In this section:

These sections describe the configuration objects used for signaling. The following diagram depicts a basic signaling configuration.

Call Signaling Configuration Objects

 


Diameter Signaling Controls

Use this object to configure global diameter signaling controls.

Command Syntax

% set global signaling diamSigControls
	addSonusSpecificAVP <disabled | enabled>
	defaultCCF <ipAddress>
	enableRfApp <disabled | enabled>
	generateFailedEventAcr <disabled | enabled>
	maxACRretransmission <0-3>
	rfInterimAccInrvl <0-180>

Command Parameters

Diameter Signaling Control Parameters

Parameter
Length/Range
Description
addSonusSpecificAVP N/A

Enable this flag to send additional CDR information within Ribbon vendor-specific Attribute Value Pairs (AVPs) in Accounting-Request (ACR) messages over the existing Rf Interface.

  • disabled (default)
  • enabled

Note: Refer to Rf Interface Support for AVP details.

defaultCCFUp to 32 characters<ip address> – Specify the IP address to use as the default CCF realm configuration if CCF is not received in the PCFA. (default = 0.0.0.0).
enableRfAppN/A

Use this flag to enable the Rf Accounting application at the system level to send accounting information over Rf Interface. Refer to Rf Interface Support for feature details.

  • disabled (default)
  • enabled
generateFailedEventAcr N/A

Enable the flag to send an ACR for the failed event.

  • disabled (default)
  • enabled
maxACRretransmission0-3
<#> – Set the maximum number of ACR retransmissions to use if the SBC does not receive ACA (default = 3).
rfInterimAccInrvl0-180

<#> – Use this parameter to specify the interim account interval value to send when no interval is received in ACA. Set the value to 0 to not send interim record (default = 30).

Note: If ACA has a different value than rfInterimAccInrvl, this parameter is overwritten.

sigOnlyModeValueN/A

This global option controls whether the SBC is in signaling-only mode.

  • global – Places the SBC in signaling-only mode and automatically enables direct media on all trunk groups and all IPSPs.
  • off (default)

Note: You can only switch the SBC into or out of signaling-only mode when no active calls are present in the system.


Gateway Signaling Timers

This object allows you to configure the signaling timers for the gateway.

Command Syntax

% set global signaling gwSigTimers
   congRelDelay <delay in seconds>
   establish <timer value, in seconds>
   idle <idle time, in hours>
   keepalive <keepalive time, in seconds>
   retry <number of minutes to attempt to recover GW signaling link>
 
% show global signaling gwSigTimers
 
% delete global signaling gwSigTimers

Command Parameters

Global Gateway Signaling Timers Parameters

Parameter

Description

congRelDelay

Delay time (in seconds) before a release is issued for calls rejected due to congestion. (default=0)


establish

The Gateway Signal Channel Establishment Timer (in seconds.) This value applies to all signal channels. (default = 10).

idle

Idle time (in hours) for a GW Signaling Link May before it is taken down. (default = 0).

keepalive

The Gateway Signal Channel Keep-alive Timer (in seconds.) This value applies to all signal channels. (default = 3).

retry

Amount of time (in minutes) the SBC will continue to attempt to recover a GW Signaling Link as long as there are extant stable calls. (default = 60).


H.323 Signaling Timers

This object allows you to configure signaling timers for the node.

Command Syntax

% set global signaling h323SigTimers 
   establish <timer value, in seconds>
   t301 <timer value, in seconds> 
   t302 <timer value, in seconds> 
   t303 <timer value, in seconds> 
   t304 <timer value, in seconds> 
   t310 <T3timer value, in seconds10> 
   tcpConnect <tcpConnect> 

% show global signaling h323SigTimers
 
% delete global signaling h323SigTimers

Command Parameters

Global H.323 Signaling Timers Parameters

Parameter

Length/Range

Description

Default

establish

0-127

The H225 signal channel establishment timer (in seconds). Default value is 4.

