Prestige 2302 Support Notes
Voice over IP (VoIP) is an emerging technology based on open IEEE standards. VoIP refers to the transmission of voice data over the Internet. Various protocols are available for voice transport. The most commonly used are SIP and H.323.
How does Voice over IP work?
In VoIP, voice data is sent digitally in discrete packets through the Internet, not through the traditional circuit switch of PSTN. To do so, an
Why use VoIP?
Traditionally voice data is transmitted using circuit switching. Since circuit switching is designed to carry voice, it does it very well. However, as broadband networks become a mainstream for network access and technologies have evolved, we don＇t want to confine ourselves to just using
In addition, it would take a much longer time, more effort and money to implement new features using circuit switching. Since the IP technology is a standard and various applications are available, it is easier and more
What is the relationship between codec and VoIP?
In order to send voice (analog signal) over IP, it first needs to be digitized. Codec is a technique used to digitize analog signal into digital signals and vice versa. There are various speech codec available for VoIP. Each codec has its advantages and disadvantages.
What advantage does Voice over IP provide?
VoIP provides advanced integration of text, video and voice in emails. This cannot be done using traditional circuit switching (PSTN).
What is the difference between H.323 and SIP?
H.323 and SIP are proposed by different groups. Session Initiation Protocol (SIP) is a standard introduced by the Internet Engineering Task Force in 1999 to carry voice over IP. Since it was created by the IETF, it approaches voice and multimedia from the Internet, or IP. Whereas H.323 emerged around 1996, and as an
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