ISO/IEC 17821:2015 defines the network specification for devices, which are operated on IEEE Std. 802.15.4-2011 PHY, capable to support the channel-hopped TDMA links of the DSME MAC of IEEE Std. 802.15.4e-2012, to provide low-cost communication network that allows reliable, deterministic-latency, and scalable wireless mesh connectivity.

This International Standard provides the following:

- DSME MAC link control;

- unbalanced cluster-tree based network formation;

- directional multiple grades mesh connection;

- link-path routing and data forwarding;

- link and link-path maintenance.