Use sessionid to sum all durations from PPV

I'm using sessionid to sum all durations of each client from PPV,
but I found that the sum duration number is not actual client play time.

Once video is played, PPV controller will receive a request which include sessionid and delta time, so far is OK.

The problem is after that requests send to PPV controller are always
{"ID":"30d48f63-a0b7-8756-fa9b-b296b84abcf8","Signature":"0FZqZm389LnKjM9uyQuu9g==","Puzzle":"e3343111-c512-5050-3744-0f8c41b641fe","PayPerViewInfo":{}}

No player information, but the video is actually still playing. Even I waited 10 minutes. So the duration I got was only from the first request, which is around 30sec.
I want to know why the requests (after the first one) send to PPV controller are without player information.
Is the duration means the progressive download time of a video, not the playing time？

Thank you in advance.

If you apply PPV for vod content and particularly for progressive download server is working with client only during client is downloading content from the server. So yes server count duration as download time in this case.
If you need more accurate duration for vod content please consider hls/dash for vod. this way player will not download all file at once so your will get more accurate session duration. If you need to see exact session time for given client with very high precision the only way to do that is to use DRM. This way DRM provider should have duration in seconds resolution as it approve playback.

Thank you. I tried audio-only HLS from MP3, refer URL: https://blog.wmspanel.com/2014/05/streaming-mp3-via-hls.html

The player don't download file at once but it still finished download almost around 30sec even the play will last for 10 minutes. And in the Daily stats , the "Connections" field is still categorized into "PD" --progressive download.
I don't know whether I'm done it right or "hls/dash for vod" is still kind of progressive download and server only record the download time.

If the latter is true DRM will be the last way I can take.

Hi if you add /playlist.m3u8 at the end of your vod URL you should see "HLS" in your daily stats report. If you see "PD" this means you still request "raw" progressive download.
If you cannot use hls please file a new ticket via httsp://wmspanel.com/help and provide hls url you have problem with

Thank you so much.
Now I can see "HLS" in my daily stats report, but it's still very short around 30sec. It seems to be the download time, but kind of solve my problem.
Thank you for the answers.