The only fully plug & play supported gateways come from Audiocodes. There are different models, including the TP-260, which is a PCI card. sipXecs supports all Audiocodes gateways including FXS, FXO and T1/E1. Do not choose a gateway that offers both FXS and FXO ports on the same unit. Since these two port types are handled differently in sipXconfig, it is not a good choice.