# What's Cloud Computing? --- ## Could Computing Cloud computing is the delivery of computing services over the Internet (“the cloud”) to offer faster innovation, flexible resources, and economies of scale. --- ### Attributes - High Availability (高可用) - Scalability (延展性) - Elasticity (彈性) - Agility (敏捷性) - Geo-Distribution (地理分佈) - Disaster Recovery (災難還原) - Security (安全) - Predictive cost consideration (可預測費用) --- ## Financial Consideration --- ### Capital Expenditure - 資產出現在資產負債表 - Increase 商業價值 - 透過折舊來節稅 - 高提前費用–時間越久越沒價值 --- ### Operational Expenditure - 費用出現在損益表 - 減少淨利 - 收入變少所以稅變少 - 沒有提前費用–用多少花多少 --- ## Type of Cloud --- ### 3 types of cloud - Public - Private - Hybrid --- ### Public - Service provided by provider - Provide multiple organization & users - Access by Public Network --- ### Private - Service provided by organization's on-site data center or by third-party service provider. - Internal use only - 公司或者組織外部不能夠連線 --- ### Hybrid - 把內部(private) 和外部(public) 打通 - Public cloud 變成Private Cloud 的延伸 - 也有可能是兩個雲之間的打通 --- ## Type of Service --- ### Share Responsibility What if you cannot access your service on Cloud, and who should take the response --- ### IaaS vs PaaS vs SaaS  ref: [https://www.redhat.com/en/topics/cloud-computing/iaas-vs-paas-vs-saas](https://www.redhat.com/en/topics/cloud-computing/iaas-vs-paas-vs-saas) --- ### IaaS  --- ### PaaS  --- ### SaaS  --- ### E.g. Azure SQL Server  --- ### Serverless - Don't need to care about VM - According to usage to scale - e.g. Azure Function, Azure Logic App --- ### Thank you!