SAS/OR: in LP/MIP-which method is used for detecting IIS?

[Germs]

I want to get some background information of SAS/OR, focus on infeasibility diagnostics using IIS (irreducible infeasible system/set). I wonder which method is used for getting IIS? filter or additive? Thank you!

[RobPratt]

Sensitivity filter and deletion filter.  See this section of the documentation.

[Germs]

Thank you so much!