Configuring the Media System

Specifies the starting number for the RTP and RTCP port range.

The number of media port pairs used by the SBC system. 

To determine the last port number:

First Port Number + (2*Number of Port pairs) - 1.

Example:

Given: For starting port number (16384) and the number for port pairs is 600.
There are 600 pairs, meaning there are 1200 individual ports. 16384 + (1200-1) = 17583

Specifies the DSCP value for all RTP/RTCP packets from the SBC.

This is used whenever the SBC is connected to an external gateway that handles both data and voice traffic. When large volumes of data traffic as well as all VoIP traffic flow through the same router, a policy may be created that used the DSCP value of the media packets. The policy should be structured such that VoIP media packets receive higher priority and are expedited while other packets receive a lower priority and are queued. Network administrators should ensure that the non-VOIP packets are tagged with a different DSCP value on their network. Typically, the choice of DSCP for various kinds of packet flows in the network is determined by the network administrator and is configured on all routers within that IP network.

Specifies the audio source. Sources can be an uploaded music file (File) or live audio sourced from an FXS port (Live). Default option is File. If you select Live, the FXS Port option is displayed.

When uploading a Music file, the maximum file sizes are as follows:

• For SBC 1000: 1MiB
• For SBC 2000: 4MiB
• For SWe Lite: 1MiB

Music files must be one of the following formats:

• WAV
• PCMA (not supported in SWe Lite)
• PCMU (not supported in SWe Lite)
• PCM (not supported in SWe Lite)

For detailed information about how to upload a Music on Hold file, see Uploading Music on Hold Files - SBC SWe Lite or Uploading Music on Hold Files - SBC Edge.

A list of available FSX ports from which live audio may be sourced. The FXS Port field is only visible when Live is selected from the Music on Hold Service drop down list.

Note: Field applies to SBC 1000/2000 only.

Specifies the type of Line Echo Cancellation (standard or dual filter).

The standard LEC covers 128ms tail length (echo delay) and employs a 24ms sparse (non-zero coefficients) filter. The Dual Filter (background and foreground) Line Echo Canceller (LEC) covers 128ms tail length and uses 48ms sparse foreground filter. The Dual Filter is expected to provide better performance during double talk or slow echo-path change. Selection of the Dual Filter option may result in reduced channel densities.

Note: Field applies to SBC 1000/2000 only.

Specifies the level of echo cancellation employed by the SBC Nonlinear Signal Processor.

The default value is Mild. However there are two additional levels of echo cancellation, Strong and Aggressive. As each telephony system implementation varies, their echo characteristics similarly vary. Adjust the level of echo cancellation to suit your particular deployment. Too little cancellation may result in a persistent echo, too aggressive and you may experience voice "clipping".

Specifies whether STUN packets are generated from the SBC. The SBC sends STUN packets on the RTP and RTCP ports on all outbound IP call legs to open ports in the firewall (between the SBC and the Internet). The ability to enable/disable this option is for customers who do not have a firewall and would like a way to disable STUN packet generation. Two options are available: Enable (STUN packets are generated and sent by the SBC) or Disable (STUN packets are not generated). Default option: Enable.