4

t301

0-65535

The T301 call timer (in seconds).

180 seconds

t302

0-127

The T302 call timer (in seconds).

15 seconds

t303

0-127

The T303 call timer (in seconds).

4 seconds

t304

0-127

The T304 call timer (in seconds).

20 seconds

t310

0-127

The T310 call timer (in seconds).

10 seconds

tcpConnect

0-127

The TCP connect timer (in seconds).

3 seconds

Command Example

To display the global configuration of all h323SigTimers:

% show global signaling h323SigTimers  
   establish 33;  
   tcpConnect 77;  
   t301 444;  
   t302 33;  
   t303 22;  
   t304 33;  
   t310 33;

Max Num Transfers

Configure the SBC for the maximum number of transfers (10-100) allowed within a call; default is 10.

Command Syntax

% set global signaling maxNumTransfers <10-100>

Command Parameters


Max Num Transfers

ParameterDescription
maxNumTransfersSpecifies the maximum number of transfers (10-100) allowed within a call; default is 10.

Command Example

  • To configure maxNumTransfers, use the following example:

    % set global signaling maxNumTransfers 30
% commit
  • To display the maxNumTransfers, use the following example:

    • In the "configure" mode:

      % show global signaling maxNumTransfers
maxNumTransfers 30

    • In the "display" mode (when you exit the "configure" mode):

      > show table global signaling
maxNumTransfers 30;
messageManipulation {
    inputAdapterProfile  DD1;
    outputAdapterProfile DD1;
}
sipPeerOverloadControl {
    samplingPeriod  2;
    discardPeriod   2;
    stepDownGain    100;
    rejectThreshold 1;
}
sipSigControls {
    registrarSupportContactParam enabled;
    maxPduSizeValue              pdusize15kb;
}

SIP Message Manipulation

The SBC supports applying SIP message manipulation (SMM) profiles (SIP adaptor profiles) at the global level. Use the following parameters to assign SIP adaptor profiles that apply globally on ingress or egress. Refer to SIP Message Manipulation for more information on SMM.

Command Syntax

% set global signaling messageManipulation
      inputAdapterProfile <profile name>
      outputAdapterProfile <profile name>

Command Parameters


SIP Message Manipulation

ParameterDescription

inputAdapterProfile

<profile name> – Enter the name of a SIP adaptor profile to use globally on inbound messages.

outputAdapterProfile

<profile name> – Enter the name of a SIP adaptor profile to use globally on outbound messages.

Command Example

% set global signaling messageManipulation inputAdapterProfile globalInput 
% set global signaling messageManipulation outputAdapterProfile globalOutput
% commit


Signaling Only Mode

The SBC can be configured in a signaling-only mode so that the SBC participates in the exchange of signaling messages that set up a call but does not reserve or allocate any media resources for the session. The media component of the session is handled as direct media between the call participants.

Command Syntax

% set global signaling sigOnlyMode sigOnlyModeValue <global | off>

Command Parameters


Signaling Only Mode Parameter

ParameterDescription

sigOnlyModeValue

This global option controls whether the SBC is in signaling-only mode. The options are:

  • global - places the SBC in signaling only mode and automatically enables direct media on all trunk groups and all IPSPs.
  • off (default)

Command Example

% set global signaling sigOnlyMode sigOnlyModeValue global
commit


SIP IP Peer Stats

Use this flag to configure support for SIP IP Peer Statistics in the SBC.

Command Syntax

% set global signaling sipIpPeerStats <disabled | enabled>

Command Parameters


SIP IP Peer Status

ParameterDescription
sipIpPeerStats

Enable this flag to configure support for SIP IP Peer Statistics in the SBC.

