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4.2.11 Customized multimedia information services
As specified in TS 122 182 [16] and TS 22.183 [17].
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4.3 Mobility
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4.3.1 Mobility in TISPAN NGN
As specified in TS 122 101 [11]. In addition services should be able to be reconfigured so as to be suitable for the target network and target device. The service shall be reconfigured at the time the user first accesses the service from a new location. 4.3.2 Voice call continuity The requirements for voice call continuity in TS 122 101 [11] clause 21 applies for TISPAN NGN networks. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 14
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4.4 Numbering, naming and addressing
As specified in TS 123 228 [19] and TS 123 003 [20].
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4.5 Terminal requirements
The present document does not specify terminal requirements. However, NGN terminals (not precluding network adaptors) that comply with the IMS UNI interface offered by the network shall be supported by the NGN. Terminal developers guidelines are provided in annex B.
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4.6 Regulatory service requirements
As specified in TS 122 228 [6] and TS 122 101 [11]. NOTE: Additional regulatory requirements should be taken into account in further revisions of the present document.
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4.6.1 Lawful Intercept
The capabilities to support Lawful Intercept shall be as described in TS 187 005 [i.2].
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4.6.2 Emergency service
As specified in TS 122 228 [6].
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4.6.3 Identifying malicious communications
As specified in TS 122 228 [6].
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4.6.4 Anonymous communications rejection
As specified in TS 122 228 [6].
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4.7 Access network requirements
Any access to the NGN core shall provide IP connectivity, i.e. allow transport of IP packets between end user equipment and the NGN core. Solutions for access to the NGN core shall support the assignment of IP addresses to the end user equipment by the access network. These addresses may not be routable in the public Internet. Solutions for access to the NGN core shall not require changes to existing access technology infrastructure. All solutions for access to the NGN core shall support the presence of NAT and firewalls in the access network environment. Impacts on access networks shall be minimized. An NGN deployment shall not inhibit user access to the Internet and other IP networks through existing mechanisms, e.g. ISP offering of internet access to DSL users.
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4.8 Customer networks
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4.8.1 General
Access from a customer network to the NGN core shall provide IP connectivity, i.e. allow for transport of IP packets from the end user equipment. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 15 Solutions for access from a customer network to the NGN shall be able to cope with the assignment of IP addresses to the end user equipment by the customer network. These addresses may not be routable in the public Internet. Solutions for access from a customer network to the NGN shall not require technological changes to existing customer network technologies. Solutions for access from a customer network to the NGN shall have minimal impact on existing customer network deployments. The diagnostic operations on the Customer Network by an operator shall be performed in accordance with rules protecting the user's privacy.
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4.8.2 Home and small office networks
Solutions for access from a Home and Small Office network to the NGN shall be able to cope with NAT and firewalls in the home/small office environment. Solutions for access from a Home and Small Office network to the NGN shall support the following configurations: • Direct connectivity and interaction between the individual terminals and the NGN. • Indirect connectivity and interaction between the individual terminals and the NGN (e.g. via IP PBXs).
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4.8.3 Corporate networks
Solutions for access from a corporate network to the NGN shall be able to cope with NAT and firewalls in the corporate environment. Solutions for access from a Corporate network to the NGN shall support the following configurations: • Direct connectivity and interaction between the individual terminals and the NGN (e.g. to support Ipcentrex configurations). • Indirect connectivity and interaction between the individual terminals and the NGN (e.g. via IP PBXs). A mechanism shall be available in the network to provide information, if the PSTN/ISDN resources are not available.
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4.9 Interworking
As specified in TS 122 228 [6].
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4.10 Quality of Service (QoS)
The NGN shall support the following: • A wide range of QoS-enabled services. • Dynamic negotiation of QoS parameters between service and access providers based on an SLA. • Terminals that are not capable to indicate QoS requirements as part of the service request. Terminals that are capable shall also be supported. • End to end QoS provisioning. • The provisioning of QoS for application traffic where upstream and downstream flows have specific QoS requirements. • An architecture for bandwidth reservation. • QoS mechanisms to allow efficient use of access resource. • Other specific QoS requirements as contained in TS 181 018 [12]. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 16
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4.11 Security requirements
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4.11.1 General
As specified in TS 122 101 [11] except as follows: • The Access Network shall provide access connectivity to a user entitled to use the resources of the Access Network. • The NGN shall support independent verification by IMS and Access Network of the previous two requirements.
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4.11.2 NGN security
Detailed Security Requirements shall be as contained in TS 187 001 [5].
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4.11.3 Network domain security
The detailed requirements for network domain security are contained in TS 187 001 [5].
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4.12 Charging and accounting
As specified in TS 122 115 [14].
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4.13 Roles within an NGN
To provide services to the users, different roles could be identified within an NGN both at the service layer and at the transport layer. Figure 1 represents all the roles identified. Customer Environment Transport Layer Service Layer NGN Core Network Provider NGN Access Network Provider NGN Connectivity Provider NGN Service Provider Application Provider Figure 1 At the service layer 2 different roles may be identified: the NGN Service Provider and the Application Provider. The NGN service Provider provides services directly to the Customers, the Application Provider can provide more complex value added applications to the Customers, using capabilities of the NGN Service Provider. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 17 At the transport layer 3 different roles may be identified: NGN Access Network Provider, NGN Connectivity Provider and NGN Core Network Provider. Each role owns both Functional Control elements (e.g. parts of RACS or NASS) and transfer functions (e.g. AN, IP edge, xBGF, etc.). It is not within the scope of the present document specify the architectural elements belonging to the different roles. In addition to have a complete picture, a Customer environment shall be identified. These roles are technical roles: different roles can be played at the same time by a single Telecom Operator defining in such a way a variety of business roles.
