Internet
What’s the Internet?
Nuts and Bolts View
實質性內容
- End systems
- Running network apps
- e.g. PC, smart phone
- Communication Links
- wireless, wired
- e.g. fiber, copper, radio, satellite
- transmission rate: bandwidth
- Core for the network
- router and switch
- Protocol
- Internet standards
- RFC: Request for comments
- IETF: Internet Engineering Task Force
Internet: “network of networks”
Service View
Infrastructure that provides services to applications
- web, email, etc. Provides programming interface to apps
- hooks that allow app program to connect to Internet
Internet Structure
Network Edge
The end systems, what actually use the Internet.
Access Network and Physical media
Wired, wireless communication links, what allow the edge to connect to the Internet.
- residential access nets
- institutional access networks (school, company)
- mobile access networks (wireless)
Network Core
Interconnected router, which construct the “network of networks”.