  • disabled (default)
  • enabled

Command Example

  • To configure sipIpPeerStats, use the following example:

    % set global signaling sipIpPeerStats enabled
% commit
  • To display the sipIpPeerStats, use the following example:

    • In the "configure" mode:

      % show global signaling sipIpPeerStats
sipIpPeerStats enabled;

    • In the "display" mode (when you exit the "configure" mode):

      > show table global signaling
sipIpPeerStats    enabled;
maxNumTransfers 30;
sipPeerOverloadControl {
    samplingPeriod  2;
    discardPeriod   2;
    stepDownGain    100;
    rejectThreshold 1;
}
sipSigControls {
    registrarSupportContactParam enabled;
    maxPduSizeValue              pdusize15kb;
}

SIP Peer Overload Control

This object allows you to configure SIP Peer Overload parameters.

Command Syntax

% set global signaling sipPeerOverloadControl 
   discardPeriod <1-10 seconds> 
   rejectThreshold <0-50> 
   samplingPeriod <1-10> 
   stepDownGain <1-200>
% show global signaling sipPeerOverloadControl
  
% delete global signaling sipPeerOverloadControl

Command Parameters

Global SIP Peer Overload Control Parameters

Parameter

Length/Range

Description

discardPeriod

1-10

Discard period (in seconds) for the Peer Overload back-off algorithm. (default = 2).

rejectThreshold

0-50

Specifies the reject threshold (in rejects/sec) for the Peer Overload backoff algorithm. (default = 1).

samplingPeriod

1-10

Specifies the sampling period (in seconds) for the Peer Overload back-off algorithm. (default = 2).

stepDownGain

1-200

Specifies the step-down gain for the Peer Overload back-off algorithm. (default = 100).

displaylevel

1-64

To display different levels of output information in show commands.

Command Example

To display the global configuration of all SIP overload control:

% show global signaling sipPeerOverloadControl  
   samplingPeriod 2;  
   discardPeriod 1;  
   stepDownGain 44;  
   rejectThreshold 33;

SIP Signaling Controls

Use this object to configure SIP signaling control parameters.

Command Syntax

% set global signaling sipSigControls 
	egressRemoveEnudmi <disabled | enabled>
    egressRNParam <disabled | enabled> 
	loopDetectionFeature <disabled | enabled> 
	maxPduSizeValue <pdusize2kb | pdusize3kb | pdusize6kb | pdusize15kb | pdusize32kb | pdusize60kb> 
	multipleContactsPerAor <disabled | enabled>
	registrarSupportContactParam <disabled | enabled>
    send503DuringSwitchover <disabled | enabled>
	sendDeRegisterContactAsStar <disabled | enabled>
	sendSurrogateUnRegAfterReboot <disabled | enabled>
	suppressErrorInfoHdr <disabled | enabled>
	surrogateRegisterPacingTime <0-10000>
	ucidNodeId <node_id>
    offerAnswerTimer <10-300>

 % show global signaling sipSigControls
 
% delete global signaling sipSigControls

Command Parameters

Global SIP Signaling Control Parameters

Parameter

Length/Range

Description


egressRemoveEnudmi

NA

Controls whether the SBC removes the enumdi (ENUM dip indicator) parameter from the egress Request-URI that the SBC inserts when the PSX does an ENUM query. The options are:

  • disabled (default) - The SBC includes the enumdi parameter in the egress Request-URI when the PSX does an ENUM query.
  • enabled - The SBC does not include the enumdi parameter in the egress Request-URI even if the PSX does an ENUM query.


egressRNParam

N/A

Enable this flag to send a Redirecting Number Information Element (RNIE) in the egress leg of the call per RFC3398 when the R-URI and the To header differ.

  • disabled
  • enabled (default)

loopDetectionFeature

N/A

When enabled, the SIP Stack performs loop detection on incoming INVITE messages.

