Cloud Computing

1. Cloud computing is a model which allows computing resources to be shared and configured across a network
2. Consumers can pay for what they use on a pay-as-you go model
3. Cloud services are accessible anywhere and anytime
4. Actors
   1. Consumer
      1. Access resources from centralised off site facility
      2. Rent computer resources as needed
   2. Provider

      Nota:

      • e.g.: Amazon web services
      1. Offers computing resources to consumers on pay-per-usage model
      2. Can offer storage, networking capabilities, server usage, and applications
      3. Profit margins can be maintained by using low cost premises to store large scale data centers
   3. Broker
      1. Intermediary between provider and consumer
      2. Assists consumer to select resources needed
      3. Negotiates relationship between provider and consumer

1. Cloud computing architecture can be divided into three tiers
   1. Deployment models
      1. Public
         1. Infrastructure available to general public
         2. Services offered on a pay per usage basis
         3. Resources are scaled according to demand and without interaction
         4. Resources maintained by third party
         5. Lack of control over where resources are stored and with whom
         6. Benefits small organisations by saving on capital expenses
      2. Private
         1. Available for one organisation
         2. Run through enterprise data center
         3. Managed by organisation or third party
         4. In house data centers require significant capital expenses
         5. Upfront costs more expensive than public cloud
         6. greater control over resources and IT infrastructure
         7. Fewer data security concerns due to better control over storage and access of data
         8. Larger organisations have shown a preference for private cloud
      3. Community
         1. Supports two or more organisations with a similar interest
         2. Popular among small to medium businesses
         3. Can be managed internally or by third parties
         4. Organisations agree on T&Cs to share resources
         5. Must agree on security, privacy and compliance
         6. Capital expenses shared among communtiy
         7. Can implement higher data security and privacy than public clouds
         8. Aspects of public and private
      4. Hybrid
         1. Most complex deployment model consisting of two or more cloud infrastructures
         2. Combination of public and private allows for some resources to be managed in house and others to be outsourced
         3. Outsource non-critical info and manage important info in house
         4. Cost benefits of public cloud + control of data in private cloud
         5. Need to consider security concerns of the public cloud component
         6. Once secure can be more flexible than private and public cloud
   2. Service models
      1. IaaS

         Nota:

         • Amazon web services provides IaaS successfully
         1. Service provider manages virtualisation, servers, storage and networking (see diagram)
         2. advantages
            1. Only pay for resources to deploy application
            2. Traditionally good support, performance and security
            3. Don't have to worry about complexities of hardware for deployment
      2. PaaS

         Nota:

         • example of PaaS is the Google application engine
         1. On top of IaaS the service provide manages the OS, Middleware and Runtime
         2. Consumers provided with resources for developing, managing and deploying applications
         3. advantages
            1. Can use PaaS to develop, test and deploy applications
         4. Billed for # of users and amount of resources consumed
         5. Limited access to underlying infrastructure
      3. SaaS

         Nota:

         • Salesforce.com is one of the most successful firms to use SaaS
         1. Consumer uses service providers computer infrastructure and software
         2. Multi-tenancy makes SaaS applications flexible and confiigurable
         3. SaaS provider manages and controls all resources (compared with PaaS and IaaS)
         4. Advantages
            1. No complexity associated with infrastructure provision, maintaining software
      4. Also HaaS, DaaS and BIaaS
   3. Essential characteristics
      1. On-demand self service
         1. Provision of services on demand and without interaction
         2. Real time response to change in demand
      2. Broad network access
         1. Access resources independent of location and through a variety of platforms
         2. Promotes productivity through flexibility
      3. Resource pooling
         1. Pool resources to create a shared environment
         2. Virtual and physical resources are pooled and redistributed to consumers
         3. Can serve multiple customers with different needs
      4. Rapid elasticity
         1. Dynamically re-purpose resources to meet demand
         2. Possible through virtualisation
         3. Helps utilise resources effectively
         4. Consumers can respond effectively to changes in demand
      5. Measured service
         1. Providers monitor, control and report on resources usage
         2. Resources can be controlled and optimised through measuring
         3. Measuring forms basis of pay-per-usage model

1. Cost Efficiency
   1. Reduced upfront capital expenses
      1. Transfer of risks and IT infrastructure to provider
   2. Pay-per-usage model
      1. Pay for what's used
2. Data recovery
   1. Backups automatically generated
3. Minimal staff
   1. Processes are automated
   2. Staff only needed when problems can't be solved by automated processes
   3. Cloud doesn't require staff for operations
4. Broad access
   1. Can access resources from multiple platfoms in a range of locations
5. Scalability
   1. Resources can be scaled elastically to meet demands
   2. Doesn't require long term planning or commitments
6. Management
   1. Providers responsible for maintenence, support and management
   2. Updates and bug fixes handled by providers
   3. Allows to focus on core business activities
7. Barriers to entry
   1. Reduced cost and risk reduces barriers to entry
   2. Small to medium businesses benefit the most
   3. Resources can be scaled to meet demand

1. Security
   1. Lack of control and visibility
   2. Security relating to data transmission, application and 3rd party
   3. Dependent on deployment
2. Privacy
   1. Concerns due to the many devices, applications and customers on the network
   2. Sharing of resources(multi tenancy)
   3. Lack of visibility of enforcement of controls
3. Lock-in
   1. Data lock in from change in ownership from consumer to provider
   2. Providers has ownership and control over data
4. Interoperability and integration
   1. Difficulty in transferring data between providers
   2. Difficulty in integrating APIs with legacy systems
5. Availability
   1. Absence of meaningful Service level agreements(SLA)
   2. SLAs provide customers with an outline of the availability of servers, platforms and appl
   3. If resources are not available it could have severe impacts on business
   4. Risk SLA is not reliable or comprehensive or is deceptive

1. Costs and benefits
   1. Other benefits
      1. Fewer upgrades and maintenace costs
      2. Reduced IT staff costs
   2. Costs
      1. Constant internet connection
2. Customer retention
   1. reduced costs
   2. On demand self service
3. Risk Management
   1. Reduce risks through choice of deployment and service model
   2. Investigate offerings from providers to ensure they have state of the art tech
   3. Inspect SLA
      1. Minimum levels for each service
      2. remedies for failing to meet contract
      3. Outline of infrastructure and security
      4. Rights of consumers
   4. People issues
      1. Employee issues(resistance and training)
      2. Provider issues(SLA, transparency and relationships)

Nota:

• Vendors Amazon Web services - IaaS Microsoft IBM Oracle - BI PaaS

1. IaaS has the largest market share

1. Hybrid cloud computing
2. Cloud centric design

   Nota:

   • Application designed for limitations and opportunities of a cloud model
3. Spending on private clouds