# CloudFront and nDVR - Ramifications of Sessionless Wowza Origin **URL:** \ **Category:** Wowza Streaming Engine\ **Created:** [March 26, 2014, 3:16pm UTC](https://community.wowza.com/t/cloudfront-and-ndvr-ramifications-of-sessionless-wowza-origin/42521 "2014-03-26T15:16:59Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Shane\_H](https://avatars.discourse-cdn.com/v4/letter/s/a3d4f5/32.png) [@Shane\_H](https://community.wowza.com/u/Shane_H)\ **Post date:** [March 26, 2014, 3:16pm UTC](https://community.wowza.com/t/cloudfront-and-ndvr-ramifications-of-sessionless-wowza-origin/42521/1 "2014-03-26T15:16:59Z")
I’m trying to set up CloudFront for the first time (following [the guide here](https://www.wowza.com/docs/how-to-integrate-your-wowza-ec2-instance-with-cloudfront)) and have some questions about what all the fuss is about Wowza being sessionless. - It says _“URL query parameters in player requests aren’t supported. This includes wowzaplaystart and wowzaplayduration for VOD playback and wowzadvrplayliststart and wowzadvrplaylistduration for nDVR playback.”_ I took this to mean that the nDVR AddOn won’t work when using CloudFront (or possibly any other CDN which uses edge servers). Is this correct? - It also says _“If you want to use Wowza nDVR as an HTTP caching origin, you must also add this property to the **DVR/Properties** container.”_ This seems to contradict what I understand from #1 (which probably means I’m not really understanding). Why set up nDVR as an HTTP caching origin if it doesn’t work with CloudFront? - Then there is this note under “Creating the CloudFront distribution”: ---
**Author:** ![Richard\_Lanham](https://avatars.discourse-cdn.com/v4/letter/r/c68b51/32.png) [@Richard\_Lanham](https://community.wowza.com/u/Richard_Lanham)\ **Post date:** [March 26, 2014, 11:51pm UTC](https://community.wowza.com/t/cloudfront-and-ndvr-ramifications-of-sessionless-wowza-origin/42521/2 "2014-03-26T23:51:24Z")
Hi, Wowza nDVR with AWS Cloudfront is supported. There are steps in the basic [Cloudfront guide](https://www.wowza.com/docs/how-to-integrate-your-wowza-ec2-instance-with-cloudfront), but additionally, in this case I think you will have to enable forward querystrings because the nDVR playback url is appended with a querystring ?DVR When using nDVR and Cloudfront, and in other cases as well, it is best practice to set the nDVR WindowDuration of 2 hours or less. If the WindowDuration is longer or not set, you should use the [Playlist Request API](https://www.wowza.com/docs/how-to-use-wowza-ndvr-playlist-request-api). With forward querystrings enabled, you can use the start and duration parameters in your playback client to create a cache with that length, then subsequent clients will playback from that cache. For more complex requirements, different start and length parameters, there are ways using StreamNameAlias addon, but it gets a little complicated. Richard ---
**Author:** ![Yasuhiko\_Takano](https://avatars.discourse-cdn.com/v4/letter/y/ac91a4/32.png) [@Yasuhiko\_Takano](https://community.wowza.com/u/Yasuhiko_Takano)\ **Post date:** [May 14, 2018, 6:27am UTC](https://community.wowza.com/t/cloudfront-and-ndvr-ramifications-of-sessionless-wowza-origin/42521/3 "2018-05-14T06:27:40Z")
Hi, I am also using Wowza nDVR and Cloudfront. > When using nDVR and Cloudfront, and in other cases as well, it is best practice to set the nDVR WindowDuration of 2 hours or less. This practice is applied only to Wowza nDVR and Cloudfront ? or MUST to be applied to other CDN? (i.e. akamai) Thank you in advance. ---
**Author:** ![Yasuhiko\_Takano](https://avatars.discourse-cdn.com/v4/letter/y/ac91a4/32.png) [@Yasuhiko\_Takano](https://community.wowza.com/u/Yasuhiko_Takano)\ **Post date:** [May 14, 2018, 6:30am UTC](https://community.wowza.com/t/cloudfront-and-ndvr-ramifications-of-sessionless-wowza-origin/42521/4 "2018-05-14T06:30:04Z")
I would like to re-phrase question. When I use Wowza nDVR as Origin and akamai as CDN to deliver HLS, also nDVR WindowDuration should be set to 2hours or less ?