Currently, RIOT does not support the 6TiSCH, which is the adaption of 6LoWPAN over 802.15.4 TSCH (time slotted channel hopping), which is advertised as a vast improvement over fixed-channel 6LoWPAN. This issue tracks the over-all steps that are needed in RIOT to run 6TiSCH.

• Feature request: support IEEE 802.15.4 frame version 2 #4858: Support IEEE 802.15.4 frame version 2
• Support the 6TiSCH joining procedure
• Support time slotted frame transmission
• ...

Meta: Given that 6TiSCH is a much sought-after topic that comes up regularly in 6LoWPAN discussions, something web-searchable should reflect the state of things here. (At the time of writing, searches of riot and 6TiSCH yield links to outdated presentations, external libraries mentioning OpenWSN integration and similar).