class BlockchainStorage:
    def __init__(self):
        self.sharding = ErasureCoding(k=10, m=4)
        self.consensus = ProofOfSpace()
        self.encryption = AES256()

    def store_file(self, file_data):
        # ファイル暗号化
        encrypted = self.encryption.encrypt(file_data)

        # シャーディング
        shards = self.sharding.encode(encrypted)

        # 分散配置
        locations = []
        for shard in shards:
            node = self.select_storage_node()
            tx_hash = node.store(shard)
            locations.append((node.id, tx_hash))

        # メタデータをチェーンに記録
        return self.record_metadata(locations)

contract StorageContract {
    struct File {
        bytes32 hash;
        uint256 size;
        address owner;
        uint256 timestamp;
        mapping(uint => ShardLocation) shards;
    }

    function storeFile(
        bytes32 _hash,
        uint256 _size,
        ShardLocation[] memory _shards
    ) public payable {
        require(msg.value >= calculateStorageFee(_size));

        files[_hash] = File({
            hash: _hash,
            size: _size,
            owner: msg.sender,
            timestamp: block.timestamp
        });

        distributePayment(_shards);
    }
}

構成:
  ノード数: 10,000
  地理分散: 50カ国
  キャッシュ: エッジ自動

利点:
  - DDoS耐性
  - 検閲回避
  - 自動負荷分散

def permanent_archive(document):
    # IPFS統合
    ipfs_hash = ipfs.add(document)

    # Filecoin保存証明
    deal = filecoin.store(
        data=document,
        duration=100_years,
        replicas=5
    )

    # Arweave永続化
    tx = arweave.permanent_store(document)

    return {
        'ipfs': ipfs_hash,
        'filecoin': deal.id,
        'arweave': tx.id
    }

class ZKStorageProof {
    bool verify_possession(hash, proof) {
        // データ所有の証明（データ開示なし）
        return zksnark_verify(
            public_input=hash,
            proof=proof,
            verification_key=vk
        );
    }
};