Re: The new charter is now in place

On 8/20/20 4:58 PM, Gregg Kellogg wrote:
> Perhaps we can describe mechanism for creating
> versioned/cached/optimized contexts, with a default managed by the
> group, along with a way to validate and update context versions. It
> should allow others to create their own context set, and how to achieve
> and measure the resulting compaction.

This mechanism exists in the current CBOR-LD implementation:

https://github.com/digitalbazaar/cborld/blob/main/lib/codecs/ContextCodec.js#L9-L11

The way it works today is that JSON-LD Contexts that are guaranteed to
not change (for some externally known reason, such as they're a part of
a W3C specification that locks the contexts in at particular releases
with a SHA-256 hash, for example). There can be 32,768 of these sorts of
contexts that are managed by the specification registry for "contexts
that won't change and are thus safe to use with CBOR-LD".

There is also another namespace consisting of 32,768 entries that are
application-defined. If an organization doesn't want to register their
frozen context globally, then they can just publish an
application-specific specification that specifies values from
32,769-65,535. There can be 32,768 of these sorts of contexts for
"application-specified contexts that won't change and are thus safe to
use with CBOR-LD".

What we don't do today for CBOR-LD is throw an error if one of these
types of contexts are NOT used. We can put that into the
specification... but remember, we don't throw in this case for JSON-LD
today either... so it would be a strange requirement to put on CBOR-LD
since we don't do that today for JSON-LD.

Contexts can change... that's been known for a very long time with
JSON-LD, and there are a variety of mitigations against that that are
deployed today (ship with frozen contexts and only use those, use
hashlinks or some other form of content-addressed identifier, use known
frozen URLs, etc.)

-- manu

-- 
Manu Sporny - https://www.linkedin.com/in/manusporny/
Founder/CEO - Digital Bazaar, Inc.
blog: Veres One Decentralized Identifier Blockchain Launches
https://tinyurl.com/veres-one-launches

Received on Friday, 21 August 2020 15:35:39 UTC