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• Hung out to dry

  31 mai 2013, par Mans — Law and liberty

  Outrage was the general reaction when Google recently announced their dropping of XMPP server-to-server federation from Hangouts, as the search giant’s revamped instant messaging platform is henceforth to be known. This outrage is, however, largely unjustified ; Google’s decision is merely a rational response to issues of a more fundamental nature. To see why, we need to step back and look at the broader instant messaging landscape.

  A brief history of IM

  The term instant messaging (IM) gained popularity in the mid-1990s along with the rise of chat clients such as ICQ, AOL Instant Messenger, and later MSN Messenger. These all had one thing in common : they were closed systems. Although global in the sense of allowing access from anywhere on the Internet, communication was possible only within each network, and only using the officially sanctioned client software. Contrast this with email, where users are free to choose any service provider as well as client software, inter-server communication over open protocols delivering messages to their proper destinations.

  The email picture has, however, not always been so rosy. During the 1970s and 80s a multitude of incompatible email systems (e.g. UUCP and X.400) were in more or less widespread use on various networks. As these networks gave way to the ARPANET/Internet, so did their mail systems to the SMTP email we all use today. A similar consolidation has yet to occur in the area of instant messaging.

  Over the years, a few efforts towards a cross-domain instant messaging have been undertaken. One early example is the Zephyr system created as part of Project Athena at MIT in the late 1980s. While it never saw significant uptake, it is still in use at a few universities. A more successful story is that of XMPP. Conceived under the name Jabber in the late 1990s, XMPP is an open standard specified in a set of IETF RFCs. In addition to being open, a distinguishing feature of XMPP compared to other contemporary IM systems is its decentralised nature, server-to-server connections allowing communication between users with accounts on different systems. Just like email.

  The social network

  A more recent emergence on the Internet is the social network. Although not the first of its kind, Facebook was the first to achieve its level of penetration, both geographically and across social groups. A range of messaging options, including email-style as well as instant messaging (chat), are available, all within the same web interface. What it does not allow is communication outside the Facebook network. Other social networks operate in the same spirit.

  The popularity of social networks, to the extent that they for many constitute the primary means of communication, has in a sense brought back fragmented networks of the 1980s. Even though they share infrastructure, up to and including the browser application, the social networks create walled-off regions of the Internet between which little or no exchange is possible.

  The house that Google built

  In 2005, Google launched Talk, an XMPP-based instant messaging service allowing users to connect using either Google’s official client application or any third-party XMPP client. Soon after, server-to-server federation was activated, enabling anyone with a Google account to exchange instant messages with users of any other federated XMPP service. An in-browser chat interface was also added to Gmail.

  It was arguably only with the 2011 introduction of Google+ that Google, despite its previous endeavours with Orkut and Buzz, had a viable contender in the social networking space. Since its inception, Google+ has gone through a number of changes where features have been added or reworked. Instant messaging within Google+ was until recently available only in mobile clients. On the desktop, the sole messaging option was Hangouts which, although featuring text chat, cannot be considered instant messaging in the usual sense.

  With a sprawling collection of messaging systems (Talk, Google+ Messenger, Hangouts), some action to consolidate them was a logical step. What we got was a unification under the Hangouts name. A redesigned Google+ now sports in-browser instant messaging similar the the Talk interface already present in Gmail. At the same time, the standalone desktop Talk client is discontinued, as is the Messenger feature in mobile Google+. All together, the changes make for a much less confusing user experience.

  The sky is falling down

  Along with the changes to the messaging platform, one announcement stoked anger on the Internet : Google’s intent to discontinue XMPP federation (as of this writing, it is still operational). Google, the (self-described) champions of openness on the Internet were seen to be closing their doors to the outside world. The effects of the change are, however, not quite so earth-shattering. Of the other major messaging networks to offer XMPP at all (Facebook, Skype, and the defunct Microsoft Messenger), none support federation ; a Google user has never been able to chat with a Facebook user.

  XMPP federation appears to be in use mainly by non-profit organisations or individuals running their own servers. The number of users on these systems is hard to assess, though it seems fair to assume it is dwarfed by the hundreds of millions using Google or Facebook. As such, the overall impact of cutting off communication with the federated servers is relatively minor, albeit annoying for those affected.

  A fragmented world

  Rather than chastising Google for making a low-impact, presumably founded, business decision, we should be asking ourselves why instant messaging is still so fragmented in the first place, whereas email is not. The answer can be found by examining the nature of entities providing these services.

  Ever since the commercialisation of the Internet started in the 1990s, email has been largely seen as being part of the Internet. Access to email was a major selling point for Internet service providers ; indeed, many still use the email facilities of their ISP. Instant messaging, by contrast, has never come as part of the basic offering, rather being a third-party service running on top of the Internet.

  Users wishing to engage in instant messaging have always had to seek out and sign up with a provider of such a service. As the IM networks were isolated, most would choose whichever service their friends were already using, and a small number of networks, each with a sustainable number of users, came to dominate. In the early days, dedicated IM services such as ICQ were popular. Today, social networks have taken their place with Facebook currently in the dominant position. With the new Hangouts, Google offers its users the service they want in the way they have come to expect.

