S1.2: n-Tier Concepts

• Presentation Tier

  • "Front Facing" systems WRT Client connectivity
  • Greatest Exposure and Visibility of WebServ System

• Application Tier

  • Multi-Tier depending on Application Program paradigm
  • May not be amenable to Clusters, Load Balancers, etc
  • “Glue Logic” design structure important for control
  • Heavy Interdependence on Presentation and Data

• Data Tier

  • Defined by the operational data characteristics
  • Optimization may depend on use

• Interconnectivity

  • Protocols, Protocols, Protocols
  • Security, Security, Security
  • Oh yeah – Management