Interactions between PCRF and AF

AF Session Establishment (AF initiated)

1. The AF receives an internal or external trigger to set-up a new AF session and provides Service Information. The AF identifies the Service Information needed (e.g. IP address of the IP flow (s), port numbers to be used, information on media types, etc).

2. The AF provides the Service Information to the PCRF by sending a Diameter AAR for a new Rx Diameter session. If this AF session is associated with a sponsor, Sponsor-Identity AVP and the Application-Service-Provider-Identity AVP are included in Sponsored-Connectivity-Data AVP. If usage thresholds are to be associated with this sponsored AF session, then Granted-Service-Unit AVP is included in Sponsored-Connectivity-Data AVP.

3. The PCRF stores the received Service Information.

4. If the PCRF requires subscription related information and does not have it, the PCRF sends a request to the SPR in order to receive the information.

5. The SPR replies with the subscription related information containing the information about the allowed service(s), QoS information and PCC Rules information

6. If the AF session is associated with a sponsor, The PCRF identifies the affected established IP-CAN Session(s) using the information previously received from the PCEF and the Service Information received from the AF.

7. The PCRF sends a Diameter AAA to the AF. The PCRF indicates whether the support for UE IP address/mask in the TFT filter is available in the IP-CAN session.

8. The PCRF interacts with the PCEF for PCRF-Initiated IP-CAN Session Modification via RAR/RAA.

AF Session Establishment (AF initiated)

1. The AF receives an internal or external trigger to modify an existing AF session and provide related Service Information.

2. The AF identifies the Service Information needed (e.g. IP address of the IP flow(s), port numbers to be used, information on media types, etc.).

3. The AF provides the Service Information to the PCRF by sending a Diameter AAR for the existing Rx Diameter session corresponding to the modified AF session. If this AF session is associated with a sponsor, Sponsor-Identity AVP and Application-Service-Provider-Identity are included in Sponsored-Connectivity-Data AVP. If application usage thresholds are to be associated with this sponsored AF session, then Granted-Service-Unit AVP is included in Sponsored-Connectivity-Data AVP.

4. The PCRF stores the received Service Information.

5. The PCRF identifies the affected established IP-CAN Session(s) using the information previously received from the PCEF and the Service Information received from the AF.

6. The PCRF sends a Diameter AAA to the AF.

7. The PCRF interacts with the PCEF via RAR/RAA.

AF Session Termination (AF initiated)

1. The AF receives an internal or external trigger for a session release.

2. The AF sends a session termination request, Diameter STR, to the PCRF to request the removal of the session. The AF can request access network information within the STR by adding a Required-Access-Info AVP.

3. The PCRF identifies the affected IP-CAN Session where PCC Rules and, if available, QoS Rules for the IP flow(s) of this AF session are installed. These PCC/QoS Rules need to be removed.

If the AF did not request access network information, and if no usage thresholds due to an AF session associated with a sponsor were provided that relate to the installed PCC rules, step 4a applies. Otherwise step 4b applies.

4a. The PCRF sends Diameter STA, session termination answer, to the AF.

4b. The PCRF sends Diameter STA, session termination answer, to the AF and includes access network information obtained in steps 5,6,7.

5. The PCRF interacts with the PCEF via RAR/RAA.

PCEF Initiated IP-CAN Session Modification

1. The PCEF may receive a request for IP‑CAN Session modification. The IP-CAN session modification can be initiated upon receiving UE-initiated resource modification request, a new IP-CAN bearer establishment signalling , due to a specific event (e.g. UE requested PDN connectivity in all cases) or an internal trigger.

2. The PCEF informs the PCRF about the IP-CAN session modification for non-roaming case and Home Routed roaming scenario. The PCEF sends a CCR command to the PCRF including the CC-Request-Type AVP set to the value “UPDATE_REQUEST”. For an IP-CAN Session modification where an existing IP-CAN bearer is modified, the PCEF supplies the specific event that caused the IP-CAN Session modification within the Event-Trigger AVP and the PCC rule name(s) and their status within the Charging-Rule-Report AVP.

