SVP algorithms and complexity
Lattice-based cryptography is based on the hardness of certain lattice problems (almost tautologically). The region marked &quot;crypto&quot; denotes the region of approximation factors $\gamma$ such that:

We know how to construct cryptographic primitives assuming the hardness of $\mathsf{SVP}_\gamma$
It is plausible that $\mathsf{SVP}_\gamma$ is hard (as there are not known poly-time algorithms).