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CODEC AND Protocols

i am pretty new to VOIP and IP Telephony.....i have two questions...first is in which scenario we are gonna use G.711 and in which scenario we are gonna use G.729.....and what is the bandwidth consumption of these two's......secondly if we havea FR relay WAN connection and our network will be called voice over fram relay or i m confuse abt whats the difference btween VOFR....VOIP.....etc....many thanks in advance

Hall of Fame Super Silver

Re: CODEC AND Protocols

G711 is typically used on LAN, where G729 which is compressed codec is used over WAN connections. If you have enough bandwidth then you may choose to use G711 over WAN as well. Aso to the consumption, it depends on Layer2 transport for example G711 call on ethernet without header or payload compression uses 87 kbps, G729 call over FR uses 27 kbps. Refer to this link:

As to the VOIP vs. VOFR question you can do both, if you simply use Frame Relay and run IP over it and voice on top of the IP network then you use VOIP over Frame Relay, if you run voice directly on top of Frame relay then you use VOFR. Typically these days most deployments utilize VOIP over Frame Relay or other WAN topologies.

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