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5 PSTN/ISDN emulation service
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5.1 Business models
The business model envisaged for PSTN/ISDN Emulation Service is the replacement (in whole or part) of an existing PSTN/ISDN network based on TDM with an Emulation based on IP technology. An alternative business model is the provision of PSTN/ISDN service over connections derived from broadband service, which compete with the existing or Emulated PSTN. Both business models may co-exist in the same market place. A NGN service provider shall be capable of connecting to other service provider via: • an interconnect model where bi-lateral Service Level Agreements (SLA) are established between two service providers; • an interconnect model where intermediate network(s) can provide interconnect on behalf of multiple service providers (and may be based on a single Service Level Agreement (SLA) between the SP and their intermediate service provider). A single NGN service provider shall be able to choose to support either of the interconnect models, or both of the interconnect models simultaneously.
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5.2 Service requirements
The NGN shall support PSTN /ISDN emulation that provides the user with an identical experience to that of the existing PSTN/ISDN. The NGN shall support the ability for a service operator to emulate one or more of their PSTN/ISDN services. The NGN shall support service capability definitions inherited from existing PSTN/ISDN specification. The service descriptions of the existing services for any particular network are outside the scope of the present document. It is an objective that the user shall be unaware of a change from legacy PSTN/ISDN to PSTN/ISDN emulation for those services that are emulated. For each emulated service, the service capability definitions are inherited from existing PSTN/ISDN specifications. Specific service requirements related to PSTN/ISDN Emulation are described in the following clauses. An automatic re-routing (cranckback) mechanism for handling of the communications blocked due to unavailability of PSTN/ISDN resources shall be provided by the network.
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5.3 Mobility
There is no requirement to support mobility or a nomadic capability for PSTN/ISDN Emulation. There are no additional mobility requirements. This does not prevent the existence of user nomadism where it is implicit in the chosen business model nor does it require that nomadism be actively prevented. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 18
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5.4 Numbering, naming and addressing
The users of PSTN/ISDN Emulation will be allocated numbers (or number ranges) in the appropriate E.164 number space allocated by the national numbering authority. The nature of this E.164 number will vary from operator to operator and from country to country. The design shall permit the use of both geographical and non-geographical E.164 numbers. There is no requirement to support the use of non-E.164 names within PSTN/ISDN Emulation but the use of non-E.164 names is not precluded. PSTN/ISDN emulation places no new requirements to support number portability.
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5.5 Terminal requirements
The NGN shall support terminals that use existing PSTN/ISDN interfaces. Whilst the NGN has no role in standardizing terminals it is recognized that a key aspect of the PSTN/ISDN emulation subsystem is the ability to enable PSTN/ISDN replacement whilst maintaining all the existing services in the network. NOTE: More advanced terminals may use the PSTN/ISDN emulation subsystem to provide identical PSTN/ISDN services to the user. Such advanced terminals may or may not be able to access additional services not related to PSTN/ISDN emulation but the functions of such terminals are not subject to standardization within the Release 1 of NGN.
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5.6 Regulatory service requirements
NOTE: Additional regulatory requirements should be taken into account in further revisions of the present document.
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5.6.1 Lawful Intercept service requirements
All implementations of PSTN/ISDN Emulation shall provide the ability to provide Lawful Interception (LI) in accordance with national requirements. Where possible the packet interception handover interfaces should be made available to authorities to avoid the ability of targets to maintain covert channels not monitored by TDM handover interfaces. Packet handover is most important for derived service where the packet stream is not under direct control of the provider of the Electronic Communication Network (ECN). The capabilities to support Lawful Intercept for Emulation shall be as described in TS 187 005 [i.2].
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5.6.2 Emergency service requirements
The capabilities to support the Emergency Service shall be as described in TS 102 424 [3].
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5.6.3 Malicious Communication Identity service requirements (MCID)
MCID is a service which is expected to be provided in the context of the European Telecoms Privacy Directive or equivalent regulations in other jurisdictions. The service is required for all speech calls irrespective of which network originated the call. It is normally provided following a request from the customer concerned and may be subject to authorization. The served user may be provided with the capability of explicitly declare a call as malicious.
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5.6.4 Anonymous Communications Rejection service requirements (ACR)
The service capability definition for this service is inherited from existing PSTN/ISDN specifications and no new requirements are identified. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 19
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5.7 Access networks
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5.7.1 Wireline access
The deployment of an NGN supporting PSTN/ISDN emulation may support existing access methods and access network technologies. The PSTN/ISDN User-Network Interface shall not be affected.
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5.8 Customer networks
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5.8.1 Home and small office networks
In the case of PSTN/ISDN Emulation used to replace an existing analogue or TDM network these are handled in the same way as the network which is being replaced or substituted. Where the business model involves derived voice the customer will present lines to either an Access Gateway or a Residential Gateway as appropriate. In some cases there will be a terminal that offers service in an alternative manner but that is not within the scope of the present document. A Residential Gateway may be situated within a Customer Access Gateway or on the customer network side of it. The Customer Access Gateway may use any suitable access technology. In addition where existing Primary Rate ISDN or equivalent services are provided the PSTN/ISDN Emulation may support them. The actual signalling systems and methods of presentation supported are a national matter, supported by the list of designated standards published by the European Commission.
