WBAN MAC Layer as per IEEE 802.15.6 MAC specifications
This page on WBAN MAC layer describes IEEE 802.15.6 MAC layer basics.It covers MAC layer frames as per different WBAN PHY layers.
As per IEEE 802.15.6 standard, the nodes are organised into one or two hop star WBANs. A single coordinator or hub controls the entire operation of each WBAN network. The WBAN composed of one hub and multiple nodes. In a one hopped star BAN, frame exchanges occur directly between nodes and the hub of the BAN. In a two hopped extended star BAN, hub and a node exchanges frames through a relay capable node.
Figure depicts MAC frame which is composed of fixed length MAC header, MAC frame body(variable in size) and fixed size FCS.
Figure also mentions MAC header which is composed of frame control field, recipient ID, sender ID and BAN ID. It also depicts various fields carried in frame control part.
Like other standards, IEEE 802.15.6 WBAN also mentions type and subtype fields. Type field indicates type of the current frame while subtype field indicates subtype of the current frame. WBAN Frames are categorized into management, control and data frames.
The IEEE 802.15.6 WBAN supports the following communication modes.
• Beacon Mode with Superframe Boundaries
• Nonbeacon Mode with Superframe Boundaries
• Nonbeacon Mode without Superframe Boundaries
The WBAN supports the following access mechanisms.
• Random Access Mechanism-Covers slotted ALOHA and CSMA/CD depending upon the PHY mode(viz. NB, HBC and UWB).
• Improvised and Unscheduled Access Mechanism
• Scheduled and Scheduled Polling Access Mechanisms