AltiGen MAXCS 7.0 Update 1 ACM Administration - Manual (Page 332)

About the G.722 Codec
316 MaxCS 7.5 Administration Manual
Codec Negotiation
The logic for negotiating codec capabilities varies for various types of connection.
Codec Negotiation - Server to Client
With a server-to-client connection, the highest priority codec in the server's codec list that is supported by the
client will be assigned.
Following is an example of a typical setting for SIP devices on a LAN: G.722, then G.711 Mu-Law. This
hierarchy allows Polycom phones and the AltiGen IP-805 phone to connect via G.722. AltiGen IP phones will
connect with G.711.
Figure 182. Codec negotiation example: SIP devices on a LAN
The next example shows a typical setting for SIP devices on a WAN: First G.729, the G.723.1, and then G.711
u-Law. This hierarchy allows remote SIP devices to use the compressed codec G.729. Remote IPTalk
instances use G.723.1, and G.711 is used for other remote devices that do not support the other two codecs.
Figure 183. Codec negotiation example: SIP devices on a WAN
Codec Negotiation - Server to Server
With server-to-server connections, the responding device determines the codec from the common codecs that
both of the devices accept. Usually, the responding device selects the first preferred codec from among the
common list. We recommend that you assign a preferred codec on both servers, so that both incoming and
outgoing events use the same codec.
If you are not sure of the codecs supported by your SIP Trunk provider, then we recommend that you configure
a single codec (your preferred codec) for SIP Trunks.
About the G.722 Codec
MaxCS 7.5 supports the G.722 codec on Softswitch and on Cloud deployments. G.722 is a wideband audio
codec. The G.722 codec provides higher voice quality than more narrow-bandwidth codecs such as G.711.
MAXCS supports G.722 64 kbps only.
The CPU processing requirement for G.722 is similar to G.723 and G.729. It is designed to use the same
combo codec resources as G.723 and G.729.