Following on the same ideas Adam B. Levine discussed on P2P Connects Us around Token Controlled Access/Viewpoint, I got an idea for using Ripple's "trust line" feature to offer a similar, but different, model of access control.
What Is A Trust Line?
In Ripple, users can explicitly express "trust" to other users using a trust line. These trust lines are denominated with an amount and a 3-letter currency code. The purpose is to ensure that users never get stuck with a currency they don't trust (e.g. GoxBTC), or an amount of currency that is more than they're willing to trust the issuer for (e.g. 1,000,000,000 BitstampBTC). I've previously shown how this feature can be hacked to create a distributed reputation system. Now I would like to propose another hack: using trust lines to control access the same way tokens are already being used in the LTB forums.
How Does It Work?
Users register their Ripple accounts with LTB.com just as they registered their Counterwallet account. They sign a message with their Ripple private key to verify control of the account. LTB then issues the account trust lines for assets like "TFF" for The Founder Forum, "POD" for Podcasters Only, etc. Any account with a positive-value trust line denominated in any access asset from LTB's Ripple account will then be granted access to the given asset/ resource.
Why Do This?
Tokens can be transferred. Yes, they can be revoked if someone who they are transferred to misbehaves, but what if we don't want access rights to be transferred at all? When the party granting the access has the ability to explicitly "trust" people into their network, it's up to new participants to gain the trust required to gain access to the resource. No longer is access available to anyone who happens to be the highest bidder (unless the party granting access likes it that way, in which case they are in the position to set up a potentially lucrative toll booth).
We don't necessarily need trust lines to achieve exclusive, non-transferrable access; we don't even necessarily need tokens. Someone who has a limited resource that they'd like to grant others exclusive access to could simply create a whitelist of accounts that can access the resource - if the account can cryptographically sign a challenge message with the appropriate keys, they've got access. This calls into question the purpose of tokens to begin with, which, when looked at from a rational perspective, reveals the ability for access tokens to be transferred to be more a feature than a bug (as assumed with the use-case for trust lines described above).
Do you have any other ideas for how trust lines can be used, or why this idea would or wouldn't work? Leave a comment below to share your ideas and earn LTBcoin Proof of Participation points for your contribution.
Cover picture taken from Ripple Charts