lesson1 multmedia

Streaming, storedaudio, video

DASH

• streaming: can begin playout before downloading entire file

• stored (at server): can transmit faster than audio/video will be rendered (implies storing/buffering at client)

• e.g., YouTube, Netflix, Hulu

Conversational voice/video over IP

VoIP

• interactive nature of human-to-human conversation limits delay tolerance e.g., Skype

Streaming live audio, video

e.g., live sporting event (futbol)

Real-time Transport Protocols: RTP/RTCP/RTSP/SIP

RTP: 运行在UDP 之上，就是封装在UDP包中。

RTP不提供服务质量保证。RTCP来control

QoS

区分不同的流量类型提供不同等级的服务。

此外，要防止饿死

速率的调节是一种重要的QoS机制。

lesson2 Internet Applications

DNS

HTTP

CDN

cache