🧬 IoTIVP-Binary v1.0

Ultra-Light IoT Wire Format (TLV + Hash Footer)

IoTIVP-Binary defines the raw bytes-on-wire format for the IoTIVP ecosystem.
It is engineered for:

• Low-power devices (ESP32, RP2040, STM32)
• LoRa, BLE, UWB, WiFi, Sub-GHz
• Robotics & sensors
• Environments requiring integrity with minimal overhead

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📦 Packet Structure

+---------+------------+-----------+-----------+--------+--------+
| Header  | Timestamp  | Device ID | TLV Block | Nonce  |  Hash  |
+---------+------------+-----------+-----------+--------+--------+
   1B       2–4B         1–4B        variable    0–2B     4–8B

TLV = Type • Length • Value

This provides unlimited flexibility for custom sensors.

Type	Meaning	Value Format
0x01	Temperature	int16 fixed-point
0x02	Humidity	uint8
0x03	Battery	uint8
...	Extend freely	Custom

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🔐 Hash Footer

The final bytes are a BLAKE2s or SHA-256 truncated hash:

hash = blake2s(header + timestamp + id + tlv + nonce + secret)

Length: 4–8 bytes depending on profile.

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🧩 Python Example: Encode

from iotivp_binary import BinaryConfig, encode_packet

cfg = BinaryConfig(
    timestamp_len=2,
    device_id_len=2,
    nonce_len=1,
    hash_len=4,
    hash_alg="blake2s"
)

packet = encode_packet(
    header=0x01,
    timestamp=512,
    device_id=42,
    tlv_fields=[
        (0x01, (235).to_bytes(2, "big")),   # temperature
    ],
    nonce=7,
    cfg=cfg
)

print(packet.hex())

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🔍 Python Example: Decode

from iotivp_binary import decode_packet

decoded = decode_packet(packet_bytes, cfg=cfg)
print(decoded)

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📘 Features

• ✔ Ultra-low overhead
• ✔ MCU-friendly
• ✔ Cryptographic integrity
• ✔ TLV extensibility
• ✔ Deterministic layout for firmware

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🧱 Ideal For

• LoRaWAN payloads
• BLE/Bluetooth LE advertisements
• Robotics control sensors
• Satellite IoT links
• Mobile asset tags

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IoTIVP-Binary powers the entire IoTIVP integrity pipeline.