[en] In this talk I discuss the results of a joint paper with Z. Kuznetsova, where the split-division algebras are introduced to construct generalized supersymmetries in different space-time signatures. In particular, in D=11 dimensions, it is shown that split-octonions allow to introduce a split-octonionic M-algebra which extends to the (6,5) signature the properties of the 11-dimensional octonionic M-algebras, only existing in (10,1) and (2,9) signatures. The three space-times above form a triality-related set of (split-)octonionic, eleven dimensional, spacetimes. (author)