The best replacement for wowza is red5.

The best alternatives to wowza are rated as following:
★★★★★  red5
★★★  cloudfront
★★★  helix
★★★  flash media server
★★  kaltura
★★  icecast
★  fms
★  erlyvideo
★  ffserver
  adobe media server

Your alternative for wowza is not listed? Suggest!
Speaking about wowza, one probably shouldn't forget about jw player.

Other search terms related to wowza and their ratings are:
★★★★★ jw player
★★★ cloudfront
★★ wirecast
★★ flowplayer
You have in mind a companion for wowza and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of wowza in all years. Click on graph for more.
wowza
red5
cloudfront