Mitel 6867i Administrator's Manual page 238

Mitel 6800 Series SIP Phone Release 4.2.0 Administrator Guide
You can enable the IP phones to use a default "basic" codec set, which consists of the set of
codecs and packet sizes shown above;
or
you can configure a custom set of codecs and attributes instead of using the defaults (see
"Customized Codec Preference List" below).
Note: The basic and custom codec parameters apply to all calls, and are configured on
a global-basis only using the configuration files or the Mitel Web UI.
AMR AND AMR-WB (G722.2) CODECS (LICENSED FEATURE)
Administrators can configure Adaptive Multi-Rate (AMR) and Adaptive Multi-Rate Wideband
(AMR -WB) codecs on the 6863i, 6865i, 6867i, 6869i, and 6873i IP phones. AMR/AMR-WB
codecs provide improved speech quality during calls due to wider speech bandwidth, and cover
both real-time transfers through Real-time Transport Protocol (RTP) and non-real-time transfers
through stored files. AMR supports eight narrowband speech encoding modes (0-7) with
bit-rates ranging from 4.75 to 12.2 kilobits per second (kbps). AMR-WB supports nine wideband
speech encoding modes (0-8), with bit-rates ranging from 6.60 to 23.85 kbps.
Note: AMR/AMR-WB codecs is a licensed feature on the SIP IP phones. To confirm
that the license is active, Administrators can view the license through the phone's Web
UI on the Licensing Status page. AMR/AMR-WB should be listed if the feature is
available to be used. If Administrators configure AMR/AMR-WB when there is no
license, the codec will be ignored and not negotiated.
Administrators can configure AMR/AMR-WB on the IP phones in the Customized Codec
Preference List on the Web UI or in the configuration files using the existing "sip customized
codec" parameter.
Optional parameters have also been created to configure this feature. Administrators can
enable the feature by using the "sip amr codec payload format", which specifies the payload
format for AMR/AMR-WB. AMR/AMR-WB can operate in either bandwidth-efficient mode (0)
or in octet-aligned mode (1), depending on the value configured. Administrators can also disable
the octet-align mode and still send the octet-align:0 header in the Session Description Protocol
(SDP) by using value (2) for the parameter. By default, the IP phones utilize bandwidth-efficient
mode.
Administrators can also specify the list of mode sets that the IP phones support and state the
preferred mode to use if multiple modes are supported by both sides, using the "sip amr codec
mode set" and/or the "sip amr wb codec mode set" parameters. If no modes are defined then
all codec modes are allowed for the payload type.
4-85