The Cisco VG224 is a Cisco IOS Software-based high-density 24-port gateway for analog phones, fax machines, modems, and speaker phones within an enterprise voice system based on Cisco Unified CallManager. Having these devices tightly integrated with the IP-based phone system is advantageous for increased manageability, scalability, and cost-effectiveness. Commercial businesses can also use the Cisco VG224 with Cisco Unified CallManager Express to effectively augment an integrated services router (ISR) environment. Either topology environment will support business needs for a high concentration of analog voice ports for modem calls, fax calls, and analog supplementary services. The Cisco VG224 offers Cisco IOS Software manageability with 24 analog phone lines to be used as extensions to the Cisco Unified CallManager or Cisco Unified CallManager Express system in a very compact 19-inch rack-mount chassis.