# Lag is acceptable, but can I sync streams in MPEG DASH/HLS across browsers & devices?

**URL:** <https://community.wowza.com/t/lag-is-acceptable-but-can-i-sync-streams-in-mpeg-dash-hls-across-browsers-devices/46230>\
**Category:** Wowza Streaming Engine\
**Created:** [November 18, 2015, 2:37pm UTC](https://community.wowza.com/t/lag-is-acceptable-but-can-i-sync-streams-in-mpeg-dash-hls-across-browsers-devices/46230 "2015-11-18T14:37:54Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Daan\_Nolen](https://avatars.discourse-cdn.com/v4/letter/d/a4c791/32.png) [@Daan\_Nolen](https://community.wowza.com/u/Daan_Nolen)\
**Post date:** [November 18, 2015, 2:37pm UTC](https://community.wowza.com/t/lag-is-acceptable-but-can-i-sync-streams-in-mpeg-dash-hls-across-browsers-devices/46230/1 "2015-11-18T14:37:54Z")

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So from what I understand here:

> [@Clarification on HLS/DASH config. properties in order to reduce lag of Live stream](http://community.wowza.com/t/-/45872):
>
> Hello, I have a problem with lag/delay on HLS is almost 60 sec and while on DASH I’ve managed to reduce it to 10 seconds. I’m streaming from Android with GoCoder (or other Android sources) and always using 1 second key frame interval (which I understand is the minimum since it expects an int) As suggested on these forum posts [How to configure Apple HLS packetization (cupertinostreaming)](https://www.wowza.com/docs/how-to-configure-apple-hls-packetization-cupertinostreaming%28iOS)[How To reduce delay in HLS](http://community.wowza.com/t/-/33651)[HLS From Live Camera](http://community.wowza.com/t/-/37404) I’ve tried reducing these HLS settings cuperti…

is that with chunked streams I have to accept (some) lag as opposed to RTMP/ RTSP, but is it then possible to have players on different devices/ in different browsers sync up?

I have a project where I add meta-content and web elements to a (live) stream; for instance I show (live) linkedin information, as a person gets into view; however, if the streams have different lags on different browsers then there is no telling when exactly I should show the overlay.

In flash I could communicate this with the netConnection, and RTMP was in it self incredibly accurate, but I’m unsure how to solve this issue in MPEG-DASH/HLS

I’m not even sure if it is something I should solve in wowza, or in my player(s)

any thoughts on this are appreciated

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**Author:** ![Paul\_Shields](https://sea2.discourse-cdn.com/flex002/user_avatar/community.wowza.com/paul_shields/32/390_2.png) [@Paul\_Shields](https://community.wowza.com/u/Paul_Shields)\
**Post date:** [November 20, 2015, 3:46pm UTC](https://community.wowza.com/t/lag-is-acceptable-but-can-i-sync-streams-in-mpeg-dash-hls-across-browsers-devices/46230/2 "2015-11-20T15:46:51Z")

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Hi,

RTMP/RTSP is really the best protocol for reduction in lag as well as more control over streams. HTTP streams that are chunk based will always have more latency. Having very small chunk duration targets is the way to go, but if you go too small then you may incur other issues such as choppy playback. This latency is also not just at the Wowza level but also at the player level as the spec may require minimum number of chunks before the player begins a stream. You can experiment with different [HLS](https://www.wowza.com/docs/how-to-configure-apple-hls-packetization-cupertinostreaming%28iOS) or [MPEG-DASH](https://www.wowza.com/docs/how-to-configure-mpeg-dash-packetization-mpegdashstreaming%28mpegdashstreaming%29) chunk settings to reduce lag but don’t expect RTMP performance.

Paul