BAN Policy Integrity — Merkle Tree

Policy Class ID

One Policy Class groups multiple policies. The Merkle Root Hash of all policies will be stored on Ethereum for this PC ID.

Add a Policy to this PC

Role (User Attribute)

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Doctor

🚑

Paramedic

💊

Nurse

🧑‍⚕️

Health Asst

🔬

Researcher

🏥

Manager

Location (STZone)

Department

Start Time

End Time

Active Days

Mon

Tue

Wed

Thu

Fri

Sat

Sun

Permitted Operations

✓READ ✓WRITE ✓ENABLE sensor ✓DISABLE sensor

Quick Presets

Rules Preview — ℜ1…ℜ7

ℍPolicy = SHA256( ℜ1 ‖ ℜ2 ‖ ℜ3 ‖ ℜ4 ‖ ℜ5 ‖ ℜ6 ‖ ℜ7 )

Click "Add Policy" to compute →

Policies in —

No policies added yet.

ℍPC Root = SHA256( ℍP1 ‖ ℍP2 ‖ … ‖ ℍPn ) — stored on blockchain

Add at least one policy →

Figure 15 — PC Merkle Root Hash Tree (paper Section 9.2)

Level 3 (Root) — PC Root Hash stored on Ethereum | Level 2 (Policies) — ℍPolicy = SHA256 of all rules | Level 1 (Rules) — Atomic fields: role, location, dept, time, days, ops

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Build a Policy Class in Tab ① first.

PC Root Hash to Store

Policy Class ID

PC Root Hash (ℍPC)

What Gets Stored — Algorithm 2 Step 1

Step 1PMU sends PC ID + PC Root Hash → Ethereum smart contract

Step 2Blockchain confirms block. Hash is now immutable on-chain.

Step 3Individual policies stay in local policy repository (this browser)

NoteOnly the Root Hash is stored — NOT individual policies. One hash per PC.

Update Existing PC Hash

Policy Class ID

New Root Hash

Read Hash from Chain (free)

No gas. No MetaMask popup. Just reads from Sepolia.

Policy Class ID

Algorithm 2 — STABAC Integrity Check

Simulates Steps 6–8: STABAC recalculates the PC Root Hash from current policies, then compares it to the hash stored on the immutable blockchain.

Policy Class ID

Recalculated Root Hash (from current policies)

Select a PC above →

Demo: Tamper Simulation

This simulates a rule being modified in the policy repository. Even one character change in one rule causes a completely different Root Hash — tamper detected.

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