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5.8.2 Corporate networks
Within the context of the PSTN/ISDN Emulation Corporate Networks may continue to be supported. The actual signalling systems and methods of presentation supported are a national matter supported by the list of designated standards published by the European Commission. This support may extend to the provision of VPN services using signalling systems and methods of presentation which are provided on a national basis and those that rely on European Standards.
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5.9 Interworking
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5.9.1 Interworking with legacy PSTN/ISDN
PSTN/ISDN emulation shall provide interfaces to PSTN/ISDN networks. The NGN shall support the ability for the interconnection between two PSTN/ISDN and/or emulation networks to remain unchanged from the legacy case. PSTN/ISDN Emulation shall provide a high level of interoperability with the services in the PSTN/ISDN being emulated. The degree to which service interoperability is provided is a matter for operators of Public Electronic Communications Networks and, in some cases, national regulators. A mechanism shall be available in the network to provide information, if the PSTN/ISDN resources are not available.
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5.9.2 Interworking with PSTN/ISDN emulation
PSTN/ISDN Emulation shall provide a high level of interoperability with the services in other Emulated PSTN/ISDN networks. The degree to which service interoperability is provided is a matter for operators of Public Electronic Communications Networks and, in some cases, national regulators. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 20
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5.9.3 Interworking with PLMN
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5.9.3.1 Interworking with IMS based PLMN
Interworking with the part of a PLMN that is based on an IMS shall be as described for interworking with a NGN IMS network.
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5.9.3.2 Interworking with PLMN - CS Domain
Interworking with the circuit switched part of a PLMN shall be as described above for Interworking with a PSTN/ISDN network.
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5.9.4 Interworking with packet cable network
Interworking with the Packet Cable network shall be as described for Interworking with a legacy PSTN/ISDN network or as described for Interworking with an emulated PSTN/ISDN network. The choice of method is at the discretion of the operators concerned or as directed by a regulatory authority.
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5.9.5 Interworking with NGN IMS network
As specified in TS 122 228 [6].
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5.9.6 Interworking with other networks
Interworking with non-IMS and non-TDM network is the same as for interworking with: i) a TDM based PSTN/ISDN as described above; or ii) another PSTN/ISDN Emulation as described above. The choice of method is at the discretion of the operators concerned or as directed by a regulatory authority.
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5.10 Quality of Service (QoS)
The PSTN/ISDN Emulation shall provide QoS transmission facilities to enable the same end-to-end performance requirements of the PSTN to be met. This includes any reservation of bit rate through the Access transport and also includes any transcoding facilities that may be needed.
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5.11 Security requirements
A PSTN/ISDN Emulation shall meet the security requirements placed on a national PSTN/ISDN network. Where appropriate, requirements and mechanisms may vary to take account of the underlying NGN and IP technology.
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5.12 Charging and accounting
The requirements and mechanisms for charging are a national matter.
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6 Codecs services
The following requirements apply to audio and video codecs support within the network. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 21
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6.1 General
It is the responsibility of entities at the rim of the NGN (e.g. NGN-TE) and Network equipment originating and terminating the NGN IP media flows, to negotiate and select a common codec for each "end-to-end" media session. Therefore the NGN shall allow end-to-end negotiation of any codec between NGN entities (terminal, network elements).
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6.2 Audio codec
In order to enable interworking between the NGN and other networks (including the PSTN, mobile networks and other NGNs) the NGN must be capable of receiving and presenting G.711 [23] coded speech when interconnected with another network. When a packetization size is not selected by codec negotiation between terminals and/or network elements or agreed by bilateral arrangement, a speech packetization size of 10 ms samples should be used for G.711 [23] coded speech; this is recommended as an optimum value balancing end-to-end delay with network utilization. It is recognized that there may be network constraints which require that a higher value is agreed by bilateral arrangement; in such cases a value of 20 ms is recommended. NOTE: Where a packetization size is selected by codec negotiation between terminals and/or network elements the present document places no requirements on the value to be selected. The above does not put any requirement about the codecs to be supported by terminals nor does it mandate that NGN networks shall support audio transcoding between any arbitrary codec to G.711 [23]. In addition, support for the following audio codecs is recommended: • AMR: in order to support 3GPP terminals and to facilitate the interwork with 3GPP network. • G.729A [24]: in order to facilitate the interwork with existing VoIP networks and support existing VoIP terminals. • EVRC/EVRC-B: in order to support 3GPP2 terminals and to facilitate interworking with 3GPP2 networks. 6.3 Wideband codecs
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6.3.1 General
Clause 6.1 shall take precedence over this clause, to reduce transcoding and improve both wideband interoperability and end to end quality. Wideband audio is an optional capability that may be supported by: • entities at the rim of the NGN (e.g. NGN-TE) which have a wideband audio ability; • network equipment originating and terminating the NGN IP media flows with wideband audio content. Terminals providing wideband audio capabilities shall also have NB capability and comply with clause 6.2. Network equipment providing wideband audio capabilities shall also have NB capability and comply with clause 6.2. Audio transcoding may be performed to provide end-to-end service interoperability, but should be avoided wherever possible.
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6.3.2 Wideband codecs in terminals for wideband telephony services
Terminals supporting wideband telephony services originating and terminating end to end IP media flows in NGN, shall support and offer the following wideband codecs • G.722 [7] as by default codec to be supported by any Fixed Terminal for wideband telephony services. • AMR-WB/G.722.2 [27] to interoperate with 3GPP wideband user equipment and/or user equipment with mobility according to 3GPP access for wideband telephony services. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 22 In addition, terminals supporting wideband telephony services originating and terminating end to end IP media flows in NGN should support one or more of the following wideband codecs: • G.729.1 [9]. NOTE 1: Used in some DECT NG user equipment, some VoIP and/or legacy user equipment. • EVRC-WB [10]. NOTE 2: Required for 3GPP2 user equipment and/or user equipment with mobility according to 3GPP2 access. Terminals may provide any other codecs in addition to the above list. In an exceptional case, terminals providing one or more wideband codecs none of which are in the above list (e.g. existing/legacy terminals) should be permitted in NGN. Such terminals may experience limited wideband audio interoperability.
