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How the VoIP Phone works

Can you please explain me what is ip phone and how does it work and what are the things to be configured in the network to make it work and what are the network components are required ?


Re: How the VoIP Phone works

the traditional telephon system we used to use based on whats called TDM

while with IP telephony it is based on IP comunication, as any computer has an Ip address the telephon will has too, but the will be call control system that map the phone number to the assigned IP address in Cisco technology the Callmanger or the new version called univief communication manager will be the call control system, and with IP telephony the main carrier for the comunication is the IP/L3 and the cisco IP phon use sccp protocol for call signaling over tcp 2000 with CUCM once the call connected between two phones theough the CUCM the comunications between the two ip phones will be dirct with the need to the callmanager and it will be over UDP with automaticly negociated udp port number

this is in brief

what component you need

you need first a reliable infra stracture such as switches and better to be configureable and support QOS

QOS gives proirity to voice for example over other kind of traffic to garntee the delevery and avoid any delay or latency in real-time traffic delevry

and also you need call control system

in traditional phon systems(non-IP) called PBX

with cisco the new version is CUCM

which is based one a server

however if you have small site with less that 240 user you can use a router to achive the call processing called callmanager expres

also if you have multisite deployment in this case you need routers voice enabled to do a gateways job for you between sites

hope i was helpful in this

rate if helpful

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