Computer Network
Overview
- Formal definition: interconnected collection of computing devices.
- End systems(host):
e.g.pc’s, workstation,servers.
e.g.PDA’s, phone, toasters
run network application program :WWW.,e-mail - Computer network: provide communication services to allow data transfer between systems.
Computer Network uses
- Resource sharing
- Highly reliability
- Cost saving
- New way of communication
- Access to remote information(WWW,FTP…
- Exchange of information(Email,Wechat…
- Interactive entertainment(Video-on-demand,network gaming , Mp3,…
The Internet
- Global scale, general purpose, heterogeneous-technologies, public, Com.Net.
- Internet Protocol
1.Open standard
2.Technical basis for other types of networks - Developed by the research community
History
…
- Everyone is selfish and aggressive, wanna the max ratio of transmission -> conjunction
- Common language -> interconnecting network
Cerf and Kahn’s internetworking principles:
- minimalism, autonomy-no internet changes required to interconnect networks
- best effort service model
- stateless route
- decentralized control
define today’s Internet architecture