Short integer solution problem

Short integer solution (SIS) and ring-SIS problems are two average-case problems that are used in lattice-based cryptography constructions. Lattice-based cryptography began in 1996 from a seminal work by Ajtai who presented a family of one-way functions based on SIS problem. He showed that it is secure in average case if ${\displaystyle \mathrm {SVP} _{\gamma }}$ (where ${\displaystyle \gamma =n^{c}}$ for some constant ${\displaystyle c>0}$) is hard in worse case scenario.

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