[rdfweb-dev] presence detection

Ben Hammersley ben at b...
Fri Jul 26 08:56:56 UTC 2002

Morbus Iff wrote:
>>This might be a result of too much sugar, but how about an element of
>><foaf:canChatWith>. The same of <foaf:knows>, but dynamically created
>>dependent on who is in the same IRC room (or similar) as you, or
>>available on your buddy lists.
>>Presence detection with built-in relationships would be interesting, I
>>think. especially, ah, in a mobile environment. Anyone else?
> Ben, could you give me an example of how this would work? I'm not sure I'm
> seeing the coolness of it all - how would some external client (reading
> your foaf file) use this information? Is it the same sort of ideas behind
> the ICQ image on websites, that says when you're online or not? Or perhaps,
> if you're in a channel, an aggregate list of :interests could be shown,
> giving a "map" of the interests of those you're chatting with?
> That'd be kinda interesting, actually.
> You've joined #swhack.
> Did you know 'sbp' wrestles 'ball lightning'?
> Or that 'Morbus Iff' doesn't like 'benhmm'?
> It'd be kinda like a greeter bot, only client side.
That's one use, certainly. A very cool one, too.
Let me tell you the thought process I was having. As background, I run a 
wireless access point for my street. I work at home, and from my desk, 
I can see the two cafes in range of the AP, and the hub I have between 
it and the gateway I've rigged. Being at home, I tend to rely on the 
kindness of strangers for conversation, and one neat thing is that when 
I see traffic on the wireless lan, I tend to wander over and say Hi. 
(The sort of people who can find the AP in the first place are usually 
interesting to chat with, and they invariably buy me coffee in exchange 
for the T1 line I let them use :-).

>From this, and using the wifi-enabled cafes in San Francisco and 
elsewhere, I thought it would be neat to have a FOAF setup for the 
access I offer. When they log on for the first time, I'd spin them 
through a FOAF'o'matic style thing, and then I could start making 
interesting correlations. There is already some "captive portal" 
software for wifi networks to enable me to do this (It's called NoCat.)

If that system was extended city-wide, I thought, you could search for 
people with specific interests, and locate them for a chat. So, I could 
be online in the centre of London, and say "hmmm, I wonder if there is 
anyone sat at a cafe near here looking to chat about RDF," and you could 
find them.

But then it occured to me that location is more complicated than that. 
At any one time I might be in my street in London, #swhack, rdfweb-dev, 
slashdot, my blogs, and on AIM/MSN/Yahoo/ICQ. All of which are valid 
locations from the point of view of conversation.

Now, once you start to take this out a degree of separation, the number 
of people potentially able to join in a conversation rises rapidly. I 
might be sat next to a person in London, who's online on a chatroom, 
where there is a person in a cafe in Marrakesh, who, in turn is AIMing a 
guy in Antartica. Ideas, nevertheless, will flow through.

So, anyway, in badly formed rdf we could have something like:

<foaf:mbox rdf:resource="mailto:ben at b...">

<foaf:location rdf:about="IRC://irc.openprojects.net/#swhack">
<foaf:mbox rdf:resource="mailto:morbus at d...">
<rdfs:seeAlso rdf:resource="http://www.disobey.com/foaf.rdf"/>

Along with some thoughts on the new mobile phones I've seen in Beta, 
with Java, GPS, and IRC built in, that's where I am so far...

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