# Write a framework for SER (Sovernty Ephemerality Reproducibulity)

SER Framework Overview

The Sovereignty Ephemerality Reproducibility (SER) framework provides a structured approach for building systems that:

1. Sovereignty – give data owners full control over access, usage, and lifecycle.
2. Ephemerality – ensure data and computation artifacts are automatically retired after a defined lifespan.
3. Reproducibility – allow deterministic recreation of results from immutable provenance records, even after the original data has been purged.

1. Core Principles

2. Architectural Components

1. Policy Engine – validates access requests against owner‑signed policies.
2. Lease Manager – tracks TTLs, triggers automatic deletion, and notifies dependent services.
3. Provenance Store – immutable log of data lineage, transformation steps, and environment hashes.
4. Reproducible Executor – runs deterministic workloads inside sealed containers; records execution hash.
5. Revocation Service – processes owner‑initiated revocations, updates the provenance store, and propagates deletions.

3. Data Flow

flowchart TD
    A[Data Ingestion] --> B[Policy Engine]
    B --> C[Lease Manager]
    C --> D[Provenance Store]
    D --> E[Reproducible Executor]
    E --> F[Result Artifact]
    F --> G[Lease Manager (TTL)]
    subgraph Revocation
        H[Owner Revocation] --> B
    end

4. Sample Implementation (Python + Docker)

# ser_framework.py
import json, hashlib, time
from datetime import datetime, timedelta
from cryptography.hazmat.primitives import serialization, hashes
from cryptography.hazmat.primitives.asymmetric import padding

# 1. Owner‑signed policy
def sign_policy(policy: dict, private_key_pem: bytes) -> dict:
    priv_key = serialization.load_pem_private_key(private_key_pem, password=None)
    policy_bytes = json.dumps(policy, sort_keys=True).encode()
    signature = priv_key.sign(
        policy_bytes,
        padding.PSS(mgf=padding.MGF1(hashes.SHA256()), salt_length=padding.PSS.MAX_LENGTH),
        hashes.SHA256(),
    )
    policy["signature"] = signature.hex()
    return policy

# 2. Verify policy
def verify_policy(policy: dict, public_key_pem: bytes) -> bool:
    sig = bytes.fromhex(policy.pop("signature"))
    pub_key = serialization.load_pem_public_key(public_key_pem)
    policy_bytes = json.dumps(policy, sort_keys=True).encode()
    try:
        pub_key.verify(
            sig,
            policy_bytes,
            padding.PSS(mgf=padding.MGF1(hashes.SHA256()), salt_length=padding.PSS.MAX_LENGTH),
            hashes.SHA256(),
        )
        return True
    except Exception:
        return False

# 3. Create lease record
def create_lease(ttl_seconds: int) -> dict:
    expiry = datetime.utcnow() + timedelta(seconds=ttl_seconds)
    return {"expiry": expiry.isoformat() + "Z", "created": datetime.utcnow().isoformat() + "Z"}

# 4. Record provenance entry
def provenance_entry(data_hash: str, exec_hash: str, env_hash: str) -> dict:
    entry = {
        "data_hash": data_hash,
        "exec_hash": exec_hash,
        "env_hash": env_hash,
        "timestamp": datetime.utcnow().isoformat() + "Z",
    }
    entry["entry_hash"] = hashlib.sha256(json.dumps(entry, sort_keys=True).encode()).hexdigest()
    return entry

Dockerfile (deterministic build)

# Dockerfile.deterministic
FROM python:3.12-slim@sha256:3b2e5c9f8a1d4e6b9c7f2a1d5e8b9c0d1e2f3a4b5c6d7e8f9a0b1c2d3e4f5a6b
WORKDIR /app
COPY requirements.txt .
RUN pip install --no-cache-dir -r requirements.txt && \
    python - <<'PY'
import hashlib, sys, subprocess, json, os
# Pin all installed wheels to their hashes
for line in open('requirements.txt'):
    pkg = line.strip()
    subprocess.check_call([sys.executable, '-m', 'pip', 'download', '--no-deps', '--dest', '/tmp', pkg])
PY
COPY ser_framework.py .
CMD ["python", "-m", "ser_framework"]

Key points: the base image is referenced by its SHA‑256 digest, and the build script pins every wheel to its hash, guaranteeing reproducibility across builds.

5. Operational Guidelines

• Policy Rotation – rotate owner keys periodically; keep a revocation list in the provenance ledger.
• TTL Granularity – choose TTLs that balance privacy (shorter) with reproducibility (longer); store the TTL in the lease record.
• Audit Trails – expose a read‑only API that returns the Merkle proof for any provenance entry.
• Testing – run deterministic test suites that compare execution hashes against stored provenance to detect drift.

6. Example Use‑Case

A research consortium collects genomic samples. Each sample owner signs a policy allowing analysis for 30 days. The data is ingested, a lease of 30 days is created, and the analysis runs inside a reproducible Docker container. After 30 days, the lease manager automatically deletes the raw data, but the provenance store retains the hash of the input, the container image hash, and the execution hash. A future auditor can verify that the published results match the recorded provenance without ever accessing the original samples.

This framework equips you with the architectural blueprint, core code primitives, and best‑practice guidelines to implement SER in any data‑sensitive environment.