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6.3.3 Wideband codecs in networks
Network equipment originating and terminating end to end NGN IP media flows, supporting wideband audio should provide the following wideband codecs: • G.722 [7]. NOTE 1: To support DECT NG user equipment, some VoIP and/ or legacy user equipment and/or interworking to other networks. • AMR-WB/G.722.2 [27]. NOTE 2: To support 3GPP user equipment, user equipment with mobility according to 3GPP access and/or interworking to 3GPP networks. • G.729.1 [9]. NOTE 3: Where required to support DECT NG user equipment, VoIP and/or legacy user equipment and/or interworking to some VoIP and legacy networks. • EVRC-WB [10]. NOTE 4: Where required to support 3GPP2 user equipment, user equipment with mobility according to 3GPP2 access and/or interworking to 3GPP2 networks.
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6.4 Video codec
In order to enable the interworking for video communication services between an NGN Network and other Networks the support of the H.263 profile 0 [25] and H.264 baseline profile [26] codecs is recommended. The above does not put any requirement about the codecs to be supported by terminals nor does it mandate that NGN networks shall support video transcoding between any arbitrary codec and H.263 [25] or H.264 [26].
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7 Network attachment requirements
The user network profile contains user access authentication data and information related to the required network access configuration. The NGN shall support the re-configuration of services available to the user when the user is nomadic and accesses their services from a location other than the subscribed-to location. Services may be dependent on any or all of: the user device, the access network and arrangements (e.g. roaming agreements) between the Application provider and the access network provider. The access network shall allocate resources in accordance to the services to be provided. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 23 In access roaming scenarios, those access networks that provide access to NGN services shall be able to authenticate/authorize access to the network based on information retrieved from the access networks where the user is subscribed to. To guarantee the interoperability of roaming services, the NGN access network attachment procedures shall support access network authentication based on a standardized method for identifying users at access network level (e.g. the NAI mechanism specified in RFC 4282 [i.3]). NAI based user authentication shall be supported. NASS shall support the capability to receive indications from control, transport or application subsystems that are interested to register to certain NASS events. The notification related to such an event will then be conditionally propagated to the subsystems that have registered. Backwards compatibility must be kept, meaning that this capability is not applicable to IMS and PES.
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8 CPE configuration
The NGN shall be able to provide configuration parameters and obtain operational status of the CPE. This includes the ability to provide SW upgrade, service configuration, collect operational status.
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9 Network management
Network Management requirements shall be as described in TS 188 003 [4].
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10 Control of processing overload
The NGN shall have mechanisms available to control overload that: 1) automatically maximize effective throughput (i.e. admitted service requests/sec) at an overloaded resource; 2) achieve this throughout the duration of an overload event, and irrespective of the overloaded resource's capacity or of the number of sources of overload; 3) are configurable by the service provider so that, under processing overload, a high proportion of response times at overloaded resources are low enough so as not to cause customers to prematurely abandon service requests; 4) should be possible to be applied within a service provider's NGN, and between different service providers' NGNs; 5) should be possible to be applied within an NGN subsystem (e.g. IMS, PSTN/ISDN emulation) and between different NGN subsystems. NOTE: As a general rule, an NGN's call, session and command processing resources can experience prolonged processing overload under the appropriate circumstances (e.g. partial, or full, server failure, high rates of incoming service requests). Consequently, it needs to be equipped with some form of overload detection and control (including expansive controls such as load balancing and resource replication), in order to keep response times just low enough under such processing overload to preclude customers abandoning their service requests prematurely. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 24
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11 IP addressing
The Operator of an NGN infrastructure may base the implementation on IPv4 only, IPv6 only or both. The choice is an operator option. NOTE 1: It should be recognized that a mixture of IPv4 and IPv6 within a single operator domain can cause problems for service delivery. NGN operators may support customer equipment using IPv4 only, IPv6 only or both at an IP-based User-Network Interface. The choice is an operator option. NOTE 2: It is assumed that IPv6 based customer equipment can also support IPv4 at the User-Network Interface.
