Answers.Body: <p>This is very common for live broadcast. What's simpler than just sending a PGN file format?</p>
  
  <blockquote>
    <p>downloading whole new pgn every second is just unimaginable for me.</p>
  </blockquote>
  
  <p>Not really. While I don't claim myself a HTTP expert, your browser doesn't really need to do a new download. Good browser implementation should have a cache of your most recent PGN file. Only the HTTP response would need to be sent back. Please take a look:</p>
  
  <p><a href="https://stackoverflow.com/questions/20978189/how-304-not-modified-works">https://stackoverflow.com/questions/20978189/how-304-not-modified-works</a></p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-05-30T12:05:35.530Z
Answers.Text: Thank you for the link, it will be useful! It just appears to me that in peak time around let's say 3 hours of play on Olympiad it could take gigabytes of downloaded data per watcher and hour. Wouldn't the file be over 1MB? As one hour has 3600 seconds, with some normal refresh speed it just seems like gigabytes traffic per hour and watcher to me. And this is a lot, isn't it?
Answers.UserDisplayName: hoacin
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-05-30T12:06:38.637Z
Answers.Text: @hoacin I don't know the exact data requirement, but I don't think you'll need to re-download all PGN files every two seconds. BTW: high throughput webserver is quite common nowadays.
Answers.UserDisplayName: SmallChess
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-05-30T11:17:43.570Z
Answers.LastActivityDate: 2018-05-30T11:17:43.570Z
Answers.UserDisplayName: SmallChess
Body: <p>I was making live broadcast recent days and I'm quite surprised how it technically worked. We were downloading whole new PGN file every 5 seconds with format shown it the code below. Is this how things work by default, is this standardized way of accessing tournament games?</p>
  
  <p>Is it typical for major actions that access to games can be licensed/encrypted to avoid traffic from unknown entities?</p>
  
  <p>For actions with many boards and many watchers like Olympiad online traffic downloading whole new PGN every second is just unimaginable for me.</p>
  
  <pre><code>[Event "Nomina?ní turnaj"]
  [Site "?"]
  [Date "2018.05.29"]
  [Round "5.1"]
  [White "Babula, Vlastimil"]
  [Black "Plat, Vojtech"]
  [Result "0-1"]
  [BlackElo "2556"]
  [WhiteElo "2556"]
  [LiveChessVersion "1.4.6"]
  [ECO "D96"]
  
  1. d4 {[%clk 1:30:55]} d5 {[%clk 1:30:54]} 2. Nf3 {[%clk 1:31:03]} Nf6
  {[%clk 1:31:00]} 3. c4 {[%clk 1:31:10]} c6 {[%clk 1:29:19]} 4. Nc3
  {[%clk 1:30:57]} g6 {[%clk 1:28:47]} 5. e3 {[%clk 1:27:45]} Bg7 {[%clk 
  1:29:13]}
  6. Be2 {[%clk 1:27:05]} O-O {[%clk 1:29:35]} 7. O-O {[%clk 1:27:11]} dxc4
  {[%clk 1:25:13]} 8. Bxc4 {[%clk 1:27:06]} Nbd7 {[%clk 1:25:29]} 9. Bb3
  {[%clk 1:13:22]} Nb6 {[%clk 1:22:11]} 10. h3 {[%clk 1:08:06]} Bf5
  {[%clk 1:21:31]} 11. Nh4 {[%clk 1:02:41]} Be4 {[%clk 1:17:33]} 12. Nxe4
  {[%clk 1:02:24]} Nxe4 {[%clk 1:17:59]} 13. Qc2 {[%clk 1:00:24]} Nd6
  {[%clk 1:18:23]} 14. Nf3 {[%clk 0:58:11]} Rc8 {[%clk 1:18:48]} 15. Rd1
  
  ....
  
  and so on
  </code></pre>
  
Tags: <programming><pgn><online>
Title: Standard for receiving live chess broadcast
ThreadText: # Standard for receiving live chess broadcast
  
  (Asked by: username_0 on 2018-05-30)
  
  I was making live broadcast recent days and I'm quite surprised how it technically worked. We were downloading whole new PGN file every 5 seconds with format shown it the code below. Is this how things work by default, is this standardized way of accessing tournament games?
  Is it typical for major actions that access to games can be licensed/encrypted to avoid traffic from unknown entities?
  For actions with many boards and many watchers like Olympiad online traffic downloading whole new PGN every second is just unimaginable for me.
  [Event "Nomina?ní turnaj"]
  [Site "?"]
  [Date "2018.05.29"]
  [Round "5.1"]
  [White "Babula, Vlastimil"]
  [Black "Plat, Vojtech"]
  [Result "0-1"]
  [BlackElo "2556"]
  [WhiteElo "2556"]
  [LiveChessVersion "1.4.6"]
  [ECO "D96"]
  
  1. d4 {[%clk 1:30:55]} d5 {[%clk 1:30:54]} 2. Nf3 {[%clk 1:31:03]} Nf6
  {[%clk 1:31:00]} 3. c4 {[%clk 1:31:10]} c6 {[%clk 1:29:19]} 4. Nc3
  {[%clk 1:30:57]} g6 {[%clk 1:28:47]} 5. e3 {[%clk 1:27:45]} Bg7 {[%clk 
  1:29:13]}
  6. Be2 {[%clk 1:27:05]} O-O {[%clk 1:29:35]} 7. O-O {[%clk 1:27:11]} dxc4
  {[%clk 1:25:13]} 8. Bxc4 {[%clk 1:27:06]} Nbd7 {[%clk 1:25:29]} 9. Bb3
  {[%clk 1:13:22]} Nb6 {[%clk 1:22:11]} 10. h3 {[%clk 1:08:06]} Bf5
  {[%clk 1:21:31]} 11. Nh4 {[%clk 1:02:41]} Be4 {[%clk 1:17:33]} 12. Nxe4
  {[%clk 1:02:24]} Nxe4 {[%clk 1:17:59]} 13. Qc2 {[%clk 1:00:24]} Nd6
  {[%clk 1:18:23]} 14. Nf3 {[%clk 0:58:11]} Rc8 {[%clk 1:18:48]} 15. Rd1
  
  ....
  
  and so on
  
  **Tags:** programming, pgn, online
  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2018-05-30. Score: 2 | Accepted answer
  
  This is very common for live broadcast. What's simpler than just sending a PGN file format?
  
  > downloading whole new pgn every second is just unimaginable for me.
  
  Not really. While I don't claim myself a HTTP expert, your browser doesn't really need to do a new download. Good browser implementation should have a cache of your most recent PGN file. Only the HTTP response would need to be sent back. Please take a look:
  
  <https://stackoverflow.com/questions/20978189/how-304-not-modified-works>
  
  > **Comments:**
  > **username_0**: Thank you for the link, it will be useful! It just appears to me that in peak time around let's say 3 hours of play on Olympiad it could take gigabytes of downloaded data per watcher and hour. Wouldn't the file be over 1MB? As one hour has 3600 seconds, with some normal refresh speed it just seems like gigabytes traffic per hour and watcher to me. And this is a lot, isn't it?  
  > **username_1**: @username_0 I don't know the exact data requirement, but I don't think you'll need to re-download all PGN files every two seconds. BTW: high throughput webserver is quite common nowadays.  
  
  ---
  
  