Joi Ito's conversation with the living web.

RSS 2.0 has an interesting feature called enclosures. It basically lets you have a link in your RSS feed that points to a media file or something so that you can download it in advance so it plays without having to wait for it when you get to it. It's moving blogging to be more "push" than "pull", but that's a good thing for big files. It certainly fits my blogging/browsing style and makes a lot of sense in the context of RSS.

See Chris Lydon's special RSS feed for a very good example. Currently, PopHeadlines (.Net), Radio (Windows, Mac) and VOX Lite (Windows) support enclosures.

UPDATE: ChrisDodo on #joiito just mentioned a point that I'd missed. The bandwidth issues. I guess the aggregators are going to have to be smart and allow you to filter stuff so you don't end up with tons and tons of media files hogging your bandwidth.


Joi, umm, how to say this politely -- the UPDATE is not a concern. With syndication, you would unsubscribe if a channel had too much content.

Believe me, dear Joi, no sarcasm, this is a revolutionary technology. Unlike most of the things you flog which will never come to fruition, this one is a gem. It took Adam Curry's persisent pleading with me until I bothered to really consider the idea, and when I did, it was one of those brilliant things I wish I had thought of myself.

I hope you look a little deeper and give it some thought. You *can* understand this. Ignore the programmers who tell you they know better. They don't. Ask them if they've listened to even one of the Lydon interviews. How many have you listened to? If you haven't done them all, why not? Perhaps the RSS With Payloads vision explains it.

Have the guts to actually learn about it. So much work has gone into this. Finally we've solved the chicken-and-egg issue. Don't piss on it Joi. You wouldn't like it if I pissed on something you believed in. Think about it.

I just wish there were other attributes or meta-data that could get passed with these enclosures. And I wish there were extensions for Calendar Events, Resumes, Reviews, Recipes and other new forms of micro-content possible with RSS 2.0.

i think the concept of enclosures is simple yet brilliant. conceptually, i liken it to tivo for the web--pvr for rss but can go much further in its potential. what our current bandwidth limits in our web media experience, enclosures can give us a glimpse of what it can be like without such constraints. i see good things in allowing the client to take some bandwidth shackles off of the creativity of the content provider.

"Enclosures" (not sure why this term is used) in RSS at first indeed sound like a good extension to handle large files (mp3, avi, and so on) that puts the burden of content-delivery back on the client, although it does not necessarily mean that the bandwidth issue is a non-problem. If a client program schedules enclosure download for between 2 and 4 am, you are actually looking for users that leave their computer on at night. Even if they do, it does not mean they can access enclosed objects in real-time. Suppose during daytime, a user wants to read an RSS feed that just got updated and has an enclosure. Download all enclosures? That still means waiting. Run it according to schedule? That means you potentially download quite a large number of enclosed objects from several RSS feeds. In other words, the idea is good, but I think it needs more thought.

Dave, bandwidth *is* an issue from the standpoint of current broadpand policies. Comcast is sending out notices for people violating a limit *that they won't even tell you the size of*. I need a way to deal with that, unsubscribing is not an option.

So my aggregator needs a governor on the channels. I may want to read Scripting News, but go directly to the persons website for the audio cause he gets some juice for page hits. Or maybe he has a fatter pipe or has a different format. (How does RSS Enclosures handle multiple formats of the same content?) So I dont want to unsuscribe, just limit or stop the media feeds based on various criteria.

There is the possibility for abuse too. Would we keep our NYT feeds if they suddenly started putting in AV feeds in the stream? TiVo already does this for 'enhanced content', guess what is was last night at 2:54AM? An ad for a 'toothbrush sterilizer" -- WTF?! I own my TiVo and I have *no* opt out options or a 'no ads' setting. They take my hard drive space and have no recourse.

Remember that Joi did not think of this immediately. Why? Cause Japan has cheap, fat pipes all over the place. AMerica does not. We only have 35% broadband penetration and you have seen first hand what a PITA it is when good broadband goes bad.

I will take my enclosure limiting aggregator, thank you very much :)

i discussed this briefly "in channel" and pretty much decided not to swim into the muck on this one, but... y'know. someone has to.

that was the POLITE comment?


I have to agree with Adam Hill about the bandwith problem, that's why we created the enclosure extractor in such a fashion that users can set the filesize limit when they are "browsing" enclosures. As for the possibilities of enclosures.. their endless as far as I'm concerned.


And a good explanation by Marc of all the other cool stuff my binary thinking mind never considered might be useful in an enclosure.$730?mode=day

(Ironically as a comment on Dave's essay on why people hate him)


The perfect way for a client to download large RSS enclosures is by using a tool that only downloads in the background when the network bandwith isn't being utilized.

NuParadigm's DrizzleCast is a free podcast client for Windows that uses Microsoft BITS technology to download RSS enclosures using idle bandwith.

DrizzleCast version 1.1 was released today. Added the ability to view the progress of downloads as well as the ability to open the file once the download has completed. View the screenshots to see these new features in action @

Its exactly this sort of thing that really pisses me off! (That is, when I open a delicious feed in TABS within firefox.)

One of them is feeding me obnoxious audio content that I would normally not bother to listen to.

I then dont know which tab to close! Often it ends up being all of them. (All the good links go out with the one "bad" link.)

I am certain thhat various sites use this facility more to annoy than as a "service".

This points to a tiny flaw within firefox, ideally, the content would not open until the relevent tab was selected.

It potentially could also be used in a malicious way, in that a 'endless' file could be served up, just to waste the end users bandwidth. (If, for an audio file, it was purely silence, you wouldnt even know it was happening!

It is very annoying!

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Hi Folks, The general idea behind enclosures is still broadminded, some say yes, others say no, I say with some guidance and visionary thinking we can make enclosures something valuable. The options are endless, at some point I believe we can eve... Read More