  The Bloom filter (BF) is a space efficient randomized data structure
particularly suitable to represent a set supporting approximate membership
queries. BFs have been extensively used in many applications especially in
networking due to their simplicity and flexibility. The performances of BFs
mainly depends on query overhead, space requirements and false positives. The
aim of this paper is to focus on false positives. Inspired by the recent
application of the BF in a novel multicast forwarding fabric for information
centric networks, this paper proposes the yes-no BF, a new way of representing
a set, based on the BF, but with significantly lower false positives and no
false negatives. Although it requires slightly more processing at the stage of
its formation, it offers the same processing requirements for membership
queries as the BF. After introducing the yes-no BF, we show through
simulations, that it has better false positive performance than the BF.
