Notes for BSc CSIT

 Elastic IP address An Elastic IP address is a static IPv4 address designed for dynamic cloud computing. An Elastic IP address is associated with your AWS account. With an Elastic IP address, you can mask the failure of an instance or software by rapidly remapping the address to another instance in your account.  An Elastic IP address is a public IPv4 address, which is reachable from the Internet. If your instance does not have a public IPv4 address, you can associate an Elastic IP address with your instance to enable communication with the Internet; for example, to connect to your instance from your local computer.  Elastic IP addresses are used by AWS to manage its dynamic cloud computing services. Within the AWS infrastructure, customers have virtual private clouds (VPCs). Within the VPCs, users have instances. The Elastic IP address is what is used to advertise the data within the instance to the public internet. Works: Each EIP can be assigned to one instance, in which case it rep

 Infrastructure as a Service (IaaS) is one of the three fundamental service models of cloud computing alongside Platform as a Service (PaaS) and Software as a Service (SaaS). Infrastructure as a Service is a provision model in which an organization outsources the equipment used to support operations, including storage, hardware, servers, and networking components.  The service provider owns the equipment and is responsible for housing, running, and maintaining it. The client typically pays on a per-use basis. Clients are able to self-provision this infrastructure, using a Web-based graphical user interface that serves as an IT operations management console for the overall environment. API access to the infrastructure may also be offered as an option. IaaS is usually seen to provide a standardized virtual server. The consumer takes responsibility for the configuration and operations of the guest Operating System (OS), software, and Database (DB). Compute capabilities (such as performanc

  Service-oriented architecture (SOA)  Service-oriented architecture (SOA) references a set of principles and methodologies applied by software engineers to design and develop software in the form of interoperable services. Services are usually built in the form of components that can be reused for different purposes than originally intended. For this reason, the interfaces are often defined in a practical manner, allowing use across varying applications and multiple platforms. The principal characteristics of SOA are described in more detail here: SOA is black-box component architecture. The black box lets you reuse existing business applications; it simply adds a fairly simple adapter to them. You don’t need to know every detail of what’s inside each component; SOA hides the complexity whenever possible. SOA components are loosely coupled. Software components are loosely coupled if they’re designed to interact in a standardized way that minimizes dependencies. One loosely coupled com

Amazon Elastic Compute Cloud (Amazon EC2)  Amazon Elastic Compute Cloud (Amazon EC2) is an Amazon Web Service (AWS) you can use to access servers, software, and storage resources across the Internet in a self-service manner. It provides scalable, pay-as-you-go compute capacity. It is said to be elastic since it is scalable in both directions along the client as well as the service provider.  Amazon EC2 provides the following features: Virtual computing environments, known as instances Preconfigured templates for your instances, known as Amazon Machine Images (AMIs), that package the bits you need for your server (including the operating system and additional software) Various configurations of CPU, memory, storage, and networking capacity for your instances, known as instance types  Secure login information for your instances using key pairs (AWS stores the public key, and you store the private key in a secure place) Storage volumes for temporary data that are deleted when you stop or

  Platform as a Service PaaS, or Platform as a Service, is simply a cloud basis where you can create, test, and organize various apps for your organization. Implementing PaaS streamlines the company's software development process.  Paas's virtual runtime environment provides a conducive environment for creating and testing applications. The full set of resources available in the form of servers, storage, and networking can be managed by the organization or a platform provider.  PaaS services such as Google App Engine and AWS Elastic Beanstalk are  common examples.  PaaS is also subscription-based, giving you various pricing options based on your business's needs. PaaS provides - Applications Deployment - Configuring application components - Provisioning and configuring supporting technologies The Essential Characteristics of PaaS 1. Runtime Framework This is the “software stack” aspect of PaaS, and perhaps the aspect that comes first to mind for most people. The PaaS runtim

Virtualization  Virtualization is the "creation of a virtual (rather than actual) version of something, such as a server, a desktop, a storage device, an operating system or network resources". In other words, Virtualization is a technique, which allows sharing a single physical instance of a resource or an application among multiple customers and organizations. It does by assigning a logical name to physical storage and providing a pointer to that physical resource when demanded. The role of Virtualization in a Cloud Environment 1. Protection from System Failures Technology is always at risk of crashing down at the wrong time. Businesses can tolerate a few glitches, but if your developer is working on an important application that needs to be finished immediately, the last thing you could wish for is a system crash. To counter this risk, virtualization lets you open the same work on another device. Store all your backup data through virtualization on cloud services or virtua

 Platform as a service (PaaS) Platform as a service (PaaS) is a category of cloud computing services that provide a computing platform and a solution stack as a service. Along with software as a service (SaaS) and infrastructure as a service (IaaS), it is a service model of cloud computing. PaaS offerings facilitate the deployment of applications without the cost and complexity of buying and managing the underlying hardware and software and provisioning hosting capabilities. Technically, a PaaS is an Application Platform comprised of an operating system, middleware, and other software that allows applications to run on the cloud with much of the management, security, scaling, and other stack-related headaches abstracted away. This allows you to focus on two things: customers and developing your application. Let the PaaS deal with system administration details like setting up servers or VMs, installing libraries or frameworks, configuring testing tools, etc. Platform as a Service allows