In this section:
The Proxy CSCF (P-CSCF) is the first contact point within the IM CN subsystem for subscribers in an IMS network. A P-CSCF is allocated to the IMS terminal during IMS registration and does not change for the duration of the registration. From a standards perspective, the P-CSCF behaves like a SIP Proxy, i.e. it accepts requests and services them internally or forwards them on. The P-CSCF also behaves as a User Agent in some cases, i.e. in certain conditions it may terminate and/or independently generate SIP transactions. Examples of these cases are when the P-CSCF requests the registrar for a user’s registration state updates, when performing P-CSCF initiated dialog-release etc.
Ribbon recommends using the Transparency Profile to configure transparency on the SBC Core for new deployments, as well as applying additional transparency configurations to existing deployments. Do not use IP Signaling Profile flags in these scenarios because the flags will be retired in upcoming releases.
Refer to the SBC SIP Transparency Implementation Guide for additional information.
Figure 1: SBC Deployed as P-CSCF
At a high level, the functions performed by the P-CSCF are:
In IMS networks, the P-CSCF interfaces with the following other functional elements:
SBC Core products using the P-CSCF role support "b=AS" (application-specific bandwidth) to calculate audio bandwidth.
Figure 2: UE Registration Call Flow
A brief description of the call-flow is as follows:
A brief description of the call-flow is as follows:
The following profiles are configured:
set profiles services transparencyProfile TRANS_PROF_ACCESS sipHeader To set profiles services transparencyProfile TRANS_PROF_ACCESS sipHeader From set profiles services transparencyProfile TRANS_PROF_ACCESS sipHeader Path set profiles services transparencyProfile TRANS_PROF_ACCESS sipHeader Accept set profiles services transparencyProfile TRANS_PROF_ACCESS sipHeader Reason set profiles services transparencyProfile TRANS_PROF_ACCESS sipHeader Server set profiles services transparencyProfile TRANS_PROF_ACCESS sipHeader Warning set profiles services transparencyProfile TRANS_PROF_ACCESS sipHeader Call-Info set profiles services transparencyProfile TRANS_PROF_ACCESS sipHeader Alert-Info set profiles services transparencyProfile TRANS_PROF_ACCESS sipHeader Error-Info set profiles services transparencyProfile TRANS_PROF_ACCESS sipHeader User-Agent set profiles services transparencyProfile TRANS_PROF_ACCESS sipHeader Referred-By excludedMethods register,subscribe,info,publish,message,options,update,bye set profiles services transparencyProfile TRANS_PROF_ACCESS sipHeader Request-URI set profiles services transparencyProfile TRANS_PROF_ACCESS sipHeader Accept-Language set profiles services transparencyProfile TRANS_PROF_ACCESS sipHeader Contact set profiles services transparencyProfile TRANS_PROF_ACCESS sipHeader P-Called-Party-Id commit set profiles services transparencyProfile TRANS_PROF_ACCESS sipMessageBody application/pidf+xml set profiles services transparencyProfile TRANS_PROF_ACCESS sipMessageBody application/rlmi+xml set profiles services transparencyProfile TRANS_PROF_ACCESS sipMessageBody message/external-body set profiles services transparencyProfile TRANS_PROF_ACCESS sipMessageBody application/pidf+xml set profiles services transparencyProfile TRANS_PROF_ACCESS sipMessageBody application/cpim-pidf+xml set profiles services transparencyProfile TRANS_PROF_ACCESS sipMessageBody application/pidf-diff+xml set profiles services transparencyProfile TRANS_PROF_ACCESS sipMessageBody application/dialog-info+xml set profiles services transparencyProfile TRANS_PROF_ACCESS sipMessageBody application/simple-filter+xml set profiles services transparencyProfile TRANS_PROF_ACCESS sipMessageBody application/resource-lists+xml set profiles services transparencyProfile TRANS_PROF_ACCESS sipMessageBody application/conference-info+xml set profiles services transparencyProfile TRANS_PROF_ACCESS sipMessageBody application/simple-message-summary set profiles services transparencyProfile TRANS_PROF_ACCESS sipMessageBody application/vnd.3gpp.srvcc-ext ignoreTransparency yes commit set profiles services transparencyProfile TRANS_PROF_ACCESS state enabled commit set addressContext ADDR_CONTEXT1 zone ZONE1 sipTrunkGroup TG_TOWARDS_UE services transparencyProfile TRANS_PROF_ACCESS commit