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12 NGN interconnection
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12.1 General
The interconnection of Next Generation Networks may be grouped in: • Service-oriented Interconnection (SoIx). The physical and logical linking of NGN domains that allows carriers and service providers to offer services over NGN (i.e. IMS and PES) platforms with control, signalling (i.e. session-based), which provides defined levels of interoperability. This does apply for carrier-grade voice and/or multimedia services over IP interconnection. The level of interoperability depends e.g. on services, Quality of Service, security. • Connectivity-oriented Interconnection (CoIx). The physical and logical linking of carriers and service providers based on simple IP connectivity irrespective of the levels of interoperability. For example, an IP interconnection of this type is not aware of the specific end-to-end service and, as a consequence, service-specific network performance, QoS and security requirements are not necessarily assured. This definition does not exclude that some services may provide a defined level of interoperability. However, only SoIx fully satisfies NGN interoperability requirements. NGN shall support CoIx interconnections. NGN shall support SoIx interconnections. NOTE: IPTV interconnections are not covered by SoIx and CoIx. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 25 Figure 2 Figure 2 describes the SoIx and CoIx interconnection and NGN strata involved. The CoIx interconnection includes only the transport stratum and is independent of any service stratum functionalities. The SoIx interconnection includes both service and transport strata, deployment scenarios include both direct and indirect interconnection for the media path between the two NGNs. IMS interconnection aspects are covered by 3GPP. 12.2 Requirements for SoIx interconnection The following requirements for SoIx interconnections shall be addressed: Signalling: • Support of service identification. • Support of service interoperability. Codec: • Codec support and codec usage as specified in clause 6 of the present document. Routing: • Support of routing based on service. Security: • Support of Lawful interception (LI). • Support of appropriate privacy. • Support of authorization. • Support of authentication and access control. • Support of communications and data security (including integrity and confidentiality). • Support of DoS protection. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 26 Charging and accounting: • Support of CDR generation. • Support of detailed service accounting reporting. Resource, QoS and SLA: • Support of required resource allocation. • Support of admission control. • Support of address and port translation functionalities. • Support of policy control. • Support of load balancing. • Support of availability and reliability. • Support of QoS reporting.
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12.3 SoIx interconnection between NGN platforms
The interconnection link between two Carriers/Service Providers shall be "aware" of specific NGN services. It may be a physical or a logical link which carries both data and signalling bearers. The Point of Interconnection shall be a standardized interface. The Resource Control shall control the resources on the interconnection link in order to deal with different services data and signalling bearer characteristics. Over-provisioned resources on the interconnection link may be inefficient in terms of total interconnection link bandwidth usage. Security and accounting features shall be taken in account. In case of Transit scenario, the operators and/or service providers shall guarantee the end-to-end interoperability of services over the SoIx Interconnection in a standardized way.
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12.4 SoIx interconnection between NGN and other IP platforms
The interconnection link shall be "aware" of specific NGN service carriers (dimensioned to carry both data and signalling bearer). The interconnection link between the two Carriers/SPs shall be defined similar to the previous scenario. The service interoperability and the service interworking shall be ensured in a standardized way. Over-provisioned resources between the two Carrier/SP domains may satisfy some QoS and Service Level Agreements (SLA) requirements. NOTE: Over-provisioning will not guarantee any improvements on the base of traffic growth, even if the resource allocation control will be implemented on both platforms. In the case of Transit scenario the Carriers/SPs can guarantee the service end-to-end interoperability. Interworking shall take in account both signalling, security and/or accounting features. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 27
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13 IPTV
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13.1 General
This clause contains the references to the IPTV requirements specifications.
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13.2 Service-related requirements
The requirements are contained in TS 181 016 [21].
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13.3 Network capabilities
The requirements are contained in TS 181 014 [22].
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14 Transport stratum
Void.
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15 Prevention of Unsolicited Communication (PUC)
Unsolicited Communication (UC) denotes bulk communication in the NGN where the benefit is weighted in favour of the sender. In general the receiver(s) of UC do not wish to receive such communication. Some well-known examples of UC are "SPAM over Internet Telephony - SPIT" or "SPAM over Instant Messages - SPIM", however, any kind of communication service can be exploited for unsolicited communication. Following objectives and requirements were extracted from TR 187 009 [i.4]. NOTE 1: For more information, refer to TS 187 015 [i.5]. NOTE 2: The specification of PUC for Common IMS is defined in 3GPP.
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15.1 Objectives for PUC
• The NGN shall provide the ability to identify UC. • The NGN shall provide the ability to mark UC. • The NGN shall provide the ability to react to UC.
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15.2 User to NGN requirements for PUC
• The NGN shall provide a means for NGN-users to report calls as UC. • Reports of UC made by NGN-users shall be auditable by the NGN.
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15.3 NGN to User requirements for PUC
• The NGN should provide the ability for an affected user to request the rating of an UC call. • The NGN should provide the ability for an affected user to challenge the ratings made by the UC detection system. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 28
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15.4 NGN architectural requirements for PUC
