RTMP和HTTP的八項參數比較

		RTMP	HTTP
Port Number		1935	80
Video Delivery		RTMP server streams video bytes from any point of time according to client’s request. Good for long content video	HTTP is designed to progressive download video
Cache		Video is stored at flash player’s memory	Video is stored at web browser’s buffer before playback
Video Codec Suggestions		·         Better use Constant Bit-rate (CBR) encoding; ·         Variable Bit-rate (VBR) encoded video might contain data spikes which can abruptly empty the flash player’s temporal cache and result in annoying pause-play-pause experience;	Can safely use VBR encoding since video are progressively downloaded. Extreme data spikes might not impact during playback
Firewall		Firewalls might disable1935 port. RTMP takes two polices to deal with firewall: ·         If play video over port 1935 fails, RTMP over port 80 is used; ·         If port 80 still fails, RTMP packets are wrapped in HTTP packets;	In default, almost all the firewalls allow HTTP connections over port 80
Video Access Control		Most users can only watch video content. (Of course the hackers can steal any video stream.) RTMP is useful for companies distributing movies	Users can fish the flash content out of the web browser cache
Hosting		Limited servers support RTMP services, e.g. RED5[1], FMS[2], Wowza[3], etc	Any HTTP web server such as the widely used Apache[4]
Cos t	Data Transfer Cost	Cost accounts only the streamed video	Cost accounts since flash video starts to download to browser cache and continues to download even users are not watching
	Implementation Cost	expensive	cheap

[1]http://www.red5.org/

[2]http://www.adobe.com

[3]http://www.wowza.com

[4]http://www.apache.org/