Skip to main content

SaaS characteristics

All Software as a Service (SaaS) applications share the following characteristics:

  1. The software is available over the Internet globally through a browser on demand. 
  2. The typical license is subscription-based or usage-based and is billed on a recurring basis. In a small number of cases a flat fee may be changed, often coupled with a maintenance fee. 
  3. The software and the service are monitored and maintained by the vendor, regardless of where all the different software components are running. There may be executable client-side code, but the user isn’t responsible for maintaining that code or its interaction with the service.
  4. Reduced distribution and maintenance costs and minimal end-user system costs generally make SaaS applications cheaper to use than their shrink-wrapped versions.
  5. Such applications feature automated upgrades, updates, and patch management and much faster rollout of changes.
  6. SaaS applications often have a much lower barrier to entry than their locally installed competitors, a known recurring cost, and they scale on demand (a property of cloud computing in general). 
  7. All users have the same version of the software so each user’s software is compatible with another’s.
  8. SaaS supports multiple users and provides a shared data model through a single-instance, multi-tenancy model.

The alternative of software virtualization of individual instances also exists, but is less common.




Comments

Popular posts from this blog

2.1 VIRTUAL MACHINES PROVISIONING AND MANAGEABILITY

In this section, we will have an overview on the typical life cycle of VM and its major possible states of operation, which make the management and automation of VMs in virtual and cloud environments easier than in traditional computing environments As shown in Figure above, the cycle starts by a request delivered to the IT department, stating the requirement for creating a new server for a particular service.  IT administration to start seeing the servers’ resource pool, matching these resources with the requirements, and starting the provision of the needed virtual machine.  Once provisioned machine started, it is ready to provide the required service according to an SLA, or a time period after which the virtual is being released.

1.2 ROOTS OF CLOUD COMPUTING

We can track the roots of clouds computing by observing the advancement of several technologies, especially in hardware (virtualization, multi-core chips), Internet technologies (Web services, service-oriented architectures, Web 2.0), distributed computing (clusters, grids), and systems management (autonomic computing, data center automation).  Below Figure shows the convergence of technology fields that significantly advanced and contributed to the advent of cloud computing. . We present a closer look at the technologies that form the base of cloud computing, with the aim of providing a clearer picture of the cloud ecosystem as a whole. 1.2.1 From Mainframes to Clouds 1.2.2 SOA, Web Services, Web 2.0, and Mashups 1.2.3 Grid Computing 1.2.4 Utility Computing 1.2.5 Hardware Virtualization 1.2.6 Virtual Appliances and the Open Virtualization Format 1.2.7 Autonomic Computing ______ Cloud computing has its roots in several technologies and developments, including virtualization, gr...

2.1.1 VM Provisioning Process

  Steps to Provision VM. Here, we describe the common and normal steps of provisioning a virtual server: Firstly, you need to select a server from a pool of available servers (physical servers with enough capacity) along with the appropriate OS template you need to provision the virtual machine. Secondly, you need to load the appropriate software (operating system you selected in the previous step, device drivers, middleware, and theneeded applications for the service required). Thirdly, you need to customize and configure the machine (e.g., IP address, Gateway) to configure an associated network and storage resources. Finally, the virtual server is ready to start with its newly loaded software. These are the tasks required or being performed by an IT or a data center’s specialist to provision a particular virtual machine.