• The NGN should provide at the appropriate entities in the network interfaces to extract the required information, compute the UC rating and propagate this information back on the signalling path. • The NGN should provide the possibility to block (where allowed), reroute or answer the call on behalf of the user according to a UC rating. • The NGN should provide the ability to the affected CSP to extract from the call signalling sufficient information to provide a UC rating for the call. • The NGN should provide a mechanism to convey the UC rating in the call signalling. • The NGN should provide a mechanism to allow variation in the call handling for calls with particular UC ratings. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 29 Annex A (informative): Basic communication cases for IMS networks As specified in TS 122 228 [6]. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 30 Annex B (informative): Guidance for terminal implementation As specified in TS 122 228 [6] and TS 122 101 [11] and in addition the following: • Software upgrades may be required e.g. for security purposes, as well as minor HW upgrades, e.g. chip card reader. • Solutions for access to the NGN core shall support existing terminals (e.g. personal computers). The client software should be deployable making use of download techniques but should not impact the current operating system. ETSI ETSI TS 181 005 V3.3.1 (2009-12) 31 Annex C (informative): Bibliography • IETF RFC 3966: "The tel URI for Telephone Numbers". • IETF RFC 3261: "SIP: Session Initiation Protocol". • ETSI TS 181 002: "Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); Multimedia Telephony with PSTN/ISDN simulation services". • ETSI TS 181 001: "Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); Videotelephony over NGN; Stage 1 service description". • ETSI ETS 300 059: "Integrated Services Digital Network (ISDN); Subaddressing (SUB) supplementary service; Service Description". • ETSI ETS 300 284: "Integrated Services Digital Network (ISDN); User-to-User Signalling (UUS) supplementary service; Service description". • ETSI TR 181 015: "Telecommunications and Internet Converged Services and Protocols for Advanced Networking (TISPAN); Requirements for Customized Originating and Terminating Multimedia Information Presentation (COMIP/CTMIP) and Customized Originating and Terminating Multimedia Information Filtering (COMIF/CTMIF) Requirements Analysis". ETSI ETSI TS 181 005 V3.3.1 (2009-12) 32 Annex D (informative): Change history Change history Date WG Doc. CR Rev CAT Title / Comment Current Version New Version 26-09-08 18bTD181r1 001 D Change of version number 2.4.1 3.0.0 13-11-08 CR001 TB approved 3.0.0 3.1.0 28-11-08 19bTD024r2 002 A Common IMS references 3.1.0 3.1.1 28-11-08 19bTD26r1 003 A IMS interconnection 3.1.0 3.1.1 23-01-09 19tTD051r1 004 A Corrections and editorial modifications 3.1.1 3.1.2 23-01-09 19tTD502r1 005 B Reference to IPTV specifications 3.1.1 3.1.2 23-01-09 19tTD059r1 006 B QoS requirements revision 3.1.1 3.1.2 23-01-09 19tTD070r1 007 A Common IMS reference for Annexes A and B 3.1.1 3.1.2 23-01-09 19tTD053r2 008 B Service requirements for PUC 3.1.1 3.1.2 25-02-09 20WTD202r1 009 F Correcting references for PUC work 3.1.2 3.1.3 25-02-09 20WTD283r1 010 D Regulatory requirements 3.1.2 3.1.3 CRs 002 to 010 approved at TISPAN#21 3.1.3 3.2.0 20-08-09 21bTD025r1 011 D Editorial review 3.2.0 3.2.1 20-08-09 21bTD026r1 012 A Revision of definition that contain normative text 3.2.0 3.2.1 20-08-09 21bTD027r1 013 A Revision of notes that contain normative text 3.2.0 3.2.1 30-09-09 22WTD158r1 014 B Proposed update to TS 181 005 section 6.3 based on conclusions from TR 185 013 3.2.1 3.2.2 CRs 011 to 014 TB approved at TISPAN#22 3.2.2 3.3.1 Publication 3.2.2 3.3.1 ETSI ETSI TS 181 005 V3.3.1 (2009-12) 33 History Document history V1.1.1 March 2006 Publication V2.4.1 November 2007 Publication V1.2.1 December 2009 Publication V2.5.1 December 2009 Publication V3.3.1 December 2009 Publication
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1 Scope
The present document defines the requirements for multimedia telephony services which may be supported by a TISPAN NGN. These requirements form the basis for the definition of network capabilities. An important aspect of the Multimedia Telephony with PSTN/ISDN Simulation service is to provide PSTN/ISDN like services. Nevertheless the requirements are independent of the media that is used during the communication. The present document covers part of the transition from PSTN/ISDN to an NGN. Interconnection between the existing networks and a TISPAN NGN is also covered. The present document only provides requirements for services using IMS. Services provided by a TISPAN NGN to support legacy terminals and interfaces (PSTN/ISDN emulation) are defined in existing PSTN/ISDN documents. Requirements for PSTN/ISDN Emulation are out of the scope of the present document and are described in other documents. New NGN services are out of the scope of the present document and are described in other documents. The applicability of PSTN/ISDN simulation services to services other than Multimedia Telephony (e.g. instant messaging) is not defined. Some PSTN/ISDN simulation services (for example communication waiting) are clearly not applicable to some real-time communication services. The requirements in the present document are described from the user point of view to assist in the transition of phone services to IP multimedia services with a similar behaviour. The requirements do not take into account capabilities of existing protocols. The evolution or modifications to these protocols are beyond the scope of the present document.
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2 References
References are either specific (identified by date of publication and/or edition number or version number) or non-specific. • For a specific reference, subsequent revisions do not apply. • Non-specific reference may be made only to a complete document or a part thereof and only in the following cases: - if it is accepted that it will be possible to use all future changes of the referenced document for the purposes of the referring document; - for informative references. Referenced documents which are not found to be publicly available in the expected location might be found at http://docbox.etsi.org/Reference. For online referenced documents, information sufficient to identify and locate the source shall be provided. Preferably, the primary source of the referenced document should be cited, in order to ensure traceability. Furthermore, the reference should, as far as possible, remain valid for the expected life of the document. The reference shall include the method of access to the referenced document and the full network address, with the same punctuation and use of upper case and lower case letters. NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee their long term validity.
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2.1 Normative references
The following referenced documents are indispensable for the application of the present document. For dated references, only the edition cited applies. For non-specific references, the latest edition of the referenced document (including any amendments) applies. [1] ETSI TS 181 005: "Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); Services and Capabilities Requirements". ETSI ETSI TS 181 002 V2.2.5 (2007-11) 9 [2] ITU-T Recommendation I.210: "Principles of telecommunication services supported by an ISDN and the means to describe them". [3] ETSI TS 102 424: "Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); Requirements of the NGN network to support Emergency Communication from Citizen to Authority".
