Well there are 2 red5’s, the open source red5 which is the one we use on our servers and red5pro, which is very expensive but still does not do what Wowza Streaming Engine does.
Red5 the open source can be used for ondemand streaming which is video streaming, you upload videos (in flv or mp4 format) to a red5 server and you stream the videos using red5, it is a better experience then using just a normal server, it starts faster because you don’t have to download the all file to the viewer computer and it is difficult for users to steal the video. But and this always applies, you can stream only to flash players, and most platforms are leaving flash, specially mobiles, so what I am saying is that red5 does not work well with smartphones, be Apple or Android devices.
You can also use red5 to stream live events, or video chats software’s.
Some of our customers ask what kind of servers we use. Although we have some older ones E5420, and the E5520, the latest ones we use are E5620 on a Lenovo RD240 box. 16 core, 48 giga of RAM connected on a 2 Gbps dedicated port.
This post was written in 2011. Nowadays (2018) we mostly use Dell servers with the following CPU, E5-2620 v3 , and 94 giga of RAM.