Zusammenfassung der Ressource
Cloud Computing
- Overview
- Cloud computing is a model which allows computing resources to be shared and configured across a network
- Consumers can pay for what they use on a pay-as-you go model
- Cloud services are accessible anywhere and anytime
- Actors
- Consumer
- Access resources from centralised off site facility
- Rent computer resources as needed
- Provider
Anmerkungen:
- e.g.: Amazon web services
- Offers computing resources to consumers on pay-per-usage model
- Can offer storage, networking capabilities, server usage, and applications
- Profit margins can be maintained by using low cost premises to store large scale data centers
- Broker
- Intermediary between provider and consumer
- Assists consumer to select resources needed
- Negotiates relationship between provider and consumer
- Cloud Computing architecture
- Cloud computing architecture can be divided into three tiers
- Deployment models
- Public
- Infrastructure available to general public
- Services offered on a pay per usage basis
- Resources are scaled according to demand and without interaction
- Resources maintained by third party
- Lack of control over where resources are stored and with whom
- Benefits small organisations by saving on capital expenses
- Private
- Available for one organisation
- Run through enterprise data center
- Managed by organisation or third party
- In house data centers require significant capital expenses
- Upfront costs more expensive than public cloud
- greater control over resources and IT infrastructure
- Fewer data security concerns due to better control over storage and access of data
- Larger organisations have shown a preference for private cloud
- Community
- Supports two or more organisations with a similar interest
- Popular among small to medium businesses
- Can be managed internally or by third parties
- Organisations agree on T&Cs to share resources
- Must agree on security, privacy and compliance
- Capital expenses shared among communtiy
- Can implement higher data security and privacy than public clouds
- Aspects of public and private
- Hybrid
- Most complex deployment model consisting of two or more cloud infrastructures
- Combination of public and private allows for some resources to be managed in house and others to be outsourced
- Outsource non-critical info and manage important info in house
- Cost benefits of public cloud + control of data in private cloud
- Need to consider security concerns of the public cloud component
- Once secure can be more flexible than private and public cloud
- Service models
- IaaS
Anmerkungen:
- Amazon web services provides IaaS successfully
- Service provider manages virtualisation, servers, storage and networking (see diagram)
- advantages
- Only pay for resources to deploy application
- Traditionally good support, performance and security
- Don't have to worry about complexities of hardware for deployment
- PaaS
Anmerkungen:
- example of PaaS is the Google application engine
- On top of IaaS the service provide manages the OS, Middleware and Runtime
- Consumers provided with resources for developing, managing and deploying applications
- advantages
- Can use PaaS to develop, test and deploy applications
- Billed for # of users and amount of resources consumed
- Limited access to underlying infrastructure
- SaaS
Anmerkungen:
- Salesforce.com is one of the most successful firms to use SaaS
- Consumer uses service providers computer infrastructure and software
- Multi-tenancy makes SaaS applications flexible and confiigurable
- SaaS provider manages and controls all resources (compared with PaaS and IaaS)
- Advantages
- No complexity associated with infrastructure provision, maintaining software
- Also HaaS, DaaS and BIaaS
- Essential characteristics
- On-demand self service
- Provision of services on demand and without interaction
- Real time response to change in demand
- Broad network access
- Access resources independent of location and through a variety of platforms
- Promotes productivity through flexibility
- Resource pooling
- Pool resources to create a shared environment
- Virtual and physical resources are pooled and redistributed to consumers
- Can serve multiple customers with different needs
- Rapid elasticity
- Dynamically re-purpose resources to meet demand
- Possible through virtualisation
- Helps utilise resources effectively
- Consumers can respond effectively to changes in demand
- Measured service
- Providers monitor, control and report on resources usage
- Resources can be controlled and optimised through measuring
- Measuring forms basis of pay-per-usage model
- Benefits and Drivers
- Cost Efficiency
- Reduced upfront capital expenses
- Transfer of risks and IT infrastructure to provider
- Pay-per-usage model
- Pay for what's used
- Data recovery
- Backups automatically generated
- Minimal staff
- Processes are automated
- Staff only needed when problems can't be solved by automated processes
- Cloud doesn't require staff for operations
- Broad access
- Can access resources from multiple platfoms in a range of locations
- Scalability
- Resources can be scaled elastically to meet demands
- Doesn't require long term planning or commitments
- Management
- Providers responsible for maintenence, support and management
- Updates and bug fixes handled by providers
- Allows to focus on core business activities
- Barriers to entry
- Reduced cost and risk reduces barriers to entry
- Small to medium businesses benefit the most
- Resources can be scaled to meet demand
- Risk and concerns
- Security
- Lack of control and visibility
- Security relating to data transmission, application and 3rd party
- Dependent on deployment
- Privacy
- Concerns due to the many devices, applications and customers on the network
- Sharing of resources(multi tenancy)
- Lack of visibility of enforcement of controls
- Lock-in
- Data lock in from change in ownership from consumer to provider
- Providers has ownership and control over data
- Interoperability and integration
- Difficulty in transferring data between providers
- Difficulty in integrating APIs with legacy systems
- Availability
- Absence of meaningful Service level agreements(SLA)
- SLAs provide customers with an outline of the availability of servers, platforms and appl
- If resources are not available it could have severe impacts on business
- Risk SLA is not reliable or comprehensive or is deceptive
- Management Issues
- Costs and benefits
- Other benefits
- Fewer upgrades and maintenace costs
- Reduced IT staff costs
- Costs
- Constant internet connection
- Customer retention
- reduced costs
- On demand self service
- Risk Management
- Reduce risks through choice of deployment and service model
- Investigate offerings from providers to ensure they have state of the art tech
- Inspect SLA
- Minimum levels for each service
- remedies for failing to meet contract
- Outline of infrastructure and security
- Rights of consumers
- People issues
- Employee issues(resistance and training)
- Provider issues(SLA, transparency and relationships)
- Market Assessment
Anmerkungen:
- Vendors
Amazon Web services - IaaS
Microsoft
IBM
Oracle - BI PaaS
- IaaS has the largest market share
- Future trends
- Hybrid cloud computing
- Cloud centric design
Anmerkungen:
- Application designed for limitations and opportunities of a cloud model
- Spending on private clouds