[xri] Top Ten XRI Requirements

[Drummond Reed <Drummond.Reed@onename.com>]

All:

In reviewing our strawman requirements document and Gabe's excellent
motivations document, I found myself wanting to boil it down to a "top ten"
list to help us focus on the essence, particularly as we approach the f2f.

I publish the following as a first attempt at doing this, and also as a
reminder to everyone of their homework assignment to send in to the list
either: a) any open issues relative to the requirements proposed so far, or
b) confirmation that you don't have any open issues.

=Drummond 

TOP TEN REQUIREMENTS FOR XRIs

1) Location-independence: the ability for an identifier to identify a
resource independent of its physical location on the network.

2) Application- and transport-independence: the ability for an identifier to
identify a resource independent of the application or protocol used to
access the resource. 

3) Persistence: the ability for an identifier to permanently identity the
same resource (i.e., not be reassigned).

4) Human and machine optimization: the ability for identifiers to be
optimized for either human readability/memorability or machine and network
efficiency.

5) Peer-to-peer: the ability for any resource to serve as its own root
identifier authority (i.e., no centralized or absolute authority required).

6) Unlimited federation: the ability for identifier authority to be
delegated to any depth. 

7) Context addressability: the ability for a resource to be identified in
the context of another resource.

8) Attribute addressability: the ability to identify the attributes of a
resource to any depth.

9) Version addressability: the ability to identify the versions of a
resource or its attributes to any depth.

10) Extensibility: the ability for the identifier scheme to be extended by
adding new sub-schemes without changing the underlying architecture.