Wowza Community

How to map UDP ports to Wowza server?


I’m trying to play RTSP stream from Wowza server. I can play the stream with x-vlc-plugin embedded in an html file, but the negotiation time before the stream plays is always quite long (~7-8 seconds) and the latency of the stream is large, probably 4-5 seconds (way behind the rtmp stream playing in JWPlayer which is about 1-2 seconds). I thought rtsp should be faster than rtmp, because it should be using UDP for transport whereas rtmp is stuck with TCP. But when I fire up wireshark it looks like rtsp is going all over TCP anyway.

On the guides here it says:

To stream to RTSP/RTP be sure UDP ports 0-65535 are open and properly mapped to the server running Wowza Media Server

Not sure about how to go about this. Does it mean open on the client local machine, on the ADSL router, or both?

  1. How can I open UDP ports 0-65535 and map them to wowza server?

  2. How can I verify whether or not a UDP port is open and mapped to wowza server?

I would also be interested to know if there are any other popular players that I can embed in html which will work well with wowza server rtsp stream, because I’m finding the vlc plugin a bit clunky (video corrupts and stuff, hard to configure).

Hi wim.glenn,

That sentence is a little ambiguous. Which guide is that? See the Wowza User Guide under the section “Ports Used For Streaming”.

You can probably ignore any notion of “mapping”.

If you’re going to stream to a flash player why not just use RTMP?

You can use network administration tools like netcat, to make a server that listens on UDP ports, and thus figure out if you have a firewall blocking that port. Otherwise you can look at your firewall rules.

It sounds like the UDP ports are blocked and VLC is trying to stream over UDP and failing then switching to TCP.


What do the Wowza Server logs look like when you try to play back the stream using RTSP? If you are trying play the stream using VLC be sure the:

Tools->Preferences->Input & Codecs->Live 555 stream transport

Is set to HTTP (default). Which is a bit of a misleading name but that will instruct VLC to try UDP first.


Hi randall and charlie, thanks for your replies…

The guide I was referring to is here:

And the sentence is in the section headed To play using RTSP/RTP player or device. I will check with a combination of nmap and nc to make sure ports UDP 6970-9999 aren’t blocked.

I am wanting to try RTSP as opposed to RTMP because as far as I’m aware RTMP must go over TCP, but RTSP can be configured to go over UDP and/or TCP. For performance reasons and aiming for lowest possible latency, then RTSP seems to be a better choice for video transport, correct me if I’m wrong. There is also RTMFP, which I think has streaming video over UDP, but currently it seems only available in Flash Media Server 4 and I think the price tags on those products would discourage my boss greatly :slight_smile:

You can not listen to the broadcast from UDP 8002 port on wowza media server