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Multicast Duplicate Packets On WOWZA Streaming

Hi There,
I’m trying to test redundancy multicast traffic from 2 sources and the same multicast group. EX. Wan link A source IP 10.10.10.1 multicast group 240.1.1.1/24 and Wan link B source IP 20.20.20.1 multicast group 240.1.1.1/24 (Same group, same content) send traffic to Switch (WOWZA Application connect this Switch) but WOWZA detect error Duplicate streaming and can’t play video streaming. I’m not sure the WOWZA application can detect Duplicate Packets and ignore them or not ??? (Customer needs redundancy source multicast).

Thank you.

This is our current recommended workflow for redundant streams in Engine: (I will assume HLS as the playback protocol.)

It is possible to configure redundant streams by delivering the same exact stream from two different Wowza servers configured as HTTP caching origin applications:

For this to work properly, there are two key facts to consider:

1 - The client session ID cannot be part of the generated chunklist.m3u8 and media.ts file names —> This is achieved by configuring the Wowza server(s) as an HTTP caching origin application, which is sessionless, as described in the articles above.

2 - The chunklists generated by each of the two servers will need to be in perfect sync, this is, “media001.ts” from origin server A needs to contain exactly the same video information as “media001.ts” from origin server B —> This can be achieved by setting property “cupertinoCalculateChunkIDBasedOnTimecode” to true, as described here: https://www.wowza.com/docs/how-to-configure-apple-hls-packetization-cupertinostreaming#additional-properties-for-live-streams

There is a second option as well and that is you can add Wowza CDN to your Streaming engine Account ( if you don’t have that already or if you do not have multiple engine servers already).

It is possible to configure redundant streams it would be possible to generate redundant HLS playback URLs when using Wowza Streaming Engine in combination with Wowza CDN, as described here: https://www.wowza.com/docs/how-to-stream-to-wowza-cdn

where you’ll notice that, when configuring the Wowza CDN Stream Target within Wowza Streaming Engine, you could choose “redundant” in the Destination Server section.

For example, if the final Wowza CDN HLS playback URL is something like: https://myStream.akamaihd.net/hls/live/abc123/7ec6aebe/playlist.m3u8

it will contain the following two chunklists:

Primary: https://myStream.akamaihd.net/hls/live/abc123/7ec6aebe/7ec6aebe_1_512000/chunklist.m3u8
Backup: https://myStream.akamaihd.net/hls/live/abc123/7ec6aebe/7ec6aebe_1_512000/chunklist.m3u8

You might want to have a look here as well: https://www.wowza.com/pricing/wowza-cdn