Specifies the type of ISDN BRI integrated U interface.
other - none of the following.
addOnU - An add-On card with ISDN BRI integrated U
interface.
onBoardU - An on board ISDN BRI integrated U interface
onBoardIntegUandSTPort - An on board BRI integrated U
interface with external S/T ports.
addOnIntegUandSTPort - An add-on card with ISDN BRI integrated
U interface and S/T port.