Notes for BSc CSIT

  CLOUD SERVICE REQUIREMENTS 1. Efficiency/cost reduction By using cloud infrastructure, you don’t have to spend huge amounts of money on purchasing and maintaining equipment. 2. Data security Cloud offers many advanced security features that guarantee that data is securely stored and handled. Cloud storage providers implement baseline protections for their platforms and the data they process, such as authentication, access control, and encryption. 3. Scalability Different companies have different IT needs — a large enterprise of 1000+ employees won’t have the same IT requirements as a start-up. Using the cloud is a great solution because it enables enterprises to efficiently — and quickly — scale up/down according to business demands. 4. Mobility Cloud computing allows mobile access to corporate data via smartphones and devices, which is a great way to ensure that no one is ever left out of the loop. Staff with busy schedules, or who live a long way away from the corporat...

 MapReduce  MapReduce is triggered by the map and reduces operations in functional languages, such as Lisp. This model abstracts computation problems through two functions: map and reduce. All problems formulated in this way can be parallelized automatically. All data processed by MapReduce are in the form of key/value pairs. The execution happens in two phases. In the first phase, a map function is invoked once for each input key/value pair and it can generate output key/value pairs as intermediate results. In the second one, all the intermediate results are merged and grouped by keys. The reduce function is called once for each key with associated values and produces output values as the final results. A map function takes a key/value pair as input and produces a list of key/value pairs as output. The type of output key and value can be different from input key and value: map::(key1,value1) => list(key2,value2) A reduce function takes a key and associated value list as in...

  CLOUD SERVICES Cloud computing service models are divided into three categories: Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS) (SaaS). There are evident distinctions between the three in terms of what they can provide a business in terms of storage and resource sharing, but they may also interact with one another to build a single comprehensive cloud computing platform. 1. IaaS (Infrastructure as Service):  This is the most prevalent cloud computing service architecture since it provides the underlying infrastructure of virtual servers, networks, operating systems, and data storage devices. It provides the flexibility, stability, and scalability that many organizations desire from the cloud while eliminating the need for hardware in the office. This makes it excellent for small and medium-sized businesses seeking a cost-effective IT solution to support business growth. IaaS is a completely outsourced pay-for-use service th...

  Cloud The “cloud” in cloud computing can be defined as the set of hardware, networks, storage, services, and interfaces that combine to deliver aspects of computing as a service. Cloud services include the delivery of software, infrastructure, and storage over the Internet. A cloud service is any service made available to users on demand via the Internet from a cloud computing provider's servers as opposed to being provided from a company's own premises servers explained before, the most common cloud service is that one offers data storage disks and virtual servers, i.e. infrastructure. Examples of Infrastructure-as-a-Service (IaaS) companies are Amazon, Rackspace, and Flexi scale. Cloud computing is the use of computing resources (hardware and software) that are delivered as a service over a network (typically the Internet).  Cloud computing is the on-demand availability of computer system resources, especially data storage (cloud storage) and computing power, without direc...

 Disaster recovery (DR)   Disaster recovery (DR) is an area of security planning that aims to protect an organization from the effects of significant negative events. DR allows an organization to maintain or quickly resume mission-critical functions following a disaster. A disaster can be anything that puts an organization's operations at risk, from a cyberattack to equipment failures to natural disasters. The goal with DR is for a business to continue operating as close to normal as possible. The disaster recovery process includes planning and testing and may involve a separate physical site for restoring operations. The recovery point objective (RPO) differs from the recovery time objective (RTO):- Recovery point objective (RPO) and recovery time objective (RTO) are two important measurements in disaster recovery and downtime. RPO is the maximum age of files that an organization must recover from backup storage for normal operations to resume after a disaster. The recov...

Data center virtualization  Data center virtualization is the process of designing, developing, and deploying a data center on virtualization and cloud computing technologies. It primarily enables virtualizing physical servers in a data center facility along with storage, networking, and other infrastructure devices and equipment. Data center virtualization usually produces a virtualized, cloud, and collocated virtual/cloud data center. Virtualization, Offering profound changes to the way data centers perform, virtualization makes sense on multiple levels.  The benefits of data center virtualization are as below: 1. Less heat buildup Millions of dollars have gone into the research and design of heat dissipation and control in the data center. But the cold, hard fact is, all of those servers generate heat. The only way around that? Use fewer servers. How do you manage that? Virtualization. Virtualize your servers and you're using less physical hardware. Use less physical hardwa...

Manages Service Providers (MSP)  A managed service provider (MSP) is a company that remotely manages a customer's IT infrastructure and/or end-user systems, typically on a proactive basis and under a subscription model. The MSP business model differs from other types of channel companies, such as value-added resellers (VARs), in numerous ways described below. MSPs charge for their services under a number of different pricing models. Typical approaches include per-device, per-user and all-inclusive pricing. 2nd part In the past, the concept of providing a service involved much more than inventing and designing the service, itself. The appropriate amount and quality of hardware were required for every company to not only build their service but have an adequate amount of space to hold and maintain the hardware for the life of each service, as well. Fortunately, that on-premise era is slowly but surely passing, leaving those rather dated companies still attempting to manage their own ...