  Follow the money

  We now have all the pieces necessary to see why inter-domain instant messaging has never taken off, and the answer is simple : the major players have no commercial incentive to open access to their IM networks. In fact, they have good reason to keep the networks closed. Ensuring that a person leaving the network loses contact with his or her friends, increases user retention by raising the cost of switching to another service. Monetising users is also better facilitated if they are forced to remain on, say, Facebook’s web pages while using its services rather than accessing them indirectly, perhaps even through a competing (Google, say) frontend. The users do not generally care much, since all their friends are already on the same network as themselves.

  While Google Talk was a standalone service, only loosely coupled to other Google products, these aspects were of lesser importance. After all, Google still had access to all the messages passing through the system and could analyse them for advert targeting purposes. Now that messaging is an integrated part of Google+, and thus serves as a direct competitor to the likes of Facebook, the situation has changed. All the reasons for Facebook not to open its network now apply equally to Google as well.

• Launch Leech and the History of WMV

  14 septembre 2010, par Multimedia Mike — General

  I was combing through my programming archives again and came across an old Perl script called launch-leech.pl. This was a private script I used to maintain for the benefit of myself and a few friends. See, there was this site called Launch.com (URL doesn’t seem to do anything as of this writing but here’s the Wikipedia page). Purchased by Yahoo ! in 2001, Launch still maintained their independent branding. They also carried a lot of music videos, of which I am a huge junkie. launch-leech.pl was the tool I used to download the videos. This was particularly useful since I stubbornly clung to dialup internet access until mid-2004 and it would have been impossible to stream video at any decent quality (though there were 56k streams, so like I said– not possible at any decent quality).

  
  
  

  Technically
  I followed Launch.com for many years. To be honest, I only “followed” in that I figured out where their “latest videos” URL lived and regularly polled it. Each video had either a 6-, 7-, or 8-digit unique ID that could be plugged into the launch-leech.pl script which would then have a conversation with the relevant servers, determine the correct streaming URL with the highest quality, then download and save the URL by handing it off to an external program (first ASFRecorder, though I later switched to mmsclient).

  At one point, I even wrote a crawler that compiled an offline database of all the videos, their IDs and their metadata. I never thought of anything interesting to do with it, though.

  
  
  

  Windows Media Legacy
  During these glory days of leeching, Launch.com streamed using Windows Media. I admit, it’s a bit of a blur now — the site might have used Real or QuickTime, but I was obviously most in tune with the WM side. I remember when I first found the site circa 2000-2001, the videos were in MS MPEG-4v3, and the high quality bitrate was 300 kbits/sec. Eventually, Launch.com would stream WMV7, WMV8, and finally WMV9, with bitrates up to 700 kbits/sec. However, they never broke free of the 320×240 encoding resolution, which was frustrating. When I wasn’t able to notice any substantial difference between 300 and 700 kbits/sec, I felt it might be time to put those extra bits to work on a resolution upgrade.

  At least they were nice enough to re-encode a number of old videos using better codecs and bitrates with each revision, thus prompting me to scan through the site collecting updated video IDs for download.

  
  
  

  Epilogue
  I don’t clearly remember when I stopped visiting Launch.com. Video-wise, the web has been a blur of Flash video ever since about 2006. Meanwhile, I spent a lot of time collecting a bunch of music videos in the first half of the decade only to find that pretty much every version of every music video made since the dawn of time is available on demand thanks to YouTube. I have found that this phenomenon manifests in many areas as internet technology marches on.

  The Real Entertainment
  The launch-leech.pl tool represents a recurring pattern for me. I derive as much — if not more — entertainment from creating programs like launch-leech.pl (and implicitly reverse engineering something in the process ; in this case, a website) as I do from the intended entertainment media itself. I seem to have this issue a lot with games, too.

  Is this an issue for anyone else ? Am I the only one who would rather play with the box that a shiny toy comes packaged in ?

• Curator of the Samples Archive

  13 mai 2011, par Multimedia Mike — General

  Remember how I mirrored the world-famous MPlayerHQ samples archive a few months ago ? Due to a series of events, the original archive is no longer online. However, me and the people who control the mplayerhq.hu domain figured out how to make samples.mplayerhq.hu point to samples.multimedia.cx.

  That means... I’m the current owner and curator of our central multimedia samples repository. Such power ! This should probably be the fulfillment of a decade-long dream for me, having managed swaths of the archive, most notably the game formats section.

  How This Came To Be

  If you pay any attention to the open source multimedia scene, you might have noticed that there has been a smidge of turmoil. Heated words were exchanged, authority was questioned, some people probably said some things they didn’t mean, and the upshot is that, where once there was one project (FFmpeg), there are now 2 projects (also Libav). And to everyone who has wanted me to mention it on my blog— there, I finally broke my silence and formally acknowledged the schism.

  For my part, I was just determined to ensure that the samples archive remained online, preferably at the original samples.mplayerhq.hu address. There are 10 years worth of web links out there pointing into the original repository.

  Better Solution

  I concede that it’s not entirely optimal to host the repository here at multimedia.cx. While I can offer a crazy amount of monthly bandwidth, I can’t offer rsync (invaluable for keeping mirrors in sync), nor can the server provide anonymous FTP or allow me to offer accounts to other admins who can manage the repository.

  The samples archive is also mirrored at samples.libav.org/samples. I understand that service is provided by VideoLAN. Right now, both repositories are known to be static. I’m open to brainstorms about how to improve the situation.