The MAC header includes the MAC of the transmitter, receiver (can also be a Multicast or Broadcast MAC) and the BSSID. Until 11ax/Wi-Fi6, a radio needed to decode a frame header until the 802.11 MAC header begins. On the other hand, the BSS Color enables a Wi-Fi radio to determine quickly if an incoming frame is send from a device within the same BSS or not. You can also use a color as a filter within wireshark, although this will only give you the data frames for the specific BSS, no management or control frames! On the one hand, the BSS Color is an easy way to differentiate between multiple radios without looking at MAC addresses or (B)SSIDs. Figure 1: BSS Color in Beacon Usage of BSS Color Note: As the color is bound to the radio interface of an AP, the radio(!) uses the same color for all of its SSIDs. The BSS Color is then used in every 802.11ax Data Frame transmission. It is part of the HE Operation Extension Tag and also includes a Partial BSS Color (not part of this post) and a BSS Color Disabled field (explained later). Color AnnouncementĪn Access Point (AP) announces the color of its BSS in Beacons (see Figure 1 below), Probe and (Re-)Association Responses. However, a mapping of number to specific colors is not defined within 802.11ax, so each vendor and each tool can map a number to different colors. The term “color” is a bit misleading as it is rather a numeric number from 1 to 63, but the idea of a color is much nicer and easier to grasp.

Wi-Fi 6 devices are able to distinguish between frames that belong to their (associated) Basic Service Set (BSS) and Overlapping Basic Service Set (OBSS) by looking at the “color” of a frame. What’s in a name/MAC – if you can use colors?

Why does wireshark use different colors