3-4. If the AF requested a notification of the corresponding event, the PCRF sends a Diameter RAR with the Specific-Action AVP set to indicate the event that caused the request. If the session modification affected a sponsored data flow and the PCRF detects that the usage threshold provided by the AF has been reached, this message includes the accumulated usage in the Used-Service-Unit AVP within the Sponsored-Connectivity-Data AVP and the Specific-Action AVP set to the value USAGE_REPORT.

5-6. If step 6 takes place, the AF may take the application specific procedure (e.g. for IMS refer to 3GPP TS 23.228[x], replies with a Diameter RAA and may provide updated service information within.

7-8. The PCRF selects or generates PCC Rule(s) to be installed. The PCRF may also identify existing PCC rules that need to be modified or removed. For the non-roaming case, and for the case when the UE is roaming in a Home Routed scenario, the PCRF provisions the PCC Rules to the PCEF using CCA command.

PCEF Initiated IP-CAN Termination

1. The PCEF detects that the termination of an IP-CAN Session or bearer is required.

2. The PCEF sends a CCR to the PCRF, indicating the IP-CAN Session termination. The PCEF requests the termination of the Gx session using the CC-Request-Type AVP set to the value TERMINATION_REQUEST. If the usage monitoring is enabled, the PCEF informs the PCRF about the resources that have been consumed by the user since the last report. If the Required-Access-Info AVP is included in any PCC Rule, the PCEF informs the PCRF about the access network information.

3. The PCRF identifies the AF sessions that are bound to IP flows of the removed IP-CAN Session.

4. The PCRF acknowledges the Gx session termination by sending a CCA to the PCEF.

5. The PCRF indicates the session abort to the AF by sending an ASR to the AF.

6. The AF responds by sending an ASA to the PCRF.

7. The AF sends an STR to the PCRF to indicate that the session has been terminated.

8. The PCRF responds by sending an STA to the AF. If the provided PCC rules are related to an AF session associated with a sponsor, usage thresholds were provided by the AF earlier, and the PCRF has usage data that has not yet been reported to the AF, the PCRF informs the AF about the resources that have been consumed by the user since the last report. If the AF requested the PCRF to report access network information in step 7, the PCRF informs the AF about the access network information.

