Local or Global Radio Channel Blacklisting for IEEE 802.15.4-TSCH Networks?

The IEEE 802.15.4 Time Slotted Channel Hopping (TSCH) networks suffer considerably from the high interference caused by the presence of nearby external devices, such as from the presence of IEEE 802.11b/g/n Access Points. Frequency hopping and blacklisting of radio channels that temporarily or consistently present bad performance are the two main approaches to cope with interference and increase the chances of successful packet delivery. However, the blacklisting of a number of channels and the scheduling of transmissions so that two or more neighboring links do not use the same frequency at the same time is a challenging problem, since in \ieee TSCH many parallel transmissions may occur. Blacklisting algorithms may be applied either locally or globally in IEEE 802.15.4 networks. In this paper, we first present the weaknesses of a localized blacklisting solution presented in the literature for multi-hop networks, and we propose a new distributed solution to overcome these issues. Both analytical and simulation evaluation under heavy interference show the superiority of the proposed scheme. In particular, the packet delivery ratio is improved while achieving minimum delay.