Developed for small businesses the cisco spa8800 ip telephony gateway adapts to the needs of businesses that maintain their own on premise ip private branch exchange pbx or that want to add voice over ip voip to their legacy time division multiplexing tdm pbx or key system the spa8800 can be configured to be a fxo gateway for an asterisk open source pbx providing a versatile solution when conditions favor an external device powered by industry leading voip technology from cisco the s