  • disabled – The SIP signaling group processes the INVITE message.
  • enabled (default)

maxPduSizeValue

N/A

The maximum PDU size recognized by the SBC:

  • pdusize2kb – 2,048 bytes
  • pdusize3kb – 3,072 bytes
  • pdusize6kb – 6,000 bytes
  • pdusize15kb (default) – 15,000 bytes
  • pdusize32kb – 32,000 bytes
  • pdusize60kb – 60,000 bytes

multipleContactsPerAor

N/A

Use this flag to support multiple contacts per Address Of Record (AoR).

  • disabled – Only a single contact per Address of Record is supported.
  • enabled (default) – The SBC maintains different RCBs for each new registration and verifies the source IP address and port during Registration Control Block (RCB) lookup.

The SBC supports validating the source IP address and the port even if multipleContactsPerAor flag is disabled. The SBC also supports locating the RCB using the AoR to perform additional validation on the source IP address and port if the parameter requireRegistration is set to "required" or "required-non-priority". This is applicable for both calls and OOD requests that are originated from the IAD.

In case of refresh registration that is originated from a different IP/port, the SBC forwards the request to the registrar and move the sate to "UPDATING". Any calls or OOD requests that are originated from the IAD while the RCB is in updating state must be validated using the previously authenticated IP/port.

When the flag multipleContactsPerAor is enabled, the SBC maintains different RCBs for each new registration. A registration is considered new when the source IP/port of the REGISTER request is different from earlier registration for the same AoR. Any of the registered UEs may initiate a communication on behalf of the AoR, and the SBC fetches the corresponding RCB based on source IP port of the UE.

Note: Refer to Multiple Contacts per AoR feature page for additional details.

Note: Even though the default value of multipleContactsPerAor is "enabled", during an upgrade the value can be either "enabled" or "disabled".


registrarSupportContactParam

N/A

Enable flag to support parameters in the Contact header:

  • disabled – Parameters in the Contact header are not supported. This value is provided only for backwards compatibility.
  • enabled (default) – Parameters in the Contact header are supported.

send503DuringSwitchoverN/A

Use this flag to control the sending of 503 message during a switchover.

  • disabled – The request is dropped with no 503 messages sent for Invites.
  • enabled (default) – Send 503 message during a switchover.

Note: The Retry-after tag is set to 60 seconds once the 503 message is sent.


sendDeRegisterContactAsStar N/A

Enable this flag to allow the SBC to send the Contact header as a star (*) in DEREGISTER messages if multipleContactsPerAor is disabled.

  • disabled
  • enabled (default)

sendSurrogateUnRegAfterRebootN/A

Enable flag to trigger de-register messages to all AORs configured to use the Surrogate Registration feature after a reboot.

  • disabled (default)
  • enabled

suppressErrorInfoHdr

N/A

Enable flag to suppress Error-Info header in a response to a request message with syntax error.

  • disabled (default) – The SBC includes Error-info header in the response.
  • enabled –  The SBC does not include Error-Info header in an error status. 

surrogateRegisterPacingTime0-10000

Use this parameter to specify the time gap, in milliseconds, between a final response of surrogate register and the next surrogate register message sent across all peers. (default = 0, disabled)

If surrogate registration is active and you wish to disable pacing, first disable surrogate registration for each peer using following command syntax:


% set addressContext <AC name> zone <zone name> ipPeer <peer name> surrogateRegistration state disabled


Note: Fully research the feature to understand pacing semantics before using it. This setting is not required in generic deployments. Pacing is applied to all surrogate REGISTER requests generated for all surrogate AoRs.


ucidNodeId

1-32767

UCID Node Id used to generate the UCID in the User-to-User Header. (default = 0)


offerAnswerTimer10 - 300 seconds

Specify the number of seconds for the SBC to wait for the Offer-Answer handshake to complete before timing out.    

Once configured, the SBC uses this value for all subsequent calls.

For backward compatibility, set the offerAnswerTimer to its default value for SIP signaling gateway.

