You are deploying a ZigBee network based on the frequency band available for ZigBee deployment worldwide. What allowable action will do the most to…

The IEEE 802.15.4 standard, upon which ZigBee is based, specifies the 2.4 GHz Industrial, Scientific, and Medical (ISM) band as its only globally available frequency range. 802.11 (Wi-Fi) networks can operate in multiple bands, including 2.4 GHz and 5 GHz. When both ZigBee and 802.11 operate in the 2.4 GHz band, their signals can overlap and cause significant co-channel and adjacent-channel interference, degrading the performance of both networks. The most effective strategy to eliminate this interference is frequency separation. By moving all 802.11 communications to the 5 GHz band, the two networks operate in entirely different, non-overlapping spectrums, thus minimizing interference.

A. ZigBee is not specified to operate in the 6 GHz band; this band is used by newer 802.11 standards (Wi-Fi 6E/7).

C. ZigBee does not operate in the 5 GHz band; this is a primary frequency band for 802.11 (Wi-Fi).

D. This action would place both networks in the same 2.4 GHz band, which would maximize, not minimize, the potential for interference.

1. IEEE Std 802.15.4-2020, IEEE Standard for Low-Rate Wireless Networks. Clause 10.1, "Frequency bands and data rates," specifies the 2450 MHz band (2400–2483.5 MHz) as a basis for a globally available PHY layer, which is used by ZigBee.

2. Goldsmith, A. (2005). Wireless Communications. Cambridge University Press. Chapter 1, Section 1.4, "Wireless Spectrum," discusses the allocation of the 2.4 GHz ISM band for unlicensed use by technologies like 802.11 and Bluetooth, and the 5 GHz U-NII band for 802.11a/n/ac. This highlights the separation of bands as a core principle.

3. Sikora, A., & Groza, V. F. (2005). Coexistence of IEEE 802.15.4 with other systems in the 2.4 GHz-ISM-Band. In IEEE Instrumentation and Measurement Technology Conference Proceedings (Vol. 2, pp. 1786-1791). This paper analyzes the severe performance degradation when 802.15.4/ZigBee and 802.11/Wi-Fi operate concurrently in the 2.4 GHz band, establishing the need for coexistence mechanisms, the most fundamental of which is operating in different bands. DOI: 10.1109/IMTC.2005.1604473.