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2.2 Informative references
[4] ETSI TR 180 000: "Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); NGN Terminology". [5] ITU-T Recommendation I.112 (1993): "Integrated services digital network ISDN; Vocabulary of terms for ISDNs)". [6] ITU-T Recommendation Q.9: "Vocabulary of switching and signalling terms". [7] IETF RFC 2806: "URLs for Telephone Calls". [8] IETF RFC 2396: "Uniform Resource Identifiers (URI): Generic Syntax". [9] ITU-T Recommendation E.164: "The international public telecommunication numbering plan". [10] ETSI ETS 300 095 (edition 1): "Integrated Services Digital Network (ISDN);Connected Line Identification Restriction (COLR) supplementary service; Service description". [11] ETSI EN 301 798 (V1.1.1): "Services and Protocols for Advanced Networks (SPAN); Anonymous Call Rejection (ACR) Supplementary Service; Service description". [12] ETSI ETS 300 200: "Integrated Services Digital Network (ISDN); Call Forwarding Unconditional (CFU) supplementary service; Service description". [13] ETSI EN 300 199 (V1.2.1): "Integrated Services Digital Network (ISDN); Call Forwarding Busy (CFB) supplementary service; Service description". [14] ETSI EN 300 201 (V1.2.1): "Integrated Services Digital Network (ISDN); Call Forwarding No Reply (CFNR) supplementary service; Service description". [15] ETSI ETS 300 202: "Integrated Services Digital Network (ISDN); Call Deflection (CD) supplementary service; Service description". [16] ETSI ETS 300 056: "Integrated Services Digital Network (ISDN); Call Waiting (CW) supplementary service; Service description". [17] ETSI ETS 300 139: "Integrated Services Digital Network (ISDN); Call Hold (HOLD) supplementary service; Service description". [18] ETSI EN 301 082 (V2.1.1): "Integrated Services Digital Network (ISDN); Outgoing Call Barring-Fixed (OCB-F) supplementary service; Service description". [19] ETSI EN 301 084 (V2.1.1): "Integrated Services Digital Network (ISDN); Outgoing Call Barring-User Controlled (OCB-UC) supplementary service; Service description". [20] ETSI TS 122 228 (V6.7.0): "Digital cellular telecommunications system (Phase 2+);Universal Mobile Telecommunications System (UMTS);Service requirements for the Internet Protocol (IP) multimedia core network subsystem (IMS);Stage 1 (3GPP TS 22.228 Release 6)". [21] ETSI EN 300 357 (V1.2.1): "Integrated Services Digital Network (ISDN); Completion of Calls to Busy Subscriber (CCBS) supplementary service; Service description". [22] ETSI EN 300 650 (V1.2.1): "Integrated Services Digital Network (ISDN); Message Waiting Indication (MWI) supplementary service; Service description". [23] ETSI ETS 300 183: "Integrated Services Digital Network (ISDN); Conference call, add-on (CONF) supplementary service; Service description". ETSI ETSI TS 181 002 V2.2.5 (2007-11) 10 [24] ETSI ETS 300 164: "Integrated Services Digital Network (ISDN); Meet-Me Conference (MMC) supplementary service; Service description". [25] ETSI ETS 300 178: "Integrated Services Digital Network (ISDN); Advice of Charge: charging information at call set-up time (AOC-S) supplementary service; Service description". [26] ETSI ETS 300 179: "Integrated Services Digital Network (ISDN); Advice of Charge: charging information during the call (AOC-D) supplementary service; Service description". [27] ETSI ETS 300 180: "Integrated Services Digital Network (ISDN); Advice of Charge: charging information at the end of the call (AOC-E) supplementary service; Service description". [28] ETSI ETS 300 367: "Integrated Services Digital Network (ISDN);Explicit Call Transfer (ECT) supplementary service; Service description". [29] ITU-T Recommendation I.256.3 (1992): "Integrated Services Digital Network (ISDN); general structure and service capabilities; Reverse Charging". [30] ETSI ETS 300 136 (1992): "Integrated Services Digital Network (ISDN); Closed User Group (CUG) supplementary service; Service description". [31] ETSI ETS 300 186 (Edition 1): "Integrated Services Digital Network (ISDN);Three-Party (3PTY) supplementary service; Service description".
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3 Definitions and abbreviations
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3.1 Definitions
For the purposes of the present document, the following terms and definitions given in TR 180 000 [4] and the following apply: call: See ITU-T Recommendation Q.9 [6], definition 2201. call establishment; connection establishment: See ITU-T Recommendation Q.9 [6] , definition 2207. callback: See TS 102 424 [3]. connection: See ITU-T Recommendation Q.9 [6] , definition 0011. NOTE: In the present document, the term is taken to include a bearer and its associated control signalling. communication: transfer of information between two or more users, entities, processes or nodes according to some agreed conventions NOTE: See ITU-T Recommendation I.112 [5] modified. emergency call: See TS 102 424 [3]. identity information: includes all the information (e.g. RFC 2806 [7]/RFC 2396 [8]/E.164 [9]) identifying a user, including asserted public identities (network generated) and/or unasserted (user generated) public identities incoming (communication): communication incoming to the user side of the interface interface: See ITU-T Recommendation Q.9 [6] , definition 4001. IP multimedia application: See TR 180 000 [4]. originating party: See TR 180 000 [4]. outgoing (communication): communication outgoing from the user side of the interface PSAP: See TS 102 424 [3]. PSTN/ISDN Emulation: See TR 180 000 [4]. ETSI ETSI TS 181 002 V2.2.5 (2007-11) 11 PSTN/ISDN Simulation: See TR 180 000 [4]. terminating party: See TR 180 000 [4].
