Bulk AlxTe100-x glasses (17 <= x <= 29) prepared by melt quenching method are found to exhibit threshold switching. The local coordination of Al probed by MAS NMR indicates that Al resides in Al-[4], ([51)]Al and Al-[6] environments. With the addition of Al, there is an increase in C-3(+) defect centers which largely influences the switching properties of Al-Te glasses. The presence of higher coordinated Al crosslinks the network and the network becomes rigid. The switching voltage, glass transition and crystallization temperatures are found to increase with the increase of Al concentration. This indicates that the crosslinking and the rigidity of the structural network increases by the addition of Al. A memory switching material undergoes structural change between amorphous and crystalline states meaning a large structural reorganization. In a highly crosslinked rigid network, structural reorganization becomes difficult and hence results in threshold switching. (C) 2016 Elsevier Ltd. All rights reserved.