1. A method of generating encrypted profiles for layout features, comprising: with a computer, receiving layout design and process profile data for a layout feature; partitioning the layout feature into a plurality of subdomains, the plurality of subdomains being associated with boundary nodes and internal nodes, the boundary nodes comprising points on boundary of the layout feature and points on conductors inside the boundary of the layout feature, the internal nodes being points inside the boundary of the layout feature; generating, based on the layout design and process profile data, a first model describing a first electric parameter relationship involving the boundary nodes and the internal nodes; generating, based on the first model, a second model describing a second electric parameter relationship involving the boundary nodes; and outputting the second model and location information of the boundary nodes as an encrypted profile for the layout feature.