# Inner product argument

Halo 2 uses a polynomial commitment scheme for which we can create polynomial commitment
opening proofs, based around the Inner Product Argument.

> TODO: Explain Halo 2's variant of the IPA.
>
> It is very similar to $\text{PC}_\text{DL}.\text{Open}$ from Appendix A.2 of [BCMS20].
> See [this comparison](comparison.md#bcms20-appendix-a2) for details.
>
> [BCMS20]: https://eprint.iacr.org/2020/499