Cisco VoIP
Voice over IP (VoIP) is a set of technologies that seeks to replace traditional
analog voice services. There are three main compelling benefits to VoIP:
■ VoIP makes better use of network capacity. Traditional voice uses a
64-kbps circuit, even when it is not active, but VoIP can use much less
and no capacity when the line is not in use.
■ VoIP allows new and revolutionary features, such as the following:
— Integration of voice and data systems (so that operators get
customer information popped on to the screen when a phone call
arrives).
— Voice CODECs can improve sound quality (at the expense of
bandwidth).
— Integration with new clients. Instead of an analog phone, VoIP
clients can include television boxes, Personal Digital Assistants
(PDAs), cell phones, laptops, and so on.
■ VoIP can save money by avoiding toll calls.
IP telephony solutions include many pieces:
■ Internet Protocol (IP) phones
■ Analog phones connected to IP by a Gateway
■ Control and number resolution by a Gatekeeper
■ Conferencing capabilities provided by a multipoint control unit (MCU)
■ Applications, such as directories and product information that interface
with smart IP phones