[From Beginner to Expert - WLAN Common Terms] Section 15 - SSID, BSSID, and ESSID

Hello everyone,

Today, I'm going to talk to you about SSID, BSSID, and ESSID.

Service set identifier (SSID): a unique identifier that identifies a wireless network.

SSIDs are classified into the following types:

• Basic service set identifier (BSSID) is the MAC address of each VAP on an AP and helps quickly locate a VAP.

• Extended service set identifier (ESSID) is an identifier that identifies one or a group of wireless networks. When users search for available wireless networks on their STAs such as mobile phones, ESSIDs are displayed. In most cases, people are used to calling ESSID 'SSID'.

For example, in a company where a wireless network is deployed, employees can detect and access the wireless network "employee" using their mobile phones, and roam on the wireless network in the company. As shown in Figure 1, "employee" detected on mobile phones is the ESSID of the wireless network, that is, the commonly called "SSID". As employees move in the company, their mobile phones roam into the coverage areas of different APs. During the roaming, the ESSID does not change while BSSIDs change because the MAC addresses of VAPs on different APs are different.

Figure 1. ESSID and BSSID

Access users can perceive only the ESSID, but cannot and do not need to perceive the BSSID. The BSSID is mainly used in managing and maintaining a wireless network or locating wireless network faults.

That is all I want to share with you!