In this section:

Use this object to specify Real Time Control Protocol (RTCP) options for the call. RTCP is used to report network traffic congestion data. Various actions (for example call disconnect) may be taken when congestion threshold settings are exceeded.

To View and Edit RTCP Options

On the SBC main screen, go to Configuration > Profile Management > Category: Media Profiles > Packet Service Profile > RTCP Options.

Select the desired Packet Service Profile from the drop-down list to view its respective RTCP Options parameters.

The RTCP Options window is displayed.

RTCP Options- default window

 

To enable RTCP, click the radio button next to Enable in the Edit RTCP Options window. The appearance of the window changes to the following:

Profile Management - Media Profiles - Packet Service Profile - Rtcp Options

 

The following fields are displayed:

Note

Except Rtcp, all the parameters described in the table below are visible only when Rtcp is enabled. See Figure 1 and Figure 2 above for the difference.

Packet Service Profile - RTCP Options Parameters

 
ParameterDescription
Rtcp

Specifies whether RTCP is supported for the call leg. The options are:

  • Disable (default)— Do not use RTCP for the call leg. 
  • Enable — Use RTCP for the call leg. When set to Enable the other RTCP-related options on this window become available.
Termination For PassthroughSpecifies RTCP termination behavior for pass-through calls. The options are:
  • Disable (default) — RTCP is relayed between the endpoints for pass-through calls if this option is set to Disable on both call legs.
  • Enable — Enable this option on a call leg to terminate RTCP sessions on that leg for pass-through calls. When enabled, generation of RTCP occurs on the configured leg irrespective of the RTCP configuration on the other leg. The following behavior applies to RTCP termination on the other call leg based on RTCP configuration:
    • When RTCP termination is enabled on one leg of a pass-through call and RTCP is enabled on the other leg, RTCP is also terminated on the other leg, regardless of the other leg's setting for Termination For Passthrough.
    • When RTCP termination is enabled on one leg of a pass-through call and RTCP is disabled on the other call leg, RTCP is not terminated on the other leg.
Enable RTCPFor Held Calls

If this option is enabled, the SBC ignores the configured RR/RS values in the Packet Service Profile and send RR/RS = 0 in the offer/answer and disables RTCP when the call is active. When the call is HELD, and a RE-INVITE is sent, SBC uses the configured values in the Packet Service Profile for RTCP bandwidth and enables RTCP. When the call is RESUMED, SBC again disables RTCP by sending RR/RS=0 in the RE-INVITE.

The value of RR ranges from 100-4000 and the value of RS ranges from 100-3000.

If this flag is disabled, the older behavior of SBC is applicable. Options are:

  • Disable (default)
  • Enable
RTCP Mux

When this option is enabled in the ingress or egress Packet Service Profile, RTCP-Mux (RTCP multiplexing) is enabled on the respective call leg of the SBC. This option is disabled by default.

This flag is applicable only for SIP Trunk Groups.

Packet Loss Threshold

Enter a value of 0, or a value in the range of 400-32767 to specify the Packet Loss Threshold (number of lost packets/100,000) which will trigger a Packet Loss Action. This parameter is required if Rtcp is enabled. When set to “0”, no packet loss inactivity detection is performed. The default value is 0.

Note

Configuring this parameter to a value less than 400 disables threshold detection, so be sure to use a value in the range of 400 to 32767 to enable threshold detection.

 

Note

The SBC calculates the packet loss rate as (number of packets lost/number of packets expected) x 100.

For every incoming call leg:

  • The SBC periodically (approximately after every 512 expected packets) calculates the packet loss rate.
  • The SBC also periodically (approximately after every 10 seconds) checks if the packet loss rate of the call is above the configured value for the parameter Packet Loss Threshold.
  • If the SBC detects that the loss rate has exceeded the threshold, it reports the difference to higher layer of services within the software stack.

This setting can be used in conjunction with  Media Peer Inactivity. To set a media peer inactivity timeout value, see the Media Peer Inactivity parameter on the Media Peer Inactivity page.

For an example configuration of this parameter, see Packet Service Profile - CLI page.

Rr Bandwidth

Specifies the RTCP bandwidth allocated to active data senders. The value ranges from 100 to 4000 and the default value is 250.

Rs Bandwidth

Specifies the RTCP bandwidth allocated for receivers. The value ranges from 100 to 3000 and the default value is 250.

Packet Loss ActionSpecifies what Packet loss action to take when packet threshold is exceeded. The options are:
  • None (default) — Take no action.
  • Packet Loss Trap — Generate trap.
  • Packet Loss Trap And Disconnect — Generate trap and disconnect.

RTCP Xr

Specifies control of RTCP-XR block processing and statistics collection

  • Disable (default) – retains existing default behavior (no statistics collection)
  • Relay – Allows end-to-end XR block relay (only) and statistics collection if end-to-end peer negotiation for RTCP-XR (a=rtcp-xr:voip-metrics) relay is successful; otherwise XR block is dropped.
  • Relay Or Terminate – Allows end-to-end XR block relay or per-leg termination if end-to-end negotiation for RTCP-XR relay is not successful (only one leg supports RTCP-XR). This setting guarantees XR block termination and statistics collection on any call leg where XR blocks are received.
Generate Rtcp For T140 If Not Received From Other Leg 

Use this flag to configure specific trunk groups to generate RTCP for text pass-through media streams.

This flag can be provisioned if RTCP is "enabled" under rtcpOptions.

  • Disable (default) – RTCP is not generated for T.140 media stream on this leg.

  • Enable – Enable flag to generate RTCP for T.140 media streams, provided RTCP is not received from other peer.

Make the required changes and click Save at the right hand bottom of the panel to save the changes made.