Roles and Boundaries 角色与边界

本篇文章是对课程大型软件系统设计与体系结构(双语)【又名：云计算】第四章的课堂内容总结，适用于大连交通大学。

Fundamental Concepts and Models（基本概念和模型）

Roles and Boundaries 角色与边界

Cloud Provider 云提供者

• provides cloud-based IT resources
• as per agreed upon SLA guarantees
• ensure the on-going operation

Cloud Consumer 云用户

• an organization (or a human) that has a formal contract or arrangement to access a cloud service

Cloud Service Owner 云服务拥有者

• The person or organization that legally owns a cloud service

Cloud Resource Administrator 云资源管理者

• person or organization responsible for administering a cloud-based IT resource (including cloud services).

Additional Roles 其他角色

• Cloud Auditor 云审计者
• Cloud Broker 云代理
• Cloud Carrier 云运营商

Organizational Boundary 组织边界

• represents the physical perimeter that surrounds a set of IT resources that are owned and governed by an organization.

Trust Boundary 信任边界

• a logical perimeter that typically spans beyond physical boundaries to represent the extent to which IT resources are trusted

## Cloud Characteristics 云特征

• on-demand usage 按需使用
• ubiquitous access 随处访问
• multitenancy (and resource pooling) 多租户（和资源池）
• Elasticity 弹性
• measured usage 可测量的使用
• resiliency 可恢复性

On-Demand Usage 按需使用

• A cloud consumer can unilaterally access cloud-based IT resources giving the cloud consumer the freedom to self-provision these IT resources.
• on-demand self-service usage, this characteristic enables the service-based and usage-driven features found in mainstream clouds

Ubiquitous Access 无处不在地访问

• represents the ability for a cloud service to be widely accessible.

Multitenancy (and Resource Pooling) 多租户

• The characteristic of a software program that enables an instance of the program to serve different consumers (tenants) whereby each is isolated from the other
• Through the use of multitenancy technology, IT resources can be dynamically assigned and reassigned, according to cloud service consumer demands.

Elasticity弹性

• the automated ability of a cloud to transparently scale IT resources, as required in response to runtime conditions or as pre-determined by the cloud consumer or cloud provider

Measured Usage可测量的使用

• represents the ability of a cloud platform to keep track of the usage of its IT resources, primarily by cloud consumers.

Resiliency 可恢复性

• a form of failover that distributes redundant implementations of IT resources across physical locations.

Cloud Delivery Models 云交付模型

represents a specific, pre-packaged combination of IT resources offered by a cloud provider.

• Infrastructure-as-a-Service (IaaS) 基础设施作为服务
• Platform-as-a-Service (PaaS) 平台作为服务
• Software-as-a-Service (SaaS) 软件作为服务

infrastructure-as-a-Service (IaaS)

• The IaaS delivery model represents a self-contained IT environment comprised of infrastructure-centric IT resources that can be accessed and managed via cloud service-based interfaces and tools.
• This environment can include hardware, network, connectivity, operating systems, and other “raw” IT resources.
• infrastructure-as-a-Service (IaaS)

Platform-as-a-Service (PaaS)

• The PaaS delivery model represents a pre-defined “ready-to-use” environment typically comprised of already deployed and configured IT resources.

The cloud consumer wants to extend on-premise environments into the cloud for scalability and economic purposes. The cloud consumer uses the ready-made environment to entirely substitute an on-premise environment. The cloud consumer wants to become a cloud provider and deploys its own cloud services to be made available to other external cloud consumers.

Software-as-a-Service (SaaS)

• A software program positioned as a shared cloud service and made available as a “product” or generic utility represents the typical profile of a SaaS offering.

A comparison of typical cloud delivery model control levels

Typical activities carried out by cloud consumers and cloud providers in relation to the cloud delivery models

用火锅类比云计算交付模型

第一层IaaS

第二层PaaS

Cloud Deployment Models 云部署模型

• A cloud deployment model represents a specific type of cloud environment, primarily distinguished by ownership, size, and access.

Public cloud 公有云 Community cloud 社区云 Private cloud 私有云 Hybrid cloud 混合云

Public Clouds 公有云

• a publicly accessible cloud environment owned by a third-party cloud provider.
• The cloud provider is responsible for the creation and on-going maintenance of the public cloud and its IT resources.

Public Clouds

Community Clouds 社区云

• A community cloud is similar to a public cloud except that its access is limited to a specific community of cloud consumers.
• Membership in the community does not necessarily guarantee access to or control of all the cloud’s IT resources. Parties outside the community are generally not granted access unless allowed by the community.

Community Clouds

Private Clouds 私有云

• A private cloud is owned by a single organization.
• With a private cloud, the same organization is technically both the cloud consumer and cloud provider 1.a separate organizational department typically assumes the responsibility for provisioning the cloud (and therefore assumes the cloud provider role) 2.departments requiring access to the private cloud assume the cloud consumer role

Private Clouds

Hybrid Clouds 混合云

• A hybrid cloud is a cloud environment comprised of two or more different cloud deployment models.

summary

1.Fundamental Concepts

• Cloud Provider云提供者
• Cloud Consumer云用户
• Cloud Service Owner云服务拥有者
• Cloud Resource Administrator云资源管理者
• Organizational Boundary组织边界
• Trust Boundary信任边界

2.Cloud Characteristics

• on-demand usage按需使用
• ubiquitous access泛在连接
• multitenancy (and resource pooling)多租户和资源池
• Elasticity弹性
• measured usage可测量的使用
• Resiliency可恢复性

3.Cloud Delivery Models

• Infrastructure-as-a-Service (IaaS)基础设施作为服务
• Platform-as-a-Service (PaaS) 平台作为服务
• Software-as-a-Service (SaaS) 软件作为服务

4.Cloud Deployment Models

• Public cloud公有云
• Community cloud社区云
• Private cloud私有云
• Hybrid cloud混合云

个人博客本文地址：https://kohler19.gitee.io/2022/03/17/cloud-computing2/