Default: 20 seconds

Note:

The offerAnswerTimer goes beyond transaction timeout value only for Re-INVITE  transactions. For Media Resource Function timer (MRF) calls, if the offerAnswerTimer value has a value more than MRF timer value,  which is currently hard coded to 72 seconds , the call disconnects on MRF timer timeout, irrespective of the offerAnswerTimer timer value.


Command Example

To display the global configuration of all SIP signaling control parameters:

% show global signaling sipSigControls
    loopDetectionFeature         enabled;
    registrarSupportContactParam enabled;
    suppressErrorInfoHdr         enabled;
    maxPduSizeValue              pdusize3kb;
    egressRNParam                enabled;
    multipleContactsPerAor       enabled;
    surrogateRegisterPacingTime  enabled;
    ucidNodeId                   13;
    offerAnswerTimer             28
     }

Single Radio Voice Call Continuity (SRVCC)

SRVCC provides the ability to transition a voice call from the VoIP/IMS packet domain (LTE) to the legacy circuit domain. Variations of SRVCC are being standardized to support both GSM/UMTS and CDMA 1x circuit domains. For an operator with a legacy cellular network who wishes to deploy IMS/VoIP-based voice services in conjunction with the rollout of an LTE network, SRVCC offers VoIP subscribers with coverage over a much larger area than would typically be available during the roll-out of a new network.

Command Syntax

% set global signaling srvcc
    atcfUri (1-63 chars)
    callLingerTimer (1-32 seconds)
    eStnSr (1-32 chars)
	pstopsSti (0-32 chars)
    stnSr (1-32 chars)


Command Parameters

Global SRVCC Parameters

Parameter

Length/Range

Description

atcfUri1-63 charactersThe SIP URI to be used as the ATCF Path and Management URI.
callLingerTimer1-32 secondsNumber of seconds to wait for INVITE due to STN_SR before clearing the call (default=32).
eStnSr0-32 characters

The Request URI for a emergency transfer call sent by MSC on PS to CS call hand-off.

Acceptable characters: alphabetical (upper- and lower-case), numerical (0-9) and any of the following special characters: +,-,.,(,)

pstopsSti

0-32 characters

The Request URI for a Packet-Switched-to-Packet-Switched (PS-to-PS) optimized hand-over call.

Acceptable characters: alphabetical (upper- and lower-case), numerical (0-9) and any of the following special characters: +,-,.,(,)

stnSr

0-32 characters

The Request URI for a transfer call sent by MSC on PS to CS call hand-off.

Acceptable characters: alphabetical (upper- and lower-case), numerical (0-9) and any of the following special characters: +,-,.,(,)

Command Example

set global signaling srvcc pstopsSti +1-pstopsSti-222
commit

show global signaling srvcc pstopsSti
pstopsSti +1-pstopsSti-222;

Teams Support

The SBC supports special behavior of SIP Signaling, when interfacing with Microsoft Teams.

Command Syntax

% set global signaling teamsSupport <disabled | enabled>

Command Parameters


Teams Support

ParameterDescription
teamsSupport

Enable this flag to configure SIP Signaling for interfacing with MS Teams.

Note: When you enable this global control, the SBC sends out both SDES and DTLS in the offer, if both are enabled in the Packet Service Profile. This might only be required if there is a Microsoft Teams client running in a browser.

  • disabled (default)
  • enabled

Command Example

  • To configure sipIpPeerStats, use the following example:

    % set global signaling teamsSupport enabled
% commit
  • To display the teamsSupport, use the following example:

    • In the "configure" mode:

      % show global signaling teamsSupport
teamsSupport enabled;

    • In the "display" mode (when you exit the "configure" mode):

      > show table global signaling
teamsSupport    enabled;
maxNumTransfers 30;
sipPeerOverloadControl {
    samplingPeriod  2;
    discardPeriod   2;
    stepDownGain    100;
    rejectThreshold 1;
}
sipSigControls {
    registrarSupportContactParam enabled;
    maxPduSizeValue              pdusize15kb;
}