I have become a user of Brightkite, a service that provides situational awareness in the geographical context. Once its relationship to user location information sources such as Fire Eagle improve, it may become a very nice tool, especially in mobile use cases where location reporting may be partly automated.

But even if they add technical value in the growing world of geographically aware applications, theses services are actually not innovative at the functional level. For example, in the ham radio universe, APRS is already a great system for real time tactical digital communications of information of immediate value in the local area - which includes among other things the position of the participating stations. And there is also TCAS, which interrogates surrounding aircrafts about their positions, and AIS which broadcasts ship positions and enables the entertaining Vessel Traffic Services such as the one provided by MarineTraffic. All these radio based systems broadcast in the clear and are not satisfying the privacy requirements of a personal eventing service. But that problem has also been solved by the Blue Force Tracker which even though it is still a work in progress has already changed how a chaotic battlefield is perceived by its participants.

“Where am I, and where are my friends ?” is not only the soldier’s critical information - it is also an important component of our social lives, witness the thriving landscape of geosocial networking. Geographic location is a fundamental enabler : we are physically embodied and the perimeter of location based services actually encompasses anything concerning our physical presence. So we can’t let physical location services escape our control. Fire Eagle may be practical for now, but we need to make geographical information part of the basic infrastructure under our control and available on a standardized, open and decentralized basis. The good news is that much thoughts have already been invested into that problem.

Physical location is part of our presence, and as you may have guessed by now, this means XMPP comes to the rescue ! We have XEP-0080 - User Location, an XMPP extension which is currently a XMPP Foundation Draft Standard (implementations are encouraged and the protocol is appropriate for deployment in production systems, but some changes to the protocol are possible before it becomes a Final Standard - as good as a draft standard RFC and therefore good enough for early adopter use). It is meant to be communicated and transported by means of Publish-Subscribe or the subset thereof specified in Personal Eventing via Pubsub. It may also be provided as an extension of plain vanilla <presence/> but that is quite a crude way to do it compared to the Publish-Subscribe goodness.

The rest of the work is left to the XMPP client. Of course, the client can show them on a map, just as Brightkite currently does. But I can also easily imagine an instant messaging contact list on my PDA where one of the contact groups is “contacts near me”. I would love to have Psi do that…

With the profusion of tools, our online presence is all over the place… Here is a quick tour of where fragments of me can be found. I’m focusing on tools - I won’t list mere static pages (of which I still have a few dusty instances in various aging places). The goal of this article is to draw a quick taxonomy of the tools I’m using.

My original content publication outlets :

• My english speaking blog
• My french speaking blog
• My link blog
• My bookmarks
• My Photo Gallery
• My family blog
• My other family blog
• My favorite daily reads

Places where I echo my own content web feeds, track people and engage actively:

• Facebook
• Identi.ca
• FriendFeed
• Flickr

Places where I track people and participate :

• LinkedIn
• Brightkite
• Last.fm

Places where I infrequently participate :

• Dopplr
• Digg
• Stumbleupon

Places where I just echo my own content web feeds and/or status messages in case people there are tracking me there :

• Plurk
• Plaxo
• Rejaw
• Tumblr
• Technorati
• Kwippy
• Bebo
• Hi5
• Storytlr
• Koornk
• Multiply
• Swurl
• YouAre

Not only is this list not exhaustive, but I have not even bothered to count the forums and blogs where I lurk or contribute comments. Don’t think that I’m a normal user though : maintaining a watch over online tools is part of my trade, so I’m the sort of person who’ll create an account on every site in sight if just to take a look at it.

But in any case, the profusion is food for thought about meta-tools.

Open is everything - the rest is details. That is why we must take the best use cases of the closed social networking world and port them in the open. This is a lofty goal in all meaning of the adjective, but a surprisingly large number of potential basic components are available to cut the way short.

Friend of a Friend (FOAF) enables the creation of a machine-readable ontology describing persons, their activities and their relations to other people and objects. This concept is a child of the semantic web school of thought that has its origins about as far ago as the Web itself. In a narrower but deeper way, XFN (XHTML Friends Network) enables web authors to indicate their relationships to people simply by adding attributes to hyperlinks.

Microformats such as hCard, xfn, rel-tag, hCalendar, hReview, xFolk, hResume, hListing, citation, media-info and others provide a foundation for normalizing the information sharing. Some major operators are starting to get it - for example my LinkedIn profile contains hCard and hResume data. If you like hresume, take a look at DOAC while you are at it !

Some code is already available to process that available information. For example, identity-matcher is a Rails plugin to match identities and import social network graphs across any site supporting the appropriate Microformats. This code extracted from the codebase of dopplr.com and this is probably how Dopplr now supports import from other social networks like Twitter.

But part of the appeal of a social networking platform is how it empowers the user with control of what information he makes available, how it makes it available and to whom. So microformats are not sufficient : a permission management and access control system is necessary, and that requires an authentication mechanism. That naturally takes us to OpenID.

OpenID is a decentralized single sign-on system. Using OpenID-enabled sites, web users do not need to remember traditional authentication tokens such as username and password. Instead, they only need to be previously registered on a website with an “identity provider”. OpenID solves the authentication problem without relying on any centralized website to confirm digital identity.

The OpenID project is going even further than just authentication - authentication is just the surface. What OpenID really is about is digital identity management. OpenID Attribute Exchange is an OpenID service extension for exchanging identity information between endpoints. Although the list of attributes included in the OpenID Attribute Exchange schema does not match a nice collection of microformats, a process is defined to submit new attributes. And anyway, such a standard looks like a great fit to cover the need for keeping the user in control of his own content.

Finally, the social graph is the support for applications that must interact with the user’s information wherever it is hosted. That is why Google’s OpenSocial specification proposes a common set of API for social applications across multiple websites.

So a few technologies for social networking do exist, and they seem able to provide building blocks for an open distributed social networking. The concept of open distributed social networking itself has been in people’s mind for a long time. But until now only large proprietary platforms have succeeded in seducing a critical mass of users. Thanks to them, there is now a large body of information about the best practices and use-cases. What is now necessary is to think about how those use-cases can be ported into a decentralized open environment.

Porting a closed single provider system into an open distributed environment while equaling or surpassing the quality of the user experience is a huge challenge. But social networking and digital identity management are such critical activities in people’s life that the momentum behind opening them may soon be as large as the one that led Internet pioneers to break down the walls between networks.