P4L4 - Datacenter Technologies Flashcards
What is an internet service
Any type of service accessible via a web interface
How do users communicate with internet services?
Traditionally via web requests issued by their web browers
Describe how internet services are commonly divided
- Presentation Tier - static content related to webpage layout
- Business Logic Tier - Business-specific processing
- Database Tier - Data storage /management
T/F: The different tiers of internet services do not need to run as separate processes on separate machines
True!
What can be used to connect the components of an internet services
middleware
Describe the concept of homogeneous architecture
Any node can process any type of request and perform any of the processing actions that is required
What are the benefits of homogeneous architectures
Front-end load balance can be kept very simple
What is a downside of homogeneous architecture
Little opportunity to benefit from caching!
Describe the concept of heterogeneous architecture
Different nodes are designated to perform certain functions or handle certain types of requests
What is a benefit of heterogeneous architecture?
System can benefit from caching and locality
What is a downside of heterogeneous architecture?
Front-end needs to be more complex. It now needs to perform some request parsing to determine which node it should route the request to
What are the goals of cloud computing?
- On demand elastic resources and services
- Fine grained pricing based on usage
- Professionally managed and hosted
- API-based access
What does cloud computing provide?
Shared resources
Why does cloud computing work
- Law of large numbers - Average resource needs across a large number of clients will remain fairly constant
- Economies of Scale - Cloud provide is able to leverage a large number of customers on a single piece of hardware
List the cloud deployment models
- Public clouds
- Private clouds
- Hybrid cloud
- Community Clouds