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3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply: 3PTY Three Party ACR Anonymous Communication Rejection AOC-D Advice Of Charge - During the communication AOC-E Advice Of Charge - at the End of the communication AOC-S Advice Of Charge - charging information at communication Set-up time CB Communication session Barring CCBS Completion of Communication sessions to Busy Subscriber CD Communication Deflection CDIV Communication DIVersion CDIVN CDIV Notification CFB Communication Forwarding Busy CFNL Communication Forwarding on Not Logged-in CFNR Communication Forwarding No Reply CFNRc Communication Forwarding on Subscriber Not Reachable CFU Communication Forwarding Unconditional COLP COnnected Line identification Presentation COLR COnnected Line identification Restriction CONF CONFerence CS Circuit Switched CUG Closed User Group CW Communication Waiting ECT Explicit Communication Transfer HOLD Communication HOLD ICB Incoming Communications Barring IMS IP Multimedia Subsystem IP Internet Protocol ISDN Integrated Services Digital Network MCID Malicious Communication IDentification MWI Message Waiting Indication NGN Next Generation Network OCB Outgoing Communications Barring OIP Originating Identification Presentation OIR Originating Identification Restriction PLMN Public Land Mobile Network PSAP Public Safety Answer Point PSTN Public Switch Telephone Network TIP Terminating Identification Presentation TIR Terminating Identification Restriction
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4 Service Description
From the human user point of view, Multimedia Telephony with PSTN/ISDN simulation services, provides a suite of service that are, in most aspects, the same as those already existing in the PSTN/ISDN. The services described are not limited to voice media as in PSTN/ISDN, but generally applicable regardless of the media used (voice, video, etc.). In addition to the capabilities to establish a bi-directional point-to-point communication between two parties, a selected number of PSTN/ISDN Simulation services, corresponding to perceived popular PSTN/ISDN supplementary services are included in the present document. PSTN/ISDN simulation services are described from a user's perspective and are similar or almost identical to the corresponding supplementary service in PSTN/ISDN. ETSI ETSI TS 181 002 V2.2.5 (2007-11) 12 However, from a functionality distribution perspective, the present document places no particular requirements on the functionality distribution between network and terminals. Further, it is perceived that the need to preserve the split of functionality provided for supplementary services in an ISDN or PSTN is not a requirement in an NGN.
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5 Service requirements
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5.1 Mandatory requirements
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5.1.1 General
Communication sessions in an NGN may provide the ability for users to invoke multimedia telephony applications to send and receive multimedia (including voice and data) communications. The requirements, in the context of the present document, refers to the Multimedia Telephony with PSTN/ISDN Simulation Services as a complete set. If the complete set is not offered, then for reasons of compatibility, the mandatory services shall be provided as part of any multimedia telephony with PSTN/ISDN simulation service offering. There is no mandatory requirement to offer Multimedia Telephony with PSTN/ISDN Simulation Services in a particular network deployment. The multimedia telephony services shall support interworking with existing fixed and mobile voice and IP data networks, including PSTN, ISDN, Mobile and Internet. Multimedia telephony communications between NGN IMS users and users in PSTN/PLMN-CS networks shall be supported. When a multimedia telephony session originates or terminates in a circuit-switched network (telephony call), the CS telephony network user should not detect a difference from that of a communication between two CS telephony network users in terms of aspects such as the delay to set-up communications and the total permissible delay in transporting speech between the end users. The multimedia telephony with PSTN/ISDN Simulation service does not necessarily have to support all services offered by the CS telephony network. Services not interoperated across the different network types shall be declined in a graceful and consistent manner.
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5.1.2 Logged-in
The term "Logged-in" corresponds to an identity registered in the network as being able to receive and initiate communications. A user is considered "not-logged in" when the identity is not currently registered in the network. Registration and authentication procedures shall be provided as described in TS 181 005 [1].
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5.1.3 IP multimedia application subscription
There is no requirement to support standardized subscription mechanisms for multimedia telephony and PSTN/ISDN simulation applications. Multimedia telephony and PSTN/ISDN Simulation applications may require to be provisioned and configured by users and operators. There are no requirements on the network capabilities to support provisioning and configuration for specific IP multimedia applications. NOTE: The standardized service capabilities, personalized Internet web pages and evolving IP mechanisms may be used to allow user (self) provisioning, configuration and enabling of IP multimedia applications.
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5.1.4 Capability negotiation
Capability negotiation is part of a basic multimedia communications service and shall be provided as described in TS 181 005 [1] (clause 5.2.5). ETSI ETSI TS 181 002 V2.2.5 (2007-11) 13
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5.1.5 Invoking PSTN/ISDN Simulation services
The user shall be able to invoke one or more PSTN/ISDN simulation services as part of session establishment, and during an established session.
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5.1.5.1 Identification of entities
The requirements for identification of entities shall be provided as described in TS 181 005 [1].
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5.1.5.2 Emergency communications
Emergency communications requirements shall be provided as described in TS 181 005 [1].
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5.1.6 Handling of an incoming session (by the terminating party)
The specific requirements for the multimedia telephony with PSTN/ISDN simulation service shall be provided as described in clause 5.2.1.1 of TS 181 005 [1].
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5.1.7 Handling of an ongoing session
The specific requirements for the Multimedia Telephony with PSTN/ISDN simulation service shall be provided as described in clause 5.2.1.2 of TS 181 005 [1].
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5.1.8 Outgoing communications
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5.1.8.1 Anonymous communication session
A session is considered anonymous when a user receiving an incoming session cannot identify the originating party. Anonymous communication sessions shall be handled as described in TS 181 005 [1].
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5.1.9 Incoming communications
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5.1.9.1 Busy state
The requirements for busy state are provided in TS 181 005, clause 4.2.2.6 [1].