Wenjing will present his thoughts about Sam Smith's strawman and his own proposal about TSP protocol design. If feedback is positive, then he has a suggestion for next steps.

Wenjing proposes that we develop a "consolidated position paper" between the proposals as a next step. His presentation slides are here: https://github.com/wenjing/Inter-Trust-Domain-Protocol/blob/main/ITDP%20Trust%20Spanning%20%26%20SPAC.pdf

Darrell O'Donnell suggested that a similar comparison with DIDComm V2 would be very helpful.

Sam Smith offered the following action item:

ACTION: Sam Smith to prepare a presentation on "sustainable privacy" for an upcoming TSPTF meeting.

ACTION: Drummond Reed to work with Sam Smith to schedule his presentation on "sustainable privacy".

APAC:

Wenjing ran through his presentation and proposal again for a smaller audience.

He said his first goal was to provide feedback on Sam Smith's presentation last week on his "SPAC" protocol. His second goal was to look at how it fit in an overall architecture.

Wenjing emphasized that he believes we should be defining a suite of protocols.

Jo Spencer agreed, and said that the parties to any relationship need to decide which protocols are appropriate for their needs.

On screenshot #3, we discussed that "surveillance privacy" over non-content metadata is very difficult to control precisely, and is not a "sliding scale", but a matter that has to be looked at in the context of any particular relationship/connection.

Wenjing emphasized the point that "the trust relationship and the communication channel are bootstrapped together in a recursively dependent spiral." Drummond Reed strongly agreed, and felt this was a fundamental principle of the overall design. Wenjing gave the example of using the core "control channel" to set up a separate streaming channel.

Neil Thomson said that this approach jives with his concept of a "trust ladder" that the parties are climbing.

Wenjing pointed out that Authenticity and Confidentiality are essentially binary (at least to a given level of cryptographic strength). Where the "higher trust level" needs to be negotiated is in the privacy aspect.

Jo Spencer asked if the "spiral" or "ladder" requires different channels or could be in the same channel. Wenjing clarified that it could be either.

In screenshot #8, Jo Spencer asked the question of how discovery works. Wenjing said that his proposal for the TSP does not handle discovery directly, but that can be handled in multiple different ways by separate protocols. 

In screenshots #11 and #12, Wenjing explained the following acronyms:

• ESP = Endpoint-to-Supporting System
• EIP = Endpoint to Intermediary System
• IIP = Intermediary-to-Intermediary System

The "ah-ha" for Jo, Drummond, and Neil at the end of this call is that the TSP suite of protocols in screenshots #11 and #12 are a dynamic spiral as discussed above. Any two parties can "walk up the spiral" as far as they need—to agree on the specific channels/protocols they need—to then conduct their business. What makes it all work is the SPAC foundation established at the base, relationship, messaging, and control layers.

ACTION: ALL TSPTF MEMBERS: If you were not able to attend Wenjing's presentation, please listen to the recording of the NA/EU meeting or the APAC meeting (the latter is probably easier to follow as it was a smaller group discussion with more time for clarifying questions) and/or review his slides before our next meeting (July 19).

We officially decided in last week's TSWG Plenary meeting to switch over to meeting every Wednesday (instead of 3-out-of-4 Wednesdays) starting in July.

However, we are officially entering summer vacation season. Drummond will be on vacation the next two weeks, as will several other TSPTF members, so we propose to have our next meeting on Wednesday July 19. (No action item needed as Judith did this in real time.)