  In this work we compare two recent multiparty computation (MPC) protocols for
private summation in terms of performance. Both protocols allow multiple rounds
of aggregation from the same set of public keys generated by parties in an
initial stage. We instantiate the protocols with a fast elliptic curve and
provide an experimental comparison of their performance for different phases of
the protocol. Furthermore, we introduce a technique that allows the
computational load of both protocols to be reduced at the expense of protection
against collusion tolerance. We prove that both protocols remain secure with
this technique, and evaluate its impact on collusion tolerance and the number
of rounds supported.
