Notes for BSc CSIT

 Virtualization is one of the key components of the cloud computing paradigm, especially in infrastructure as a service model where the mentioned technology is essential to provide a large set of computing resources. Some experts even define cloud computing as simple as virtualized hardware and software plus advanced monitoring and resource management technologies. To say it straight and clear, without virtualization, cloud computing would leave the data unstable, uncontrolled, and unsafe. It is an important and probably an inseparable element of cloud computing services. Virtualization allows us to consolidate multiple physical components so that they can be managed in one place. With the help of virtualization, organizations have better visibility and also greater control of their infrastructure making security management simpler for the cloud. It is due to virtualization that cloud computing services are so cost-effective. Moreover, it is also responsible for the simplicity of deliv

 A service-oriented architecture is essentially a collection of services. These services communicate with each other. The communication can involve either simple data passing or it could involve two or more services coordinating some activity. The reality in IT enterprises is that infrastructure is heterogeneous across operating systems, applications, system software, and application infrastructure. Some existing applications are used to run current business processes, so starting from scratch to build new infrastructure isn't an option. Enterprises should quickly respond to business changes with agility; leverage existing investments in applications and application infrastructure to address newer business requirements; support new channels of interactions with customers, partners, and suppliers; and feature an architecture that supports organic business. SOA with its loosely coupled nature allows enterprises to plug in new services or upgrade existing services in a granular fashio

 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