set addressContext ADDR_CONTEXT1 ipInterfaceGroup LIG1 ipInterface LIF1 ceName SBX portName pkt0 ipAddress 10.4.8.16 prefix 24 altIpAddress fd00:10:6b50:248f::a altPrefix 60 set addressContext ADDR_CONTEXT1 ipInterfaceGroup LIG1 ipInterface LIF1 mode inService state enabled set addressContext ADDR_CONTEXT1 ipInterfaceGroup LIG2 ipInterface LIF2 ceName SBX portName pkt2 ipAddress 10.4.9.16 prefix 24 altIpAddress fd00:10:6b50:249f::a altPrefix 60 set addressContext ADDR_CONTEXT1 ipInterfaceGroup LIG2 ipInterface LIF2 mode inService state enabled set addressContext ADDR_CONTEXT1 ipInterfaceGroup LIG3 ipInterface LIF3 ceName SBX portName pkt0 ipAddress 10.4.8.18 prefix 24 altIpAddress fd00:10:6b50:248f::c altPrefix 60 set addressContext ADDR_CONTEXT1 ipInterfaceGroup LIG3 ipInterface LIF3 mode inService state enabled set addressContext ADDR_CONTEXT1 ipInterfaceGroup LIG4 ipInterface LIF4 ceName SBX portName pkt0 ipAddress 10.4.8.18 prefix 24 altIpAddress fd00:10:6b50:248f::c altPrefix 60 set addressContext ADDR_CONTEXT1 ipInterfaceGroup LIG4 ipInterface LIF4 mode inService state enabled set addressContext ADDR_CONTEXT1 staticRoute 10.0.0.0 8 10.4.8.1 LIG1 LIF1 preference 100
set profiles services emergencyCallProfile IMS-EMG prefix 911 commit
set profiles services sipSecurityProfile PCSCF sipSecurityMechanism ipsec-3gpp precedence 1 commit
set addressContext ADDR_CONTEXT1 zone ZONE1 sipTrunkGroup TG_PCSCF_INT_IP policy signaling ipSignalingProfile DFL_PCSCF_UE_TG_PROF commit set addressContext ADDR_CONTEXT1 zone ZONE1 sipTrunkGroup TG_PCSCF_INT_IP signaling P-HeaderExtensions insertpVisitedNetworkID 'exampleNetworks' commit set addressContext ADDR_CONTEXT1 zone ZONE1 sipTrunkGroup TG_PCSCF_INT_IP signaling registration requireRegistration required-nonpriority commit set addressContext ADDR_CONTEXT1 zone ZONE1 sipTrunkGroup TG_PCSCF_INT_IP signaling prefRequireTransparency enabled commit set addressContext ADDR_CONTEXT1 zone ZONE1 sipTrunkGroup TG_PCSCF_INT_IP signaling condIncMethInAllowHdr enabled commit
set addressContext ADDR_CONTEXT1 zone ZONE1 sipTrunkGroup TG_PCSCF_INT_IP signaling keepSupport enabled outboundSupport enabled commit set addressContext ADDR_CONTEXT1 zone ZONE1 sipTrunkGroup TG_PCSCF_INT_IP services natTraversal outboundTcpKeepaliveTimer 240 outboundUdpKeepaliveTimer 60 commit
set addressContext ADDR_CONTEXT1 diamNode DIAMNODE originRealm sbc.com primaryOriginHost primary.sbc.com secondaryOriginHost secondary.sbc.com transactionTimeout 6000 ipInterfaceGroupName LIF1 ipV4Address 172.16.13.120 set addressContext ADDR_CONTEXT1 diamNode DIAMNODE state enabled commit set addressContext ADDR_CONTEXT1 diamNode DIAMNODE peer RX.EXAMPLE.COM fqdn htpcgw01.ims.mnc094.mcc235.3gppnetwork.org ipAddress 172.16.13.30 commit set addressContext ADDR_CONTEXT1 diamNode DIAMNODE peer RX.EXAMPLE.COM state enabled commit set addressContext ADDR_CONTEXT1 diamNode DIAMNODE realmRoute RX.EXAMPLE.COM realm ims.mnc094.mcc235.3gppnetwork.org peer RX.EXAMPLE.COM appId rx commit set addressContext ADDR_CONTEXT1 diamNode DIAMNODE realmRoute RX.EXAMPLE.COM state enabled commit set addressContext ADDR_CONTEXT1 zone ZONE1 sipTrunkGroup TG_PCSCF_INT_IP media pcrf pcrfRealm ims.mnc094.mcc235.3gppnetwork.org pcrfCommitment supported cushionPacketSize enabled cushionNullSdp enabled
