Wireless Service Sets

Like wired networks, wireless networks have different physical and logical topologies. The 802.11 standard describes different service sets. A service set describes how a group of wireless devices communicate with each other.

IBSS - With an Independent Basic Service Set (IBSS), two or more wireless devices connect directly without an access point (AP). This is also called an ad hoc wireless network.

BSS - With a Basic Service Set (BSS), wireless clients connect to a wireless network through an access point (AP). A BSS is what we use for most wireless networks. The idea behind a BSS is that the AP is responsible for the wireless network.

ESS - An Extended Service Set (ESS) is composed of multiple APs using the same SSID. To create a larger wireless network, we use many APs and connect all of them to the wired network. The APs work together to create a large wireless network that spans an entire floor or building. The user only sees a single SSID, so they won’t notice whether we use one or multiple APs.

MBSS - A Mesh Basic Service Set (MBSS) is used bridge wireless traffic from one AP to another. Mesh APs usually have multiple radios. One radio is for backhaul traffic of the mesh network between APs; the other radio is to maintain a BSS for wireless clients on another channel. At least one AP is connected to the wired network. The other APs are meshed and are only connected through the wireless backhaul.