 disturb" (no callers can reach you) and voice mail. For example, a company called PingTone describes this type of service that they offer (www.pingtone.com): The PingTone solution is based upon a comprehen- sive "managed service" concept whereby IP (Internet protocol) is provisioned to the desktop on a converged platform. The solution is comprised of network services such as local service, long distance, and Internet connec- tivity, a wide array of hosted PBX functions, unified messaging, and productivity-enhancing tools residing on the desktop through a voice client application which in- tegrates IP phone and PC functionality. In addition, one can buy or download software-only IP telephones (soft-phones) from companies such as VocalTech, Nortel, Ubiquity, Microsoft and SIPComm. These applications turn a PC into a telephone. In the case of VocalTech, they combine their software telephone with a service that not only lets you call other people with softphones, but through their network allows you to call virtually anywhere in the world. The Telecom Handbook dis 169 CONVERGENCE OF VOICE & DATA This chapter captures some of the history of the convergence of voice and data and the current environment, which continues to develop. To keep up to date we suggest the following websites: www.snowshore.com www.softswitch.org www.commweb.com 170 52 The Telecom Handbook CHAPTER 8 Interactive Voice Response Systems Interactive Voice Response (IVR) refers to the use of a touch- tone telephone to request information from a computer database. The touch-tone signals (sounds) are converted to digital signals understood by the computer. In turn, the digital signals coming back from the computer are converted into a voice that speaks the requested information. The idea is to eliminate the need for a live person to give out information. A well-designed IVR en- ables you to reach a live person if you need one. For example, most banks now offer you the capability to dial into a telephone number and enter your account number and passwor