# New Space Lower-Bound Techniques for Streaming Algorithms

Is communication complexity (CC) the only known approach for streaming algorithms lower bounds? Are there any other techniques, even if conditional lower bounds?

In general, are we satisfied with the progress achieved via CC? Or seeking alternative techniques (even if conditional) would be an interesting direction?

For example, Datar et al. showed (Section 3) an $\Omega(\epsilon^{-1}\log^2 N\epsilon)$ lower bound for computing a $(1+\epsilon)$-approximation for the number of ones in the last $N$ bits of a binary stream.