ONIT 2009

Presence service integration using interconnected IP multimedia core networks

Transcript

1. Presence service integration using interconnected IP Multimedia Core Networks Eugen Mikóczý, Sebastian Schumann Slovak University of Technology, Bratislava Stephan Massner, Michael Maruschke Hochschule für Telekommunikation, Leipzig
2. Outline •  Infrastructure •  Interconnection •  Presence service in the IMS •  Deployment •  Current state •  Future use cases
3. Infrastructure •  Bratislava – ngnlab.eu: Virtualized environment for educational and research purposes – OpenIMS testbed installed and integrated with services (e.g. presence) •  Leipzig – NGN test and research lab with OpenIMS •  Interconnected infrastructure via secured OpenVPN channel
4. Testbed in Bratislava SIP I-CSCF P-CSCF S-CSCF Signaling core Support systems HSS NGN ASF NGN NGN NGN NGN ASF ASF ASF ASF Proxy Application layer XDMS (voice) (conf.) (IPTV) (presence) •  Logically separated HW machine •  Xen virtualization •  All components via NAT behind proxy •  Different VLANs •  VPN client on proxy connects to Leipzig GW
5. Interconnection Media Data Signalling Data Application Data AS UE AS UE GW GW IMS Testbed STU IMS Testbed HfTL Public Internet VPN Tunel Core IMS #B Core IMS #A HfTL - Hochschule f?r Telekommunikation Leipzig (Germany) Legend: GW - Gateway (for Interconnection) AS - Application Server UE - User Equipment STU - Slovak University of Technology Bratislava (Slovakia) Interconnection - Current status
6. Interconnection ctd. Legend: AS - Application Server VPN Tunel Media Data Signalling Data Application Data AS GW Core IMS Network Core Transport Steps from plain to standardized Interconnection Establishment of a shared VPN- interconnection between two different and separate located IMS-based Multimedia Networks Step 1)
7. Interconnection ctd. Legend: IBCF - Interconnection Border Control Function AS - Application Server VPN Tunel Media Data Signalling Data Application Data AS GW IBCF Core IMS Network Core Transport Steps from plain to standardized Interconnection Establishment of a standardized interconnection in the signalling layer using the IBCF to connect two IMS-based Multimedia Networks Step 2)
8. Interconnection ctd. Legend: IBCF - Interconnection Border Control Function AS - Application Server SPDF - Service-based Policy Decision Fcuntion IBGF - Interconnection Border Gateway Function VPN Tunel Media Data Signalling Data Application Data AS GW IBCF SPDF IBGF Core IMS Network Core Transport Steps from plain to standardized Interconnection Establishment of a standardized interconnection in the signalling layer using the IBCF and in the transport layer using the IBGF to connect two IMS-based Multimedia Networks Step 3)
9. Interconnection ctd. Application Data Media Data Signalling Data ANGF - Access Network Gateway Function UE - User Equipment AS - Application Server Legend: RACS - Ressource and Admission Control Subsystem IBGF - Interconnection Border Gateway Function NASS - Network Attachment Subsystem P-CSCF - Proxy Call Session Control Function IBCF - Interconnection Border Gateway Function IMS Testbed Network IP Transport IBGF RACS NASS ANGF Core IMS P- CSCF IBCF AS UE Ut Gm Ut Gm Ic Iz Network IP Transport IBGF RACS NASS ANGF Core IMS P- CSCF IBCF AS UE Slovak University of Technology Telekommunikation Leipzig Hochschule f?r IMS Testbed Future view of Interconnection possibilities Data Media Data Media
10. Presence service in the IMS •  Proxy only L3 outbound proxy for UE •  P-CSCF is logical end-point (L7) for connections •  P-CSCF assigns P-Asserted-Identity (PAI) header that presence server (PS) will trust later •  S-CSCF triggers presence related SIP message to be relayed towards PS
11. Presence service in the IMS ctd. •  Initial filter criteria (IFC) enables routing to application server, e.g. PS •  Filter: Event: presence, presence.winfo •  Both domains (.sk .de) forward to one PS •  PS trusts PAI header from both domains (otherwise also challenging possible)
12. Service Profile User Profile Service Profile Includes information about service access and dependencies to user registration state and service availibility. Each service profile can be specified for a single user or shared by different users by linking the service profile.
13. Service Profile ctd. User Profile Service Profile Indicator: registered/unregistered/independend The Indicator describe the dependency to user registration state. Three different states will be differ: - registered (user is registered) - unregistered (user is not registered) - independend (user registered or not)
14. Triggering User Profile Filter: Trigger Point + AS Information Service Profile Indicator: registered/unregistered/independend Filter describe an term including information about trigger point and application server access data belong the service profile. An trigger point is a logical expression including sip message parts and matching expressionsaccording the service.
15. Triggering ctd. User Profile available if AS isn't Proceedings SIP-URI Logical expression: CNF: ( A or B ) and C DNF: ( A and B ) or C Filter: Trigger Point + AS Information Service Profile Indicator: registered/unregistered/independend Requested URI Method header Session case SDP line matches/ equals/ is one of Service Point Trigger:
16. Deployment •  OpenIMS CSCFs and HSS from FOKUS Fraunhofer – P-CSCF can be reached via proxy externally – Other components on one VLAN •  OpenSIPS as PS, configured to work as IMS ASF – PS can be reached via S-CSCF, separate VLAN •  OpenXCAP as XDMS, integrated with PS – XDMS can be reached via proxy externally
17. Current state •  L3 secured interconnection •  ASF sharing not via standardized IMS procedures but simple direct access •  Interconnection proven to work (no significant packet delay, security verified) •  After the base is proven, future steps towards standardized interconnection can be taken
18. Future use cases •  IBCF in signaling layer to interconnect IMS core networks •  IBCF in signaling and IBGF in transport layer to interconnect the networks •  Integrate also IMS interconnected call scenarios acc. standards and perform tests
19. Thank you.