Encompass computation, storage, and networking and security

Replacement Cost

• Exponential increase in cost to maintain the infrastructure
• Vendor Lock-in

No standard API or protocol can be very serious

• Standardization

No standard metric for QoS is limiting the popularity

• Security and Confidentiality

No standard metric for QoS is limiting the popularity

Trust model for cloud computing

• Control Mechanism
• Users do not have any control over infrastructures

Concerns from Research Community

• Conflict to legacy programs
  • With difficulty in developing a new application due to lack of control
• Provenance
  • How to reproduce results in different infrastructures
• Reduction in Latency
• No specially designed interconnect used
  • Very low controllability in layout of interconnect due to abstraction
• Programming Model
  • Hard to debug where programming naturally error-prone
  • Details about infrastructure are hidden
• QoS Measurement
  • Especially for ubiquitous computing where context changes

Comparing compute clusters

• Instance performance
  • Java-based benchmarks
• Cost-effectiveness
  • Cost per benchmark
• Scaling performance
  • Why is it important?
  • Scaling latency

Comparing storage services

• Cover blob, table, and queue storage services
• Compare “read” and “write” operations
  • Additional “query” operation for table
• Metrics
  • Operation latency
  • Cost per operation
  • Time to consistency
• Network latency to the closest data center

Storage performance

• Operation response time has high variation
• Storage performance depends on operation type

Three metrics

• • Benchmark finishing time
  • Monetary cost per benchmark
  • Scaling latency

End-to-end metrics

• Simple
• Has predictive value
• Abstracts away the implementation details
  • Different design trade-offs
  • No single one stands out
  • Cloud performance can vary significantly
    • 30% more expensive -> twice as fast
    • Storage performance can differ in magnitudes
    • One cloud’s intra-data center bandwidth can be 3X higher than the other

Security and Confidentiality (abstraction of the underlying infrastructure)

• Multi-tenancy (shared environments, may or may not have access to software)
  • Economical because software development and maintenance costs are shared. It can be contrasted with single-tenancy, an architecture in which each customer has their own software instance and may be given access to code
• Single-tenancy (an architecture in which each customer has their own software)
  • The provider has to touch multiple instances of the software in order to make updates.
• Security and Confidentiality
• IT Audit Risk is largely driven by:
  • • Deployment Model
    • Service Model

   

• Nature of Applications & Data in Cloud