The Cisco ATA products are standards-based communication devices that deliver true, next-generation voice-over-IP (VoIP) terminations to businesses and residences worldwide. The Cisco ATA 190:

Protects existing telephone investment: The Cisco ATA 190 supports two voice ports (RJ-11 phone ports), each with its own independent telephone number, and a single RJ-45 10/100 BASE-T Ethernet port. Each port supports either voice calls or fax sessions, and both ports can be used simultaneously. This adaptor can use existing Ethernet LAN deployments.
Is cost-effective: The Cisco ATA 190 helps customers turn their analog phone devices into IP devices cost-effectively and is the preferred solution to address the needs of customers who connect to enterprise networks, small-office environments, or the emerging VoIP managed voice services and local services market.