voice-over-IP card that fits its routers. Cisco says all of its products can easily be equipped for voice and that voice packets can be guaranteed via quality-of-service (QoS) policy implementation on a Cisco-switched network. Lucent, Nortel Networks and Siemens offer similar strategies for providing VoIP gateway capabilities in some form or another. While gateways are the most popular VoIP products on the market -- available from at least 30 vendors --
