"Then don't tell them through Facebook."

And that's the point.

If a current offering such as Facebook is "not a solution that people like", then that creates an opportunity for a solution that people _do_ like.

Will that opportunity be exploited? If not, why?

I don't think any large, online social network used by lay-people can allow the kind of privacy control that you (and many others) want. The system just becomes too complex, and information leaks. I think that we will eventually adapt to this constraint.

You said: "I don't think any large..."

If someone only wants to tell something to some of their friends, and assuming "some" is not a large number, does the network have to be "large"?

If so, why?

For lay-people to know about and be comfortable using it, yes, I think it has to be a part of a large service.

There are ways to share secrets with a small number of friends online, but even among technical people, very few people do it. I can see that it's possible to create a service around, say, PGP encrypted messages, and I can even see abstracting out the technical details of it. (That is, not forcing the users to think about keys, instead saying "Tell us who you want to be allowed to know the secret" and making and distributing public-private keys on the fly.) But I think even that level of conceptual overhead is more than lay-people are willing to deal with.

You said: "I think it has to be a part of a large _service_."

My question was about the size of the _network_.

In any event, following your line of thought, do you think it's possible to have a many _small_, separate networks that were somehow part of a large service?

Regardless of your answer, does our solution have to be a "service"?

What if it is a "product" that creates small networks as overlays on a larger, existing network such as the one all your friends are connected to: the internet?

You said: "I can see that it's possible to create a service around, say, PGP..."

What if you could see that it's possible to create a service (or product, or both) around, say, a scheme that involved only a single shared password and a single shared encryption key? That is, each friend has to remember only two strings for each network to which she belongs, sort of like, say, a username and password.

What if you could see that such a scheme might not require logging on and logging out as frequently as a web-based service such as Facebook?

Would that change your thoughts at all?

You said, when referring to a PKI scheme like PGP: "But I think that [the] level of conceptual overhead is more than lay-people are willing to deal with."

I once thought the same thing about Amazon's S3 service. When I saw the Dropbox product, my thoughts changed.

Without reaching Facebook-caliber critical mass, what would such a service offer people to join? Just in case you wanted to tell them something? I mean, if you just want a small system for telling your friends things, use a mailing list.

Why is there a need for a new technological solution to this? If I want to tell a few people something secret, I'll send them an email, or, you know, talk to them. I don't see where the problem/opportunity is.

There may be one situation in which technology helps, which is when you want to discuss a secret while remaining anonymous. For that, we have 4chan, reddit, forums, IRC, etc.

ramchip, you are correct.

With respect to "telling something to some of your friends", and attempting to do so "privately", there are certainly ways to do this without using Facebook.

However, that was only a specific example I chose, in line with veb's example of telling people you rub lettuce on your face, to use to illustrate to scott a point about whether only large networks could be useful in order to stay in touch with a small number of people, i.e., your friends. In theory, I could use any online activity or any service/protocol as an example to illustrate what the "solution" (a small private network) aims to achieve.

Talking (VOIP e.g. SIP), smtp (email), IRC and http (web forums), to use your examples, are examples of services/protocols that can be run over a network. Of course it is not an exhaustive list.

You could run them over the open internet, i.e. a very large, public network (of networks).

You could also run them over a small private network to which only a selection of people belong, e.g., your friends.

In theory, anything you could do with your friends on Facebook you could also do with your friends on your own small private network.

Multiplayer games is something for which this idea of "being on the same network", all at the same time, is well-suited. This is not a new concept. It is a very old one. Consequently, it's time-tested.

But playing games is only one example of what you can do.

The internet supports many services.

Theoretically, so too can your smaller network.

An obvious difference between doing things on the open internet (Facebook) and doing them on your own network is: _privacy_.

You do not have to invite advertisers and countless others to your private network if you do not want to. Might this be important to some people? That is an open question.

_Privacy_, of the kind discussed in the Facebook context, is the goal which the "solution" we are discussing aims to address.

Not simply "private mesaging" but privacy in everything you do with your friends online.

Rest assured, even if such a solution did exist and could be shown to work (NAT and whatever other issues you might predict have been solved), all the Facebook-type user interface doo-dahs are noticeably absent.

As such, it is a non-starter for any friend who cannot use a command line, unless some very good user interface developers got behind it.