Which of the following is NOT a WLAN Service Set?

In the context of wireless local area networks (WLANs), a "Service Set" refers to a specific grouping of stations using a common communication protocol within a WLAN. There are mainly three types of WLAN Service Sets defined by the IEEE:

1. Independent Basic Service Set (IBSS) - This is a peer-to-peer network where devices communicate directly with each other without the need for a central access point.

2. Basic Service Set (BSS) - This is a network configuration that includes a single access point (AP) and its associated stations (clients). A BSS typically caters to a small group of users and allows them to communicate with each other through the access point.

3. Extended Service Set (ESS) - This integrates multiple BSSs into a larger framework, allowing for mobility and extended coverage. ESS uses multiple access points to allow seamless roaming while maintaining connectivity.

The term "WLAN," while it describes a wireless local area network as a whole, does not specifically categorize or describe a type of service set itself. Therefore, it is not classified as a WLAN Service Set. Understanding these definitions helps in grasping the differences between types of service sets and the broader WLAN environment.