Diameter Interfaces and their Specs

Interface	Network location	Supported version
Diameter Base Protocol		IETF RFC 3588, 4960, 793
Diameter Commands for 3GPP		IETF RFC 3589
Diameter Credit Control App		IETF RFC 4006
NASREQ Support for Network Access Server		IETF RFC 4005
EAP Support for Extensible Authentication Protocol		IETF RFC 4072
Mobile IPv4 Support for Diameter Mobile IPv4		IETF RFC 4004
Diameter Mobile IPv6		IETF RFC 5447
Diameter SIP Application		IETF RFC 4740
Sh interface	Between AS and HSS, Subscription and Authentication Data – IMS	3GPP TS 29.328 & TS 29.329
Sd interface	Between PCRF and TDF (Traffic Detection Function)	3GPP TS 29.212
Sy interface	Between PCRF and OCS/OFCS, Policy and Charging Control over Sy reference point	3GPP TS 29.219
Dh interface	Between AS and SLF	3GPP TS 29.328 & TS 29.329
Rf interface	Between AS and OFCS, postpaid charging	RFC 4006, 3GPP TS 32.225 & TS 32.299
Ro interface	Between AS and OCS, online charging in IMS & LTE	RFC 4006, 3GPP TS 32.225 & TS 32.299
Re interface	Between OCF and Rating function	3GPP TS 32.296
Cx interface	Between CSCF and HSS, Subscription and Authentication Data – IMS	3GPP TS 29.228 & TS29.229
Dx interface	Between CSCF and SLF	3GPP TS 29.228 & TS29.229
Sp interface	Between PCRF and SPR	3GPP TS 23.203, TS 29.328 & TS 29.329
Rx interface	Between AF and the PCRF, QoS and Policy	3GPP TS 23.203 & TS 29.214
Gx interface	Between PCEF and the PCRF, QoS and Policy	3GPP TS 29.212 & TS 23.203
Gy interface	Between OCS and PCEF, online charging	3GPP TS 32.299, TS 32.251 & RFC 4006
Gz interface	Between PCEF and OFCS	3GPP TS 32.240, TS 32.295
Gq interface	Between AF and PDF	3GPP TS 29.209
Gi interface	Between Packet Domain and an external packet data network	3GPP TS 29.061
SGi interface	Between the EPC based PLMN and the packet data network	3GPP TS 29.061
Zh interface	Between BSF and HSS	3GPP TS 29.109 & TS 33.220
Zh interface	Between BSF and HSS (used between operators)	3GPP TS 29.109 & TS 33.220
Dz interface	Between BSF and SLF	3GPP TS 29.109 & TS 33.220
Zn interface	Between BSF and NAF	3GPP TS 29.109 & TS 33.220
Zn' interface	Between BSF and Zn Proxy	3GPP TS 29.109 & TS 33.220
Dw interface	Between the 3GPP AAA Server and an SLF	3GPP TS 29.234
Wa interface	Between the WLAN AN and the 3GPP AAA Proxy	3GPP TS 29.234
Wd interface	Between the 3GPP AAA Proxy and 3GPP AAA Server	3GPP TS 29.234
Wx interface	Between the 3GPP AAA Server and the HSS	3GPP TS 29.234
Wm interface	Between the 3GPP AAA Server and the PDG	3GPP TS 29.234
Wg interface	Between the 3GPP AAA Server/Proxy and the WAG	3GPP TS 29.234
Pr interface	Between the 3GPP AAA Server and the PNA	3GPP TS 29.234
Wm interface	Between the 3GPP AAA Server and the PDG	3GPP TS 29.234
Gmb interface	Between GGSN and BM-SC	3GPP TS 29.061
Mz interface	Mz is the roaming variant of the Gmb reference point with the same functionality	3GPP TS 29.061
Bi interface	CCF to BS	3GPP TS TS 32.225
MM10 interface	Multimedia Messaging Service (MMS)	OMA MM10 interface
