voice over internet protocol plz help

[z_rainman]

hi everybody will i have a project and i must know how voip works form a phone to phone , as an example if iam in italy and i want to make an international call to france by what they called international calling card and these cards works by voip.. so what i need is that what is the core process , what's happend behing the stage .. when i use one of these calling cards.. in other words how this thing called voip works from home phone to other home phone located in other country... plz help me ......

best regards

 

[z_rainman]

no answer ,,

 

[Nigel Goodwin]

Why expect one when you ask a computer question in an electronics forum?.

 

[3v0]

The simplistic answer is that voice is sampled/digitized using an analog to digital converter, the samples are stored in packets, the packets are sent over the internet to the other end, the samples from the packets are used to recreate the original voice using a digital to analog converter.

For a better answer see https://en.wikipedia.org/wiki/VoIP

EDIT: As for the calling card, you are on your own.

 

[davidbball13]

just use skype it is free computer to computer and dirt cheep to call landlines
www.skype.com

 

[shokjok]

Just don't call the local emergency numbers from a VOIP phone. An recent incident in Canada highlights the mistakes made when you change addresses - it cost a child's life. Emergency calls should always be made from landline phones ( payphones, etc.).