Independent Basic Service Set (IBSS) allows two or more devices to communicate directly with each other without a need for a central device. This is known as Ad hoc mode where a peer to peer network between stations is formed without the need for an Access Point.
Basic Service Set (BSS) Wireless LAN is established using a central device called an Access Point that centralizes access and control over a group of wireless devices. All wireless devices do not communicate directly with each other but instead they communicate with the AP, and the AP forwards the frames to the destination stations. The Access Point manages the wireless network, advertises its own existence by broadcasting the Service Set Identifier (SSID) and any device that needs to use the wireless network must first send an association request to the Access Point. The Access Point can require any of the following criteria before allowing a client to join.
* A matching Service Set Identifier (SSID)
* A compatible wireless data rate
* Authentication credentials
After a client has associated itself with the Access Point, all communications to and from the client will traverse the AP.
The wireless coverage area of an AP is called the Basic Service Area (BSA), sometimes also referred as Wireless Cell. An AP can also be connected to a wired Ethernet Local Area Network through an uplink port connection unlike the Independent Basic Service Set in which the wireless network cannot be connected to the wired network.
The BSS is uniquely identified by the Basic Service Set Identifier (BSSID) which is the Layer 2 Mac address of the BSS access point. The wireless network although is advertised using an SSID which announces the availability of the wireless network to devices.