Ty interface	Between AGW and PCRF	3GPP2 TSG-X X.S0013-014
Tx interface	Between AF and PCRF	3GPP2 TSG-X X.S0013-013
S6a interface	Between MME and HSS, Subscription and Authentication Data	3GPP TS 29.272
S6b interface	Between the 3GPP AAA Server/Proxy and the PDN GW	3GPP TS 23402
S6d interface	Between SGSN and HSS, Subscription and Authentication Data	3GPP TS 29.272
S7c interface	Transfer of (QoS) policy information from PCRF to the S-GW.	3GPP TS 32820, TS 23402
S9 interface	Between PCRF in the HPLMN (H PCRF) and a PCRF in the VPLMN (V PCRF)	3GPP TS 23.203 & TS 29.215
S13 and S13' interface	Between EIR and MME/SGSN	3GPP TS 29.272
Gxa interface	PCRF and the BBERF	3GPP TS 23.203
Gxb interface	Between ePDG and vPCRF	3GPP TS 23.203
Gxc interface	BPCRF and the BBERF	3GPP TS 23.203
SWa interface	Between an un-trusted non-3GPP IP access and the 3GPP AAA Server/Proxy	3GPP TS 23402
SWd interface	Between the 3GPP AAA Proxy and 3GPP AAA Server	3GPP TS 23402
SWn interface	Between Untrusted Non-3GPP IP Access and ePDG	3GPP TS 23402
SWm interface	Between the 3GPP AAA Server/Proxy and the ePDG	3GPP TS 23402
SWx interface	Between the 3GPP AAA Server and the HSS	3GPP TS 23402
Sta interface	Between a trusted non-3GPP IP access and the 3GPP AAA Server/Proxy	3GPP TS 23402
H2 interface	Between the 3GPP AAA Server and the HA	3GPP TS 23402
Gq’ interface	Between AF and RACS	ETSI TS 183.017
E2 interface	Between AF and NASS	ETSI TS 283 035
E4 interface	Between NASS and RACS	ETSI TS 283 034
E5 interface	Between UAAF – UAAF	ETSI TS 282 004
Re interface	Between RCEF and RACS	ETSI TS 183 060
A3 interface	Between UAAF and AMF	ETSI TS 282 004
A4 interface	Between CLF and UAAF	ETSI TS 282 004
Rr interface	x-RACF	03196-NGN-R3
Zh interface	Generic Authentication Architecture (GAA)	PKT-SP-29.109
Zn interface	Generic Authentication Architecture (GAA)	PKT-SP-29.109
Cx interface	CSCF- HSS	PKT-SP-29.229
Dx interface	CSCF- SLF	PKT-SP-29.229
Pkt-laes-2 interface	Session Control Element — DF (electronic surveillance requirements)	PKT-SP-ES-INF-I01
P-CSCF- PAM Interface	Between P-CSCF – PAM	PKT-SP-QOS-I02-080425, 3GPP TS 23.203 & TS 29.214
Pkt-mm-2 interface	Policy Server — CMTS	3GPP TS 29.212 & TS 23.203
TC-6	Based on 3GPP Rx	MSF-IA-DIAMETER.010-FINAL
TC-7	Based on 3GPP Ty	MSF-IA-DIAMETER.014-FINAL
TC-8	Based on 3GPP Tx	MSF-IA-DIAMETER.013-FINAL
TC-9	Based on 3GPP Rq	MSF-IA-DIAMETER.005-FINAL
TC-10	Based on 3GPP Gx	MSF-IA-DIAMETER.012-FINAL
TC-11	Based on 3GPP e4	MSF-OA-DIMATER.011-FINAL
DB-0	Based on 3GPP Cx/Dx	MSF-IA-DIAMETER.006-FINAL
DB-2	Based on 3GPP Sh/Dh	MSF-IA-DIAMETER.003-FINAL
BI-1	Based on 3GPP Rf	MSF-IA-BILLING.001-FINAL
LOC-1	Based on 3GPP e2	MSF-IA.DIAMETER.008-FINAL
Rw interface	Between the Policy Decision Physical Entity (PD-PE) and the Policy Enforcement Physical Entity (PE-PE)	ITU Q.3303.3
Rs interface	Between Service Control Physical Entity (SC-PE) and Resource and Admission Control Physical Entity (RAC-PE)	ITU Q.3301

