Introduction to Cloud Computing

👉    The Evolution of cloud computing. 

1.    Standalone Systems 

       - The systems which are installed in the local machine to acquire the service.
       - This is in contrast with grid-computing and work remotely.
       - This software applications are not connected to the network and has the ability to operate when offline.

2.    Client - Server.

       - The software application is installed in the server.
       - Clients access the server remotely.
       - In early stage thin clients were used but with time thick clients were introduced.

3.    Web-applications.

       - Access the applications through internet to acquire the service.

       - Web clients can be thin or either thick.

       - The applications are accessed through web browser which requires an active network connection.

4.    Super Computing.

       - This is a computing process which refers to processing of massively complex or data-laden problems using the concentrated computer resources of multiple computer systems working in parallel.

       - This type is mainly used in computation heavy tasks.

    

5.    Cluster Computing.

       - This is a process where many servers are grouped to obtain one fully functional server.

       - This helps to obtain high performance and availability.

       - The servers in the cluster are linked through a LAN network.

6.    Grid Computing.

       - Combining different cluster in different locations to obtain a grid structure.

       - This is used widely used in scientific processes.

       - High performance and availability is ensured by grid computing

👉    Cloud computing. 

*    Cloud computing is an internet process which is the illusion of infinite computer resources, elimination of up-front commitment by cloud users and pay for the use as needed. [Berkeley RADLabs]

*    Cloud computing is a utility service which gives access to tech resources by an expert/experts which is available on demand.

👉    Key ideas of Cloud computing.

*    Pay as you go on. - Pay for the amount used in the cloud services.

*    Self-service interface - The interface for cloud users for monitoring and metering of cloud connection.

*    Auto-scaling    -    Allocating the resource dynamically without under-provisioning or over-provisioning.

👉    Enabling technologies of Cloud computing.

*    Virtual machines.

*    Virtual Storage.

*    Load balancing.

*    Auto-scaling.

*    Monitoring & metering.

👉    Examples of Cloud computing.

*    Amazon EC2.

*    Microsoft Azure.

👉    Virtualization in Cloud computing.

*    Virtual Machine. - Run multiple machines in one machine.

*    Virtual Storage  -  logical space to store data.

*    Virtual Network    -    SDN (Software Defined Network).

👉    Auto-scaling in Cloud computing.

*    Allocating of resources according to the need of the cloud user to avoid under-provisioning and over-provisioning.

👉    Types of cloud - based on structure.

*    Public clouds    -    Open to general public, multi-tenant, no operational or capital cost.

*    Private clouds    -    Restricted only to the owner, solo-tenant, high operational and capital cost.

*    Hybrid clouds    -    This is kind of private cloud but in case need more resource move to public cloud to store or process some insensitive data.

*    Community clouds    -    This is restricted for a specific community like the university students.

👉    Types of cloud - based on service.

*    Iaas (Infra-structure as a service)    -    Create a cloud infrastructure like the virtual machine, disk space, memory , etc.

*    Paas (Platform as a service)    -    Installing a service or application in the cloud platform and obtaining the service. Eg. Tomcat Server

*    Saas (Software as a Service)    -    Using the software in cloud to obtain the service. 

Eg. Microsoft 365.