set addressContext ADDR_CONTEXT1 diamNode DIAMNODE originRealm sbc.com primaryOriginHost example.sbc.com secondaryOriginHost example.sbc2.com transactionTimeout 6000 ipInterfaceGroupName LIF1 ipV4Address 172.16.13.120 set addressContext ADDR_CONTEXT1 diamNode DIAMNODE state enabled commit set addressContext ADDR_CONTEXT1 diamNode DIAMNODE peer RF.EXAMPLE.COM fqdn htpcgw01.ims.mnc094.mcc235.3gppnetwork.org ipAddress 172.16.13.30 commit set addressContext ADDR_CONTEXT1 diamNode DIAMNODE peer RF.EXAMPLE.COM state enabled commit set addressContext ADDR_CONTEXT1 diamNode DIAMNODE realmRoute RF.EXAMPLE.COM realm ims.mnc094.mcc235.3gppnetwork.org peer RF.EXAMPLE.COM appId rf commit set addressContext ADDR_CONTEXT1 diamNode DIAMNODE realmRoute RF.EXAMPLE.COM state enabled commit set global signaling diamSigControls defaultCCF 172.16.13.30 commit set global signaling diamSigControls enableRfApp enabled commit set global signaling diamSigControls generateFailedEventAcr enabled commit set global signaling diamSigControls maxACRretransmission 3
set addressContext ADDR_CONTEXT1 zone ZONE1 sipTrunkGroup TG_PCSCF_INT_IP services emergencyCallHandlingMode none emergencyCallProfile IMS-EMG commit set addressContext ADDR_CONTEXT1 zone ZONE1 sipTrunkGroup TG_PCSCF_INT_IP signaling usePsxRouteForEmergencyCall enable commit
set addressContext ADDR_CONTEXT1 zone ZONE1 sipTrunkGroup TG_PCSCF_INT_IP services sipSecurityProfile PCSCF commit
set addressContext ADDR_CONTEXT1 zone ZONE1 id 5 sipSigPort 1 ipInterfaceGroupName LIG1 ipAddressV4 10.4.8.16 ipAddressV6 fd00:10:6b50:248f::a portNumber 5060 transportProtocolsAllowed sip-tcp,sip-udp,sip-tls-tcp,sip-sctp mode inService state enabled set addressContext ADDR_CONTEXT1 zone ZONE1 dialogTransparency enabled set addressContext ADDR_CONTEXT1 zone ZONE1 disableZoneLevelLoopDetection disabled
The following flags must be configured:
The following parameters are configured :
The following must be enabled in PSX under "IP SIGNALING PROFILE":
The following "Relay Flags" must be enabled under "Ip Signaling profile":
The following parameters are to enabled :
The following parameter is to be enabled:
set addressContext ADDRESS_CONTEXT1 zone ZONE1 sipTrunkGroup TG_TOWARDS_UE commit
The following profiles/fields must be enabled:
The following profiles are configured:
set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader To set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader From set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader Path set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader Accept set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader Reason set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader Server set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader Warning set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader Call-Info set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader Alert-Info set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader Error-Info set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader User-Agent set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader Referred-By excludedMethods register,subscribe,info,publish,message,options,update,bye set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader Request-URI set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader Accept-Language set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader P-Called-Party-Id set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader Require set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader Proxy-Require set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader Security-Client set profiles services transparencyProfile TRANS_PROF_CORENW sipHeader Security-Verify commit set profiles services transparencyProfile TRANS_PROF_CORENW sipMessageBody application/pidf+xml excludedMethods register,invite,subscribe,info,publish,message,options,update,bye set profiles services transparencyProfile TRANS_PROF_CORENW sipMessageBody application/pidf+xml set profiles services transparencyProfile TRANS_PROF_CORENW sipMessageBody application/rlmi+xml set profiles services transparencyProfile TRANS_PROF_CORENW sipMessageBody