|
IP telephone systems provide voice or multimedia communication
services through the use Internet protocol (IP) networks. These IP
networks initiate, process, and receive voice or multimedia
communications using IP protocol. These IP systems may be public IP
systems (e.g. the Internet), private data systems (e.g. LAN based), or
a hybrid of public and private systems.
VoIP (Voice over Internet Protocol) is an Internet phone service that bypasses your normal local telephone company. Internet VoIP service rings and has a dial tone just like any other telephone, but calls are routed over your Internet connection. Although it has been around for a little while (mostly for business use), its growing popularity may help lower the cost of phone communication for consumers and eliminate plain old telephone service (POTS) entirely. Unlike traditional analog telephone signals, which travel through a PSTN (public switched telephone network), VoIP digitizes the speaker's voice and sends it through either cable or DSL broadband Internet connections. An adapter connects your regular telephone to your Internet connection. Cable modems are the preferred choice for VoIP service. Since DSL uses a phone line for operation, you'll still need to keep an active traditional phone service, and some reviews note that call quality with DSL is not as good as with cable.
Call quality of VoIP is competitive and is a big determining factor in nearly all the VoIP reviews we read while preparing this report. In testing reported in a PC Magazine review, editors found voice quality nearly equal that of a regular phone and vastly better than that of a cell phone. However, PC World notes in its review that garbled words, clipped sentences, and dropped calls still do occur with varying degree depending on provider – especially on weeknights, when call traffic is heaviest, or when using your Internet connection for bandwidth-intensive tasks, like downloading video files. Consumer Reports notes that about 57% of survey respondents said Internet phone calls sounded at least as good as calls made on their traditional phone line.
|
