Ledger Protocol

Immutability · Hash Chains · ChronoLock Math

The Ledger Protocol provides the cryptographic backbone of SignalNetwork. Every proof, interaction, claim, vote, and snapshot is hashed into an append-only chain that cannot be modified after the fact.

1. Hash Chain (Append-Only Ledger) Core

$$h_k = H(h_{k-1} \| \text{payload}_k \| t_k \| \text{sig}_k)$$
$H$ — cryptographic hash function (SHA-256 or equivalent)
$h_{k-1}$ — previous entry hash (chain link)
$\text{payload}_k$ — content hash of the event (artifact, mesh event, claim, vote, etc.)
$t_k$ — timestamp
$\text{sig}_k$ — digital signature of the authoring node
$\|$ — concatenation

2. Merkle Root (Batch Integrity)

For any set of entries (daily, weekly, or custom batch), a Merkle root provides a single hash that verifies the entire set.

$$\text{root} = \text{MerkleRoot}(h_1, h_2, \ldots, h_m)$$

Any single entry can be verified against the root without downloading the entire batch (Merkle proof).

3. ChronoLock Year Seal Core

At each year boundary (UTC), a seal locks the entire year's ledger.

$$\text{root}_\text{year} = \text{MerkleRoot}(\{h_k : t_k \in \text{year}\})$$

Next-Year Genesis Pointer

$$h_0^{(\text{new})} = H(\text{root}_\text{year} \| \text{"genesis"})$$

Each new year starts a fresh chain that cryptographically references the previous year's seal. The chain is continuous and verifiable back to origin.

Sub-Seals (Daily / Monthly)

$$\text{root}_\text{daily} = \text{MerkleRoot}(\{h_k : t_k \in \text{day}\})$$

Daily seals provide intermediate verification points without waiting for the yearly seal.

4. Proof Redaction (Right-to-Erasure) Core

In an append-only system, deletion is impossible. Redaction replaces content with a cryptographic stub while preserving chain integrity.

Redaction Entry

$$h_r = H(h_{r-1} \| \text{"REDACT"} \| h_\text{target} \| t_r \| \text{sig}_\text{owner})$$
$h_\text{target}$ — hash of the proof being redacted
$\text{sig}_\text{owner}$ — signature of the proof's authoring node (only the author can redact their own proofs)

Redacted Content Stub

$$\text{stub}(a) = H(\text{payload}_a \| \text{salt}_a) \quad \text{(content hash preserved, content destroyed)}$$

The stub proves the proof existed and when, but the substance is gone. The original hash chain remains valid — the redaction entry is appended, not inserted.

Consequential Proof Exception (Protocol 043)

Proofs flagged as consequential (Tier 1–4 under Protocol 043) cannot be redacted. The redaction function checks: if $\text{tier}(a) \in \{1, 2, 3, 4\}$ then $\text{REDACT}(a) = \text{DENIED}$. Consequential proof chains are permanent under the Survivorship Clause.

5. Consequential Proof Tier System (Protocol 043) Core

Protocol 043 defines four consequence tiers. Each tier has a minimum proof burden that must be met before the consequential action is authorized.

$$\text{Tier}(a) = \begin{cases} 1 \; (\text{CRITICAL}) & \text{if action involves death, permanent harm, or loss of liberty} \\ 2 \; (\text{SEVERE}) & \text{if action involves major financial harm or rights loss} \\ 3 \; (\text{SIGNIFICANT}) & \text{if action involves substantial but recoverable harm} \\ 4 \; (\text{MONITORED}) & \text{if action involves delegated decisions with escalation potential} \end{cases}$$

Tier-Based Proof Burden

$$\sum_{a \in A(c)} q(a) \cdot w(a) \geq \Theta_{\text{tier}(c)}, \quad |\{\text{witness}(a)\}| \geq k_{\text{tier}(c)}$$
Tier 1: $\Theta_1 = 10.0, k_1 = 5$ (highest burden, no time exemption)
Tier 2: $\Theta_2 = 5.0, k_2 = 3$
Tier 3: $\Theta_3 = 2.0, k_3 = 2$
Tier 4: $\Theta_4 = 1.0, k_4 = 1$

6. Fork Choice Rule V2

If conflicting chains exist (split-brain scenario), the canonical chain is the one with the highest cumulative proof weight.

$$\text{Canonical} = \arg\max_{\text{chain}} \sum_{k \in \text{chain}} \pi(k)$$
$\pi(k)$ — proof weight of entry $k$
Ties broken by earliest timestamp. This is not proof-of-work — it's proof-of-mind weight.

7. Practical Defaults

Hash function: SHA-256 · Daily seal job: 00:00 UTC · Yearly seal: Jan 1 00:00 UTC · Redaction requires owner signature + 24-hour cooling period · Consequential proofs (Tier 1–4): permanent, no redaction