Cloud and Datacenter Architecture Flashcards
Scalability
- Costs involved in supplying more of the service linearly
- If costs more than double for twice the users, it is less scalable
- Horizontal/scaling out: adding more nodes
- Vertical/scaling up: adding resources to each node
Elasticity
- Systems ability to handle changes in demand in real time
- Also able to reduce costs when demand is low
Resouce pooling
- Resources are not dedicated to single customer
Virtualization
- Provisioning resources using management software rather than hardware
Public Cloud Model
- Service offered to cloud consumers or tenants
- Subscriptions or pay as you go financing
- Often provide low tier services free of charge
- Risks from shared resources involve performance and security
Hosted Private
- Hosted by a third party exclusive use for one org
- More secure and better performance but more expensive
Private
- Owned by org
- One business unit often manages cloud services
- Greater control
- Often banking of government
Community
- Several orgs share costs of hosted private or fully private cloud
Hybrid
- A combination of the other cloud models
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IaaS
Infrastructure as a Service
- Provisioning servers, load balancers, SANs, etc. quickly.
- Renting as needed from service providers data center
SaaS
Software as a Service
- Access sofrware on vendors servers with Pay as you go or lease agreement.
- Virtual infrastructure allows provisioning on demand quickly
- Tested and developed in cloud without needing to be deployed on user computers
- 365, Salesforce, Gsuite
PaaS
Platform as a Service
- Somewhere between SaaS and Iaas
- Deploys servers and storage but provides webapplication/database platform on top
- Oracle or MS SQL or MySQL
- Platform would not be configured to do anything
- Your own developers would need to create software that runs using platforms like CRM or e-commerce
- Provider is responsible for integrity of platform components
DaaS
Desktop as a Service
- Removes need for org to deploy and maintain client PCs and software installs
API
Application Programming Interface
- Simplest way to access cloud services
- Can also be implemented with VPN
- Can suffer from performance issues from latency and bandwidth throttling
- Should not be a solution for mission critical or high volume applications
Internet/VPN Connection
- Connecting to cloud services over website or API
- VPN can be used if supported by cloud provider
- Cost effective and easy to implement for distributed users
- Can suffer from poor performance and latency from the public internet
Colocation/Private direct
- A direct link to the data center
- Or customer infrastructure in Cloud provider data center
- Better for orgs with more centralized operations where connection to cloud can be from main HQ
IaC
Infrastructure as Code
- Infrastructure management where automation and orchestration to replace manual configuration
Snowflake System
- System with unique build or configuration
- Inconsistency creates security issues and problems as scripts fail because of configuration differences
Automation
- configuration and building done by code
- Imperative: require precise steps to follow to achieve configuration. Similar to scripting languages
- Declarative: Take desired configuration as input and leave details to implementation platform
Orchestration
- Performing a series of automated tasks
- Steps must take place in the correct sequence taking dependencies into account
Cloud Responsibility Matrix
- Identifying responsibilities you and the provider are taking in SLA