PacketCable, 3GPP, CableLabs, IMS ??!!!

PacketCable ?? -> Multimedia over Cable internet 

PacketCable is an industry consortium founded by CableLabs with the goal of defining standards for the cable television modem access industry. CableLabs leads this initiative for interoperable interface specifications in order to deliver real-time multimedia services over two-way cable networks. Built on top of the industry’s DOCSIS (Data Over Cable Service Interface Specifications) cable modem infrastructure, PacketCable networks use the Internet Protocol (IP) to enable a wide range of multimedia services, such as Voice over IP (IP telephony), multimedia conferencing, interactive gaming, and general multimedia applications.

A DOCSIS network with PacketCable extensions enables cable operators to deliver data and voice traffic efficiently using a single high-speed, quality-of-service (QoS)-enabled broadband (cable) architecture.

The PacketCable effort dates back to 1997 when cable operators identified the need for a real-time multimedia architecture to support the delivery of advanced multimedia services over the DOCSIS architecture.


PacketCable is a CableLabs specification effort designed to support the convergence of voice, video, data, and mobility technologies. There are tens of millions of cable broadband customers, and the capability of the network to provide innovative services beyond high-speed Internet access is ever-increasing. In particular, real-time communication services based on the IP protocols, such as Voice over Internet Protocol (VoIP), are rapidly evolving and consumers are embracing a wide-range of client devices and media types. It is expected that new technologies, such as Video over IP communications and the ability to display voice and video mail message notifications on a TV-set, will change the way communication and entertainment services are offered. These cutting edge technologies will present exciting new opportunities for cable operators to offer high-value services to consumers in a cost-effective manner.

PacketCable defines an architecture and a set of open interfaces that leverage emerging communications technologies, such as the IETF Session Initiation Protocol (SIP) [RFC 3261], to support the rapid introduction of new IP-based services onto the cable network. A modular approach allows operators to flexibly deploy network capabilities as required by their specific service offerings, while maintaining interoperability across a variety of devices from multiple suppliers. Intentionally non service-specific, the platform should provide the basic capabilities necessary for operators to deploy services in areas such as:

• Enhanced Residential VoIP and IP Video Communications – Capabilities such as video telephony; call treatment based on presence, device capability, identity; and 'Click to dial' type of features;

• Cross Platform Feature Integration – Capabilities such as caller's name and number identification on the TV and call treatment from the TV;

• Mobility services and Integration with Cellular and Wireless Networks – Capabilities such as call handoff and roaming between PacketCable VoIP over WiFi and wireless-cellular networks; voice-mail integration; and single E.164 number (e.g., telephone number);

• Multimedia Applications – Capabilities such as QoS-enabled audio and video streaming;

• Commercial Services Extensions – Capabilities such as PBX extension; IP Centrex Services to small to medium-sized businesses; and VoIP trunking for enterprise IP-PBXs;

• Residential SIP Telephony Extensions – Capabilities such as traditional telephony features (e.g., call waiting, caller ID), operator services, and emergency services.

3GPP IMS?? -> Multimedia Over Wireless Network (LTE)

The 3rd Generation Partnership Project (3GPP) unites [Six] telecommunications standard development organizations (ARIB, ATIS, CCSA, ETSI, TTA, TTC), known as “Organizational Partners” and provides their members with a stable environment to produce the Reports and Specifications that define 3GPP technologies.

The project covers cellular telecommunications network technologies, including radio access, the core transport network, and service capabilities - including work on codecs, security, quality of service - and thus provides complete system specifications. The specifications also provide hooks for non-radio access to the core network, and for interworking with Wi-Fi networks.
3GPP specifications and studies are contribution-driven, by member companies, in Working Groups and at the Technical Specification Group level.
The Four Technical Specification Groups (TSG) in 3GPP are;

• Radio Access Networks (RAN),
• Service & Systems Aspects (SA),
• Core Network & Terminals (CT) and
• GSM EDGE Radio Access Networks (GERAN).

CableLabs and 3GPP :

The PacketCable architecture is based on the 3GPP IMS architecture, with some incremental extensions. Extensions include use of additional or alternate functional components compared with the IMS architecture, as well as enhancements to capabilities provided by the IMS functional components. Some of the PacketCable enhancements to the IMS include:

• Support for Quality of Service (QoS) for IMS-based applications on DOCSIS access networks, leveraging thePacketCable Multimedia architecture [MM TR];

• Support for additional access signaling security and UE authentication mechanisms;

• Support for provisioning, activation, configuration, and management of UEs;

• Support for regulatory requirements such as number portability, preferred carrier, and PacketCable lawful interception.

PacketCable IMS Architecture:

 

 3GPP IMS Architecture:

PacketCable IMS call flow:

1. UE registration with S-CSCF via P-CSCF
2. UE1 calls UE2
3. P-CSCF triggers AAR to PAM and PCRF (Rx Interface )
4. PCRF installs flow in CMTS
5.  ==== RTP data flow  ====
6. End

Aim of PacketCable 2.0:

The general aim of PacketCable 2.0 is to allow cable operators to deliver all manner of IP-based applications (data, video, and voice) seamlessly across its traditional wired and forthcoming wireless infrastructures.

References :

• Google Kadavul
• CableLabs
• 3GPP