The IVR components reside on circuit boards installed in- side a PC, using the PC processing and information storage capabilities. Some IVRs are separately built systems with a pro- prietary cabinet including circuit boards, processing capability and information storage space. The trend is toward standardized hardware, giving the IVRs more open architecture and lowering the cost. The IVR may work in conjunction with a telephone system, perhaps using an Automated Attendant, or callers may dial di- rectly into the IVR on outside telephone lines. The IVR is typically interfaced with a telephone system, enabling the IVR users to escape to a live operator, if necessary, by pressing "0." How The IVR Provides Information A telephone call comes through the PBX and reaches an an- nouncement asking the caller to enter or speak his five-digit account code. Or, the call may deliver an ANI or Caller ID, iden- tifying the caller. The PBX then repeats the information to the IVR and keeps the caller connected to the record located in the computer database. The caller then hears responses relating to his account through the IVR. If the caller wants to reach a live per- son, the PBX-to-host capability keeps the computer record attached to the call. The caller and the record arrive at the workstation of 172 The Telecom Handbook CHAPTER 8 Client/Server Model Linking computers together is best defined by the model called client/server. The client is the screen that you are looking at or the terminal where you are receiv- ing the information (such as your telephone). The server is the place from which the information you are viewing or hearing is coming. The term host is sometimes used to refer to a main- frame computer. The context in which we are using it here is to refer to the computer where the information for the IVR application resides. Another term might be IVR server. The expression PBX-to-host refers to the capabilities of a PBX to interface with a computer. IVRs are more likely to use a LAN (Local Area Network) and often OC