Telephony is a term denoting the technology that allows people to have long distance voice communication. It comes from the word ‘telephone’ which, in turn, is derived from the two Greek words “tele,” which means far, and “phone,” which means speak, hence the idea of speaking from afar. The term’s scope has been broadened with the advent of new communication technologies. In its broadest sense, the terms encompass phone communication, Internet calling, mobile communication, faxing, voicemail and even video conferencing. It is finally difficult to draw a clear line delimiting what is telephony and what isn’t.
The initial idea that telephony returns to is the POTS (plain old telephone service), technically called the PSTN (public switched telephone network). This system is being fiercely challenged by and to a great extent yielding to Voice over IP (VoIP) technology, which is also commonly referred to as IP Telephony and Internet Telephony.
Voice Over IP (VoIP)
Voice over IP (VoIP) refers to a way to carry phone calls over an IP data network, whether the public Internet or an organization’s own internal network. One of the primary attractions of VoIP is its ability to help companies reduce expenses because telephone calls travel over the data network rather than the phone company’s network.
There are various protocols that can be used to implement IP telephony including:
- Session Initiation Protocol (SIP)
- Real-timeTransport Protocol (RTP)
- Real-Time Transport Control Protocol (RTCP)
- Secure Real-time Transport Protocol (SRTP)
- Session Description Protocol (SDP)
What are IP phone systems?
IP phone systems work together with IP phones in order to send and receive digital signals. IP phone systems are composed of three essential parts that allow them to work and send and receive IP voice digital signals. An IP phone system is comprised of an IP phone (also known as a VoIP phone), and an IP PBX, or a VoIP private branch exchange. The way that these systems work is that they are connected to a VoIP service provider through a Local Area Network (LAN). IP Phone systems work by transmitting telephone calls over the Internet, in contrast to the way that traditional telephone systems work via circuit-switched telephony systems.
The IP Communications solution delivers feature-rich communications built specifically for small offices and enterprises. The Key features include:
- Easy-to-manage, plug-and-play functionality that makes adding new users and components quick and easy.
- Single box, which offers unified management, simplified installation, integrated mobility with dual mode and single-number reach, and fewer products to manage.
- Default system configuration immediately available.
- Integrated voice mail – including the Integrated Messaging with industry e-mail client applications.
- Power fail-over support.
- Wireless support – voice and data.
- Support for up to three sites.
- Integrated firewall.
- Support for Power over Ethernet (PoE).