Which protocol defines WLAN signals operating in various frequency bands?

The IEEE 802.11 protocol is specifically designed for wireless local area networks (WLANs) and governs the communication standards for various types of wireless signals. It provides the specifications for radio frequencies used in WLANs, which allows devices to communicate wirelessly over different frequency bands, including 2.4 GHz and 5 GHz, among others. This protocol encompasses multiple amendments that address different aspects of wireless communications, including speed, distance, and security.

In contrast, IEEE 802.3 pertains to wired networking specifications, focusing on Ethernet technologies, and does not cover wireless communication. WPA2 is a security protocol used to ensure protection for wireless networks but does not define signal characteristics or frequency bands. ISO 27001 is related to information security management systems and is not concerned with network protocols or signal transmission. Therefore, the selection of IEEE 802.11 accurately reflects the protocol responsible for defining WLAN signals and their operation across various frequency bands.