2022-05-22
  • Topic: Cloud Foundamentals
  • The path to cloud computing
    • Grid
      • EU: E-infrastructures
      • US: Cyber-infrastructure
      • UK: E-science
    • Edge
      • Shared computation with cloud
        • some processing remotely
        • some locally
      • Fog, same idea as Edge
  • Definition
    • Cloud computing: services on the internet
    • Cloud: a model for utility computing, for shearing resources
    • Cloud: a type of distributed system with virutualized computers
    • SLA: service level aggrement, core concept on service orient architecture, a legal document to be implemented by computer engineers
  • The cloud:
    • Most important advantage: user never manages machines
  • Reference model:
    • Cloud provider: people/org that provides computing resources (Infrastructure, Platform, Software)
    • In therory: IaaS, SaaS, PaaS can come frome different providers
  • Cloud research keywords
  • Gartner reports "IT Hype Cycle" of every technology
    • hype: a large amount of noise (bullshit)
    • Technology trigger: e.g. the invetion of iPhone
    • Peak of infalted expectation: 拿着锤子，看什么都是钉子
    • Through of disillusionment: at this stage most tech died, some survived
    • Slope of enlightenment, Plateau of productivity
    • Check gartner report every year, it tells you whether the technology is mature
  • Topic: Cloud Architecture
    • Service oriented computing (SOA): explicit boundary (contract), self-descriptive, service discovery
      • Web Services tech stack: service flow (WSFL) -> service discovery -> ... -> Network (HTTP, etc.)
      • Similar to IP network (host discovery, layered design, message protocol......)
    • Architecture:
      • "Bare metal": hardware
      • Virtualization layer
      • Cloud hosting platform (expose VM's as services)
      • PaaS: Cloud programming environment
    • IaaS reference implementation
      • Surge computing
        • Surge: a sudden peak
    • PaaS reference implementation