In contrast, DSPF models a detailed network of RC parasitics for every net. DSPF is therefore more accurate than RSPF, but DSPF files can be an order of magnitude larger than RSPF files for the same design. In addition, there is no specification for coupling caps in DSPF. DSPF is more similar to a SPICE netlist than the other formats. SPEF is an Open Verilog Initiative (OVI) — and now IEEE — format for defining netlist parasitics. SPEF is "not" identical to the SPF format, although it is used in a similar manner. Like the SPF format, SPEF includes resistance and capacitance parasitics. Also like the SPF format, SPEF can represent parasitics in detailed or reduced (pi-model) forms, with the reduced form probably being more commonly used. SPEF also has a syntax that allows the modeling of capacitance between different nets, so it is used by the PrimeTime SI (crosstalk) analysis tool. SPEF is smaller than SPF and DSPF because the names are mapped to integers to reduce file size.