Configuring AMR/AMR-WB Options

In this section:

Overview

This best practice provides guidance on configuring AMR/AMR-WB options from EMA in support of a Multimedia Telephony Service for IMS (MTSI) service as described on the page AMR and RTCP Enhancements.

This configuration is performed either on the PSX or on the SBC ERE platform (using either the SBC EMA or SBC CLI).

For the AMR/AMR-WB pass-through calls, the AMR/AMR-WB license is not required to install in the SBC.
For the AMR/AMR-WB transcoded calls, the AMR/AMR-WB license is required to install in the SBC.

To check the license information, execute the following command:

> show table system licenseInfo

SBC ERE Configuration

Creating Codec Entry

set profiles media codecEntry AMRWB-DEFAULT

Note

The Initial Codec Mode flag is supported by the following AMR/AMRWB codecs:

amrBandwidthEfficient
amrOctetAligned
amrwbBandwidthEfficient
amrwbOctetAligned

Configuring AMR Codec Entry

set profiles media codecEntry AMRWB-DEFAULT codec amrBandwidthEfficient activeCodecSet AMR-0-4.75kbps

set profiles media codecEntry AMRWB-DEFAULT codec amrOctetAligned activeCodecSet AMR-0-4.75kbps

Configuring AMR-WB Codec Entry

set profiles media codecEntry AMRWB-DEFAULT codec amrwbBandwidthEfficient modeSet AMR-1-8.85

set profiles media codecEntry AMR-WB codec amrwbOctetAligned modeSet AMR-0-6.6

PSX Configuration

AMR-WB Configuration

In the PSX Manager window, choose Codec Entry from the fourth drop-down box.
Figure 1: AMR-WB Codec Entry
To create AMR-WB codec, right click on the Selection Area.
Note
The Initial Codec Mode flag is supported by the following AMR/AMRWB codecs:
- amrBandwidthEfficient
- amrOctetAligned
- amrwbBandwidthEfficient
- amrwbOctetAligned
Figure 2: Selection Area

Select New from the resultant pop-up menu.
The Codec Entry window displays. Provide the Codec Entry name.
To configure AMR WB-Bandwidth Efficient codec, select G.722.2 (AMRWB-Bandwidth Efficient) from the Audio Encoding drop-down list.
Figure 3: AMR WB-Bandwidth Efficient Codec

or
To configure AMR WB-Octet Aligned codec, select G.722.2 (AMRWB-Octet Aligned) from the Audio Encoding drop-down list.
Figure 4: AMR WB-Octet Aligned Codec

Once the Audio Encoding is selected, the AMR-WB Options are visible.
Figure 5: AMRWB Options

The following parameters are displayed:

Table 1: AMR-WB Codec Options parameters

Parameter Description

Mode Change Neighbor

This flag restricts the mode change of an AMR-WB to the neighboring modes in the Active Codec Mode set. Neighboring modes are the ones closest in bit rate to the current mode, either the next higher or next lower rate.

If checked, the Egress offer/Ingress answer from SBC sets the Mode-Change-Neighbor value to 1.

If unchecked, change between any two modes in the Active Codec Mode set is allowed.

Initial Codec Mode as per 3GPP 26.114

This flag determines what is the initial codec mode of AMR-WB transcoded call, once the call is established.

If unchecked, AMR-WB call starts with the highest rate in the active mode set. If checked, AMR-WB call starts with a rate determined by the following algorithm:

If 1 codec mode is included in the mode-set, it should be the initial codec mode.

If 2 or 3 codec modes are included in the mode-set, the initial codec mode should be the codec mode with the lowest rate.

If 4 or more codec modes are included in the mode-set, the initial codec mode should be the codec mode with the second lowest rate.

By default, all the options of AMR-WB Mode Set are checked. To run the calls in a restricted AMR-WB Mode set, uncheck the modes that are not required in the Active Mode Set.
Figure 6: AMR-WB Codec Options for Restricted Mode Set
To run the calls in an unrestricted AMR-WB Mode set, select all the mode sets.
Figure 7: AMR-WB Codec Options for Unrestricted Mode Set
Click Save.

AMR Configuration

On the SBC EMA main screen, navigate to Configuration > System Provisioning > Category: Call Routing > PSX. The PSX manager window is displayed.
Figure 8: PSX Main Window
In the PSX Manager window, choose Codec Entry from the fourth drop-down box.
Figure 9: AMR-WB Codec Entry
To create AMR codec, right click on the Selection Area.
Note
The Initial Codec Mode flag is supported by the following AMR/AMRWB codecs:
- amrBandwidthEfficient
- amrOctetAligned
- amrwbBandwidthEfficient
- amrwbOctetAligned
Figure 10: Selection Area

Select New from the resultant pop-up menu.
The Codec Entry window displays. Provide the Codec Entry name.
Next, either configure AMR Bandwidth Efficient or Octet Aligned codec.
1. To configure AMR Bandwidth Efficient codec, select AMR Bandwidth Efficient from the Audio Encoding drop-down list.
  Figure 11: AMR Bandwidth Efficient Codec
2. To configure AMR Octet Aligned codec, select AMR Octet Aligned from the Audio Encoding drop-down list.
  Figure 12: AMR Octet Aligned Codec

Once the Audio Encoding type is selected, observe the displayed AMR options.
Figure 13: AMR Codec Options