Sharovatov’s Weblog

Apple submitted HTTP Live Streaming spec to IETF

Posted in http by sharovatov on 2 May 2009

As I’ve blogged recently, nearly a year ago Microsoft proposed an approach for adaptive video streaming over HTTP – Smooth Streaming. As Microsoft didn’t apply for a patent for this technology, I was hoping to see the same beautiful approach implemented in modules for other web-servers, or even as web-applications – as it’s really easy to implement.

The mistake Microsoft did was that they didn’t submit this technology standard to IETF to make it RFC – and that’s what Apple’s doing at the moment.

Yes, I’m not mistaken – Apple copied the whole idea, called it HTTP Live Streaming and submitted to IETF.

Yes, there’re differences, but they are absolutely insignificant:

  • Apple spec suggests extending M3U format for a playlist – Microsoft uses SMIL-compliant ISMC client-manifest file (i.e. playlist)
  • Apple spec defines that the server creates the playlist – in Microsoft approach the encoder creates the playlist
  • Apple spec defines encryption for media files – Microsoft doesn’t

And the whole specification that’s been proposed is weird – I think they just wanted to submit it as soon as possible before Microsoft Smooth Streaming approach gets popularity and becomes de-facto standard.

Here’s what jumped at me when I was reading the spec:

  1. section 6.2.3. Reloading the Playlist file – why specify the expiration time of the playlist separately when HTTP 1.1 already has flexible methods for
    setting expiration time of the resource?
  2. encryption – what’s the purpose of encrypting media files when there’s HTTPS? And if there’s a purpose – HTTP already provides a place where encryption could be "plugged in" – Transfer-Encoding, why didn’t Apple just
    register another transfer-coding in IANA?
  3. EXT-X-ALLOW-CACHE – why add this if HTTP already gives flexible tools to control caching?

So as I see it – Apple was just a little bit in a hurry to propose this “standard” – looks like they took Microsoft idea, added some proprietary bits and bobs without thinking them through, didn’t use what HTTP natively provides but bravely called the draft “HTTP Live Streaming”.

Awesome.


Share :

About these ads

12 Responses

Subscribe to comments with RSS.

  1. progg.ru said, on 3 May 2009 at 9:18 am

    Apple подала заявку на HTTP Live Streaming копию Smooth Streaming от Microsoft…

    Thank you for submitting this cool story – Trackback from progg.ru…

  2. [...] final theory is that Apple is simply getting the jump on Microsoft, who proposed a similar adaptive video stream a year ago called Smooth Streaming but didn’™t [...]

  3. [...] final theory is that Apple is simply getting the jump on Microsoft, who proposed a similar adaptive video stream a year ago called Smooth Streaming but didn’™t [...]

  4. [...] final theory is that Apple is simply getting the jump on Microsoft, who proposed a similar adaptive video stream a year ago called Smooth Streaming but didn’t [...]

  5. [...] final theory is that Apple is simply getting the jump on Microsoft, who proposed a similar adaptive video stream a year ago called Smooth Streaming but didn’t [...]

  6. [...] final theory is that Apple is simply getting the jump on Microsoft, who proposed a similar adaptive video stream a year ago called Smooth Streaming but didn’t [...]

  7. Ansis said, on 10 November 2009 at 4:21 pm

    Besides from MacOs, Is this HTTP live streaming supported on Windows as well?

    Safari loaded the m3u8 playlist but it did not ask for audio contents. I was testing this out with WLIU-BK radio station.

    Thanks,
    Ansis

  8. sharovatov said, on 11 November 2009 at 7:07 pm

    I’m sorry Ansis, I have no idea if this technology was implemented in any Apple software. I know that it was widely critisized on HTTP Bis WG mailing lists, and I’m also aware that the original technology from which Apple “derived” (Microsoft Silverlight Smooth Streaming) is now getting serious popularity :)

    And in any case, I don’t think Apple will adopt this technology really soon – they seem to be only drafting it at the moment, so no wonder that Safari didn’t play the contents.

    Just as a matter of curiosity – were you trying to load a basic M3U playlist file in Safari or did you follow their “specification” to create the M3U?

  9. DostavkaTovarov said, on 23 January 2011 at 7:13 pm

    Доставка любых товаров, грузов и оборудования из Китая по всей России, таможенная очистка и сертификация. Объем от 10 куб.м. или вес от 2т. Многолетний опыт, оптимальные цены и сроки. 100% официально и надёжно! Ваш № телефона на почту или майл-агент dostavkatovarovСОБАКАmail.ru, или на ICQ 271-272-525 и мы Вам позвоним!

  10. Scoogrerb said, on 12 September 2011 at 9:29 am

    Do not quite understand what is at stake.

  11. Mr Stux said, on 29 August 2012 at 1:10 am

    AES-128 encryption is in the spec because transport layer encrypted content cannot be cached via CDNs. By using vanilla http to transfer encrypted chunks then CDNs (like Akamai) can be used to distribute the content without worrying about the content being in the clear

    And 3ivx technologies has now released an http live streaming client sdk for windows 8 and windows phone 8
    http://www.3ivx.com/technology/windows/metro/http_live_streaming.html


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Follow

Get every new post delivered to your Inbox.

%d bloggers like this: