-level agreement (SLA)
Cloud Service Consumer 云服务用户
temporary runtime role assumed by a software program when it
accesses a cloud service
Reduced Investments and Proportional Costs(降低的投资与成比例的开销)
--Common measurable benefits to cloud consumers include:
On-demand access to pay-as-you-go computing resources
The perception of having unlimited computing resources
The ability to add or remove IT resources at a fine-grained level
Abstraction of the infrastructure
Increased Scalability (提高的可扩展性)
--Cloud consumers can scale or release their cloud-based IT resources automatically or manually.
--To provide flexible levels of scalability to IT resources is the inherent, built-in feature of clouds
Increased Availability and Reliability(提高的可用性和可靠性)
--An IT resource with increased availability is accessible for longer periods of time (for example, 22 hours out of a 24 hour day). Cloud providers generally offer “resilient” IT resources for which they are able to guarantee high levels of availability.
--An IT resource with increased reliability is able to better avoid and recover from exception conditions. The modular architecture of cloud environments provides extensive failover support that increases reliability
--Increased Security Vulnerabilities 增加的安全漏洞
--Reduced Operational Governance Control 降低的运营管理控制
--Limited Portability Between Cloud Providers 云提供者之间有限的可移植性
--cloud computing 云计算
--IT resource IT资源
--cloud consumer 云用户
--cloud provider 云提供者
-- horizontal scaling 水平扩展
--vertical scaling 垂直扩展
--cloud service 云服务
-- cloud service consumer 云服务用户