In Wireless Sensor Networks (WSN), what is the primary routing protocol standardized by IETF for Low-Power and Lossy Networks (LLNs)?
RPL (RFC 6550) is a distance-vector routing protocol specifically designed for Low-Power and Lossy Networks (LLNs) operating over 802.15.4 links.
Which IEEE 802.15.4 frequency band is globally available as an unlicensed ISM band for Zigbee operation?
The 2.4 GHz ISM band is available for IEEE 802.15.4 worldwide, although regional 868 MHz and 915 MHz bands are also defined for specific regions.
What maximum raw data rate is supported by IEEE 802.15.4 in the 2.4 GHz frequency spectrum?
At 2.4 GHz, IEEE 802.15.4 supports a maximum raw data rate of 250 kilobits per second (kbps), optimal for sensor readings and control commands.
Which modulation technique is utilized by IEEE 802.15.4 in the 2.4 GHz ISM band to resist interference and multipath fading?
IEEE 802.15.4 uses O-QPSK combined with Direct Sequence Spread Spectrum (DSSS) at 2.4 GHz for robust noise resistance.
What major obstacle causes lack of interoperability across IoT systems, leading to the need for protocol standardization?
IoT standardization issues stem from vendor lock-in, protocol fragmentation, varying hardware capabilities, and non-unified data representation standards. All choices (A, B, C) contribute.