REM: DOI + blockchain anchoring for Trillian tree roots — proposal & demo

[lawrencejohnreilly-creator]

Hi Trillian team. I’m Lawrence Reilly, author of the REM protocol Internet-Draft (DOI + blockchain anchoring for permanence). REM aims to make auditable ledger roots citable and permanently discoverable.

Why I’m writing: I believe Trillian is an ideal append-only ledger backbone for REM. I’d like to share a 1-page mapping (Trillian → REM DOI metadata → blockchain anchor) and a tiny demo repo so implementers can try this end-to-end.

Links

REM Internet-Draft (IETF): https://www.ietf.org/archive/id/draft-reilly-rem-protocol-00.html

REM GitHub (demo / repo): https://github.com/lawrencejohnreilly-creator/rem-protocol

Trillian repo: https://github.com/google/trillian

Proposed mappings / quick ideas

Use Trillian as the high-throughput append-only ledger; periodically anchor Trillian’s signed tree root into a public blockchain and register that anchor (root hash + metadata) with a DOI.

Store COSE/Trillian inclusion proofs (or pointers to them) inside the DOI metadata so archived artifacts are cryptographically linked to the audit log.

Runtime: clients verify inclusion proofs against Trillian. Archive: REM issues DOI + blockchain anchor for long-term citation and discoverability.

Ask: Would Trillian maintainers/contributors be open to a short 30-minute sketch session to discuss practical integration and a minimal demo plan? I can prepare the 1-page mapping and a small demo script beforehand.

I can prepare a 1-page mapping + a tiny demo repo and share them for a short sketch if anyone’s interested.

Thanks,
Lawrence John Reilly
lawrencejohnreilly@gmail.com
| GitHub: https://github.com/lawrencejohnreilly-creator/rem-protocol

[mhutchinson]

Hi Lawrence,

Is there a reason you're looking at Trillian for this over the modern replacement for append-only logs: Tessera?

From the top-level Trillian README:
"""
Trillian is in maintenance mode. The next generation of transparency logs uses Tiled APIs and are better supported by Trillian Tessera. We recommend that any new log operators first try Tessera.

Community contributions to Trillian are still welcome, but please file an issue and/or swing by the Slack first for discussion!
"""

As for the proposal, I could do with some help to see what problem it solves. The two options I see are:

1. Ensuring the log doesn't present split views: we have https://c2sp.org/tlog-witness as a solution for this
2. Ensuring that data in the log stays available even if the log misbehaves: your proposal is only to store pointers to the log, so if data is removed, this wouldn't help. https://c2sp.org/tlog-mirror is the strategy the log transparency ecosystem is heading in for increasing data availability.

Hopefully that's useful context.
Cheers,
Martin

[lawrencejohnreilly-creator]

Hi Martin, Thanks for the context and for pointing me to Tessera, that’s very helpful, and I’ll dig into it further since my initial focus was Trillian’s history with transparency logs. Trillian was brought to my attention by Robin Bryce in an email. The aim of my proposal is dual-layer permanence (DOI archival + blockchain timestamping), so artifacts remain verifiable and citable even if a log operator misbehaves or disappears. I see this as complementary to tlog-witness and tlog-mirror: while they address split views and availability, my approach anchors entries in decentralized and academic infrastructures for redundancy and cross-domain permanence. Do you see room for exploring how this could extend the existing witness/mirror strategies? Best, Lawrence

…

On Wed, Sep 24, 2025, 9:05 AM Martin Hutchinson ***@***.***> wrote: *mhutchinson* left a comment (google/trillian#3814) <#3814 (comment)> Hi Lawrence, Is there a reason you're looking at Trillian for this over the modern replacement for append-only logs: Tessera <https://github.com/transparency-dev/tessera>? From the top-level Trillian README: """ Trillian is in maintenance mode. The next generation of transparency logs uses Tiled APIs and are better supported by Trillian Tessera <https://github.com/transparency-dev/trillian-tessera>. We recommend that any new log operators first try Tessera. Community contributions to Trillian are still welcome, but please file an issue and/or swing by the Slack first for discussion! """ As for the proposal, I could do with some help to see what problem it solves. The two options I see are: 1. Ensuring the log doesn't present split views: we have https://c2sp.org/tlog-witness as a solution for this 2. Ensuring that data in the log stays available even if the log misbehaves: your proposal is only to store pointers to the log, so if data is removed, this wouldn't help. https://c2sp.org/tlog-mirror is the strategy the log transparency ecosystem is heading in for increasing data availability. Hopefully that's useful context. Cheers, Martin — Reply to this email directly, view it on GitHub <#3814 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/BXWZRNRT5CLZKWCONX6D2BT3UKJIJAVCNFSM6AAAAACHJD45AGVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTGMRYGMZDMMBTGE> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[mhutchinson]

That all makes sense. Our current priorities are launching our Tessera-based CT logs, Verifiable Indexes, Witnessing, and our transparency conference next month. We're unlikely to have cycles to assist with this in the near future, but you may have success looking for collaborators in https://transparency.dev/slack (or at the conference, should you be able to make it to Gothenburg!).

[lawrencejohnreilly-creator]

Hi Martin, Appreciate the clarity and direction. I understand the team’s current focus on Tessera-based CT logs, Verifiable Indexes, and Witnessing. I’ll join the transparency.dev Slack and keep Gothenburg on my radar as opportunities to explore collaborators who may be interested in extending these efforts with dual-layer permanence. Thanks again for the guidance, very helpful. Lawrence

…

On Wed, Sep 24, 2025, 9:20 AM Martin Hutchinson ***@***.***> wrote: *mhutchinson* left a comment (google/trillian#3814) <#3814 (comment)> That all makes sense. Our current priorities are launching our Tessera-based CT logs <https://github.com/transparency-dev/tesseract/>, Verifiable Indexes <https://github.com/transparency-dev/incubator/tree/main/vindex>, Witnessing <https://github.com/transparency-dev/witness/>, and our transparency conference <https://transparency.dev/summit> next month. We're unlikely to have cycles to assist with this in the near future, but you may have success looking for collaborators in https://transparency.dev/slack (or at the conference, should you be able to make it to Gothenburg!). — Reply to this email directly, view it on GitHub <#3814 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/BXWZRNU233PAQUXCH56XI7L3UKLCXAVCNFSM6AAAAACHJD45AGVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTGMRYGQYDMMBQGI> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[mhutchinson]

For completeness, leaving this reference to the last project I recall trying to integrate Trillian logs with blockchains: google/trillian-examples#359

I don't recall the history of it, so I can't provide any other commentary beyond what the commit history in that repo contains. Cheers.

[lawrencejohnreilly-creator]

Appreciate you pointing me to this, I’ll review the commit history and past work on Trillian/ blockchain integration to understand what was tried and where it left off. Thanks again for adding this reference.

…

On Wed, Sep 24, 2025, 9:29 AM Martin Hutchinson ***@***.***> wrote: *mhutchinson* left a comment (google/trillian#3814) <#3814 (comment)> For completeness, leaving this reference to the last project I recall trying to integrate Trillian logs with blockchains: google/trillian-examples#359 <google/trillian-examples#359> I don't recall the history of it, so I can't provide any other commentary beyond what the commit history in that repo contains. Cheers. — Reply to this email directly, view it on GitHub <#3814 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/BXWZRNVOQB4C6GL4J3XA6FT3UKMEHAVCNFSM6AAAAACHJD45AGVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTGMRYGQ2TKNJXGY> . You are receiving this because you authored the thread.Message ID: ***@***.***>