The Cisco VG 224 is a Cisco IOS® high-density 24-port gateway for analog phones, fax machines, modems, and speakerphones within an enterprise voice system based on Cisco CallManager. Having these devices tightly integrated with the IP-based phone system is advantageous for increased manageability, scalability, and cost-effectiveness (see Figure 2). Commercial businesses can also use the Cisco VG 224 in conjunction with Cisco CallManager Express to effectively augment an Integrated Services Router (ISR) environment. Either topology environment will support business need for a high concentration of analog voice ports for modem calls, fax calls, and analog supplementary services (see Figure 3).