The PEC and PMC boundary conditions are the most straightforward to set up and use. Assigning the PEC boundary to one of the bounding walls of the solution domain simply forces the tangential component of the electric field to vanish at all points along that wall. Similarly, assigning the PMC boundary to one of the bounding walls of the solution domain forces the tangential component of the magnetic field to vanish at all points along that wall. For planar structures with a conductor-backed substrate, you can use the PEC boundary condition to designate the bottom of the substrate (the -Z Domain Wall) as a PEC ground. For shielded waveguide structures, you can designate all the lateral walls as PEC. Similarly to model shielded cavity resonators, you designate all the six walls as PEC.
[[Image:Info_icon.png|40px]] Click here to learn more about the theory of '''[[Basic_FDTD_Theory#Why_Does_FDTD_Need_Domain_Termination.3F | Perfectly Matched Layer Termination]]'''.
[[Image:Info_icon.png|40px]] Click here to learn more about '''[[Perfectly_Matched_Layer_Termination#Advanced_CMPL_Setup | Advanced CPML Setup]]'''.
=== Advanced CMPL Setup ===
{{Note|[[EM.Tempo]]'s default quarter wavelength offset for the domain box is a very conservative choice and can be reduced further in many cases. A offset equal to eight free-space grid cells beyond the largest bounding box usually give a more compact, but still valid, domain box.}}
[[Image:Info_icon.png|40px]] Click here to learn more about the theory of '''[[Basic_FDTD_Theory#Why_Does_FDTD_Need_Domain_Termination.3F | Perfectly Matched Layer Termination]]'''.
<table>