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New Member

what is meant when using VoIP term?

I hear people referring to VoIP but am getting confuse about i'ts true meaning..

1. Is VoIP a call initiated on a PSTN then encapsulated on IP packets

2. Is VoIP a call initiated on an IP phone, thus no need for conversion to IP

3. Are VoIP routers all routers that handle voic packets?

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Re: what is meant when using VoIP term?

Both cases are VOIP, basically voice packets carrier over packet network.

New Member

Re: what is meant when using VoIP term?

VoIP=Voice Over IP, which is the process of converting an analog or digital voice signal that originated from either an end device (analog phone, PBX) or the PSTN and converting it to a digital stream, breaking that stream into manageable chunks, and transporting it to a destination inside IP packets. At the destination, the packets are decoded, and the original audio stream will be reassembled and sent out to a phone, pbx or back to the pstn.

A call that is initiated on an IP phone to another IP phone is still considered VoIP. Your voice enters the microphone of the handset as an analog signal, then it is sent to the Digital signal processor of the phone which converts voice to a digital audio stream, breaks it into manageable size chunks and encapsulates it into an IP packet. The IP packet is sent to the other phone, the procerss is reversed and an analog signal is played out of the speaker in the handset.

A true VoIP router is a router that does the actual processing of converting the analog or digital signal to an IP packet. Any router can then route the IP packet, without being voice-aware (keep in mind Qos). Almost any cisco router can do VoIP, from the 1700 series up....

Call Manager is actually considered IP Telephony. CM uses VoIP to transport the actual audio stream, but "Telephony" is all of the "extra" features that a phone system needs like Hold, Conference, Transfer, Voicemail, etc....

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