j_d, TDM is a royalty, therefore I assume it's paid the same way as Dell-bundled ETS. It's my understanding Dell pays Wave royalties monthly.
ERAS is different in that it's not royalty revenue. However, if ERAS is sold through Dell which it sometiomes is (vs. by Wave direct to the customer), it could be that cash (like royalties) also comes in the door from Dell on a monthly basis.