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The “Service layer” Issues for discussion. Piero Castoldi, Fabio Baroncelli, Barbara Martini. WP4 NOBEL Meeting Stockholm, Sweden September 2 -3 , 2004. Outline. NGN efforts & recommendations Framing of the “Service Layer” within the NOBEL project Our view and open problems
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The “Service layer”Issues for discussion Piero Castoldi, Fabio Baroncelli, Barbara Martini WP4 NOBEL Meeting Stockholm, Sweden September 2-3, 2004
Outline NGN efforts & recommendations Framing of the “Service Layer” within the NOBEL project Our view and open problems Some conclusions Acknowledgements: comments received on the mailing list and privately from Massimo & Andrea, Monika, Bela, Lieven, Antonio.
NGN efforts history • Study started in early 2001. As the result of coordination between ITU-T and ETSI, it was decided that ITU-T SG13 leads NGN study. • NGN discussion became more active in 2003. ITU-T SG13 set up JRG-NGN (Joint rapporteur group for NGN) to progress the work on NGN extensively. • At the meeting in June 2004, two fundamental Recommendations were consented: • Y.2001: NGN overview • Y.2011: General reference model for NGN • Other useful reference for terminology: Y.110 Source: http://www.aptsec.org/meetings/2004/WSNGN/ WS-DOC/ASTAP04-WS.NGN-08_ITU-T_Status-NTT-view.ppt
Definition of NGN in Rec. Y.2001 • A packet-based network able to provide telecommunication services and able to make use of multiple broadband, QoS-enabled transport technologies and in which service-related functions are independent from underlying transport-related technologies • It supports generalized mobility which will allow consistent and ubiquitous provision of services to users. Source: http://www.aptsec.org/meetings/2004/WSNGN/ WS-DOC/ASTAP04-WS.NGN-08_ITU-T_Status-NTT-view.ppt
Recommendation Y.2011 (1) • The service “thing” of NGN is not a plane, nor a layer, it is a “stratum” isomorphic to the well known transport stratum. • NGN service stratum provides the user functions that control and manage service resources to enable end-user services and application (as defined in D2?) that will be mapped into network services (as defined in D2?) • NGN transport stratum provides the user functions that transfer data, and functions that control and manage the transport resources to carry user data between terminating entities. • NGN management is the union of service stratum management plane and transport stratum management plane. The same applies for control plane..
Recommendation Y.2011 (2) • Which functions belong to the service stratum and which to the transport stratum has to be identified. • Interfaces and/or reference points have to be identified. • Control functions • Control of services (user authentication and identification, service admission control, etc) • Control of transport (network admission control, network resource/policy control, etc) • Management functions • Management of services (configuration of service resources to be further studied according to Y.2011) • Management of transport (TMN management functions) [M.3050, M.3400] • Transport functions [G.805 and G.807] • Technology may be different but transport functions such as adaptation and trail termination are common to the transport planes of the two strata (same modeling) • Resources • Phyisical and non-physical (logical) components used to construct services (e.g. application modules) and networks (e.g. network segments) [Y.110]
Early steps in NOBEL (1): “Service layer” in Client side Out of scope ! Access Network PPI Management Plane Management Plane UPI Access Network “Service layer” NMI-A NMI-A UNI E/I-NNI Control Plane Control Plane CCI NMI-T CCI NMI-T Transport Plane Transport Plane Network Provider Network Provider NOBEL Network
Early steps in NOBEL (2): “Service layer”in Network Provider Positioning “Service layer” “Service layer” Access Network Access Network PPI Management Plane Management Plane NMI-A NMI-A E/I-NNI Control Plane Control Plane NMI-T CCI CCI NMI-T Transport Plane Transport Plane Network Provider Network Provider NOBEL Scope
UPI Access network Access network NSI (?) UNI ? “Service Layer” = Service Stratum ? Early steps in NOBEL(3): Interfaces to/from “Service Layer” Management Plane NMI-A NMI-T Control Plane CCI Transport Plane ASTN = Transport Stratum NSI=Network to Service Interface Note: actual data channels not shown in the figure
Application Network Access Network Access Network Application Network UPI UPI NSI NSI UNI “Service Layer” ? ? “Service Layer” UNI ? ? Access Network and Service Layer Management Plane PPI Management Plane NMI-A NMI NMI-A E/I-NNI Control Plane Control Plane NMI-T NMI-T CCI CCI Transport Plane Transport Plane Network Provider Network Provider NSI=Network to Service Interface Note: actual data channels not shown in the figure
From Access Network to Application Network • A UPI/UNI (Call) Request: Access Network Network Provider • L1-L3 VPN • With following main characteristics • Bandwidth allocation (possibly dynamic) • QoS level which level of protection / restoration by which technologies • Technology-dependent at least within the layer • A NSI (Service) Request: Application Network Network Provider • A pool of video on Demand sessions, an Internet access, etc. • With following sample characteristics • DiVx quality, DVD quality per video session • Internet Gold for large SME • Technology-independent but service dependent
Is the Service Layer the NGN Service Stratum? Service Management Plane NSI-M (WP1&WP4 ?) ? (WP4) Application Network ?(WP1) Service Control Plane NSI-C (WP1 & WP4 ?) PPI Management Plane Management Plane ? (WP1) ?(WP1) ? (WP4) NMI-A NMI-A Service Transport Plane E/I-NNI Control Plane Control Plane NMI-T CCI NMI-T CCI “Service Layer”= Service Stratum= Service Provider Transport Plane Transport Plane Network Provider= Transport Stratum Network Provider= Transport Stratum NSI=Network to Service Interface Note: actual data channels not shown in the figure
Possible functions of the Service Stratum entities • Service Management Plane (SMP) • It maintains the database of SLA, current service resource usage, access authorization • In general it is responsible of commercial aspects of service provisioning: service marketing, billing, usage and contractual obligations according to SLA • Centralized similarly to the MP of the Transport Stratum • Service Control Plane (SCP) • Dynamic aspects of service provisioning such as service discovery • Actual mapping of application requests into network services requests • Distributed similarly to the CP of the Transport Stratum • Service Transport Plane (STP) • Dummy separation related to the segment of transport belonging to the Service Stratum.
New Interfaces related to “Service Stratum” • Internal interfaces (WP1?) • SMP SCP • SCP STP • SMP STP • External interfaces (WP1/WP4?) • SMP MP • SCP CP • Application Network SMP (NSI-M) • Application Network SCP (NSI-C)
Conclusions Topic is borderline between WP1 and WP4. WP4 competence may be needed because the Service Stratum (Service Provider?) has the same structure of a Network Provider (TP, CP, MP). Identified a possible set of interfaces We must restrict our attention to what can be reasonably pursued within NOBEL scope and time span of the project.