TESSERA
TESSERA by D3TN

DTN-native data substrate

Data that survives
disconnection.

A high-level data API on top of BPv7 — local writes, causal sync, safe merge, resumable objects. We harness two decades of Bundle Protocol engineering and hand it to developers through an API they already know.

Documents Logs Objects

The idea

Apps speak objects, documents, and logs. The network speaks bundles. Tessera is the layer in between.

Two decades of work made the Bundle Protocol excellent — custody, naming, fragmentation, BPSec, contact-plan routing. Necessary, but not sufficient: modern applications don't write to sockets or endpoint IDs. Tessera gives them a northbound data API and carries it over BPv7 southbound.

Stack: applications speak objects/documents/logs to Tessera's northbound API; Tessera carries them southbound over BPv7 (uD3TN, ION, HDTN).

Convergence

Replicas diverge while disconnected — and converge on contact.

Tessera is a mosaic of tesserae: each node keeps editing on its own, offline. When a link opens, the pieces tessellate into one coherent surface. No central server, no locks, no conflict dialog, no lost writes.

Scroll — watch the two replicas merge.

Three primitives

Three shapes, one substrate.

Familiar surfaces — object stores, document collections, key-value, message logs — compose from three DTN-native primitives.

Two replicas diverge then converge to the same set after sync.

CRDT collections

Conflict-free shared state. Concurrent edits merge instead of overwrite — every replica converges, in any order.

Automerge / Yjs — plus a DTN transport and signed admission.

A file split into hash-named chunks described by a manifest, resumable across contact windows.

Content-addressed objects

Large artifacts named by the hash of their bytes. Resumable, integrity-checked, deduplicated — built for store-and-forward.

IPFS / CAS + CFDP — plus BPv7-native resumable transfer.

A chain of signed operations linked by causal parents, with a frontier marker.

Signed causal log

The spine under both: an append-only log of signed operations linked by causal parents. Admitted once, authenticated.

Kafka / event-sourcing — plus a causal frontier and offline-first.

Feasible — today

We run it live.

Three nodes, A → B → C, with links that open and close. Edit a document on one and watch it CRDT-merge into the others as contacts open — multi-hop, store-and-forward, in the browser.

What's real: signed causal log, CRDTs (sets, registers, text), content-addressed chunked objects, idempotent admission — over simulated uD3TN AAP 2.0 message shapes. Vibe-coded with Claude as a low-cost build test-drive.

Let's make DTN accessible — Tessera hides the Bundle Protocol core and opens its benefits to applications.

An open-core substrate, plus a DTN application-development service. Built by D3TN.

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