message/external-body set profiles services transparencyProfile TRANS_PROF_CORENW sipMessageBody application/pidf+xml set profiles services transparencyProfile TRANS_PROF_CORENW sipMessageBody application/cpim-pidf+xml set profiles services transparencyProfile TRANS_PROF_CORENW sipMessageBody application/pidf-diff+xml set profiles services transparencyProfile TRANS_PROF_CORENW sipMessageBody application/dialog-info+xml set profiles services transparencyProfile TRANS_PROF_CORENW sipMessageBody application/simple-filter+xml set profiles services transparencyProfile TRANS_PROF_CORENW sipMessageBody application/resource-lists+xml set profiles services transparencyProfile TRANS_PROF_CORENW sipMessageBody application/conference-info+xml set profiles services transparencyProfile TRANS_PROF_CORENW sipMessageBody application/simple-message-summary commit set profiles services transparencyProfile TRANS_PROF_CORENW state enabled commit set addressContext ADDR_CONTEXT1 zone ZONE2 sipTrunkGroup TG_TOWARDS_SCSCF services transparencyProfile TRANS_PROF_CORENW commit
set addressContext ADDR_CONTEXT1 zone ZONE2 dialogTransparency enabled set addressContext ADDR_CONTEXT1 zone ZONE2 disableZoneLevelLoopDetection disabled
The following flags must be configured:
The following parameters must be configured under "Ip Signaling Profile".
The following must be enabled in PSX under "IP SIGNALING PROFILE":
The following "Relay Flags" must be enabled under "Ip Signaling profile":
The following parameters are to enabled :
Select P-Preferred-ID from Privacy Information options (in Privacy option)
Select None from SIP TO Header Mapping (under SIP Headers And Parameters option)
The following profiles/fields must be enabled:
Select Services as Not Screened.
Figure 14: SIP Trunk Group for SCCAS
Refer Configuring SBC Towards S-CSCF/SCCAS section in Configuring SBC as IBCF.
set addressContext ADDR_CONTEXT1 zone ZONE3 id 5 sipSigPort 1 ipInterfaceGroupName LIG3 ipAddressV4 10.4.8.18 ipAddressV6 fd00:10:6b50:248f::c portNumber 5060 transportProtocolsAllowed sip-tcp,sip-udp,sip-tls-tcp,sip-sctp mode inService state enabled set addressContext ADDR_CONTEXT1 zone ZONE3 dialogTransparency enabled
Refer IPTG-5 (Towards Peer IBCF) section in Configuring SBC as IBCF.
set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 media mediaIpInterfaceGroupName LIG3 set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 ingressIpPrefix 10.54.80.101 32 set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 ingressIpPrefix 10.54.80.8 32 set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 mode inService state enabled set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 signaling registration requireRegistration none set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 signaling relayNonInviteRequest enabled set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 services transparencyProfile IBCF_COMMON_HTP set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 callRouting sendRouteUriToPsx enabled set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 signaling skipDTGLookupForRouteHdr enabled set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 callRouting useRouteSet received set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 media omrAllowed enabled set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 media primaryRealmName RealmName2 set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 media directMediaAllowed disabled set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 transitIoi "IBCF" set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 callRouting sendRouteUriToPsx enabled set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 services honorSdpClockRate enabled set addressContext ADDR_CONTEXT1 zone ZONE3 sipTrunkGroup IPTG-4 services preconditions transparent
For PSX related configuration, refer to the following sections of IBCF Configuration (Zone 1 Configuration (Towards P-CSCF in Roaming)):