Network Working Group P. Sijben Internet Draft Lucent Technologies Document: 14 July 2000 Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON); TIPHON Release 3; Network architecture and reference configurations Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet- Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. 1. Abstract The contents of this Internet Draft is a reprint of the body of the architecture document (DTS 02003 v0.10.8) of the TIPHON project. This document describes a functional architecture for the purposes of defining a voice over IP architecture that can interwork with the existing Switched Circuit Networks (SCN). The full document is publicly available and can be found at http://docbox.etsi.org/Tech-Org/TIPHON/Document/tiphon/07- drafts/wg2/DTS02003/ the current version is 0.10.8. Later versions will appear in the same directory. This full document describes protocol independent information flows and state diagrams on all the reference points. The next step in the TIPHON process will be the mapping of the reference points as defined in this document to existing standards. Since TIPHON does not intend to duplicate work so the project would appreciate assistance from IETF experts in the mapping of its information flows to the appropriate IETF protocols. Candidate protocols for the implementation of this architecture are SIP, MEGACOp and possibly others. 2. Conventions used in this document 2.1 Definitions Sijben Expires 1 February 2001 1 TIPHON architecture 14 July 2000 For the purposes of the present document, the following terms and definitions apply: administrative a network controlled by a single operator. domain Gateway an endpoint on a network wich provides for real time, two way communication between an IP based network and an Switched Circuit Network (SCN). Information Defines a complete set of logical information flow exchanged between two functional entities. Interconnection a functional entity connecting two networks having function differing administrative policy such as Quality of Service (QoS) or addressing policy but employing the same signalling protocol, and transport technology, at the point of interconnect. Interface a common boundary between two communicating entities. One or more protocols may be implemented across an interface Interworking a function connecting two networks of different function signalling and or transport technology IP network a managed transport network supporting IP IP Telephony This phrase is used as a shorthand to describe any telephony related service that is supported on IP. NOTE: Such services may also be supported by other technologies. Protocol a set of rules and formats which govern exchange of information across an interface between two functional entities for purposes of information transfer Reference point a conceptual point at the conjunction of two non overlapping functions. service a network controlled by a Service Provider which provider offers service to other persons network Switched a telecommunications network, e.g. Public Switched Circuit Network Telephone Network (PSTN), Integrated Services (SCN) Digital Network (ISDN), and General System for Mobile communications (GSM), that uses circuit- switched technologies for the support of voice calls. The SCN may be a public network or a private network Telephone call: a two-way speech communication between two users by means of terminals connected via network infrastructure. Terminal: an endpoint other than a gateway or a multipoint control unit. TIPHON a system that complies with the mandatory compliant requirements identified in the TIPHON requirements system documents together with compliance to the parts of the TIPHON specifications in which these requirements are embodied. Ticket a ticket is obtained through the registration session, when used in a call it provides the terminal/user with a means to show a valid Sijben Expires 1 February 2001 2 TIPHON architecture 14 July 2000 registration exists. 2.2Abbreviations For the purposes of the present document, the following abbreviations apply: BC Bearer Control BICC Bearer Independent Call Control CC Call Control DTMF Dual Tone Multi Frequency FG Functional Grouping IN Intelligent Network IP Internet Protocol IPTN IP Telephony Network IWF InterWorking Function MC Media Control MSC Message Sequence Charts NFG Network Functional Grouping OGFG Originating Gateway Functional Grouping OTFG Originating Terminal Functional Grouping PCM Pulse Code Modulation PSTN Public Switched Telephony Network QoS Quality of Service SC Service Control SCN Switched Circuit Networks SCNIW Switched circuit network inter-working function F SDL Specification and Description Language SIP Session Initiation Protocol SSP Service Switching Point TGFG Terminating Gateway Functional Grouping TTFG Terminating Terminal Functional Grouping 3. Scope The present document defines the network architecture and the reference configurations that are necessary for: - the delivery of telephone calls which originate in an Internet Protocol (IP) network and are delivered to Switched Circuit Networks (SCN); - the delivery of telephone calls which originate in SCNs and are delivered in an IP network; - the delivery of telephone calls which originate in SCNs, routed through a IP network and finally delivered to an SCN; and - the delivery of telephone calls which originate and terminate in IP networks. Such calls may be routed using an SCN. These four scenarios are part of TIPHON Release 3. The architecture includes provision of information and facilities which are incidental to the delivery of telephone calls described above. The present document builds upon the concepts embodied in the TIPHON Phase II Network Architecture and Reference Configurations [5] by considering the additional scenarios and the expansion of the IP network into a more appropriate network model. Sijben Expires 1 February 2001 3 TIPHON architecture 14 July 2000 The present document is applicable to equipment performing the roles of terminal, and Gateway, and also to entities within the IP network that are necessary to support the four scenarios of TIPHON Release 3. Where the text indicates the status of a requirement (i.e. as strict command or prohibition, as authorisations leaving freedom, or as a capability or possibility), this may modify the nature of a requirement within a referenced standard used to provide the capability. 4. Introduction The network architecture and reference configurations contained in the present document are derived from examination of the capabilities required by [6] for the support of TIPHON Scenarios 0, 1, 2, 3 and 4 as identified in [4]. The present document demonstrates how the scenarios given in [4], may be expressed as a set of interconnected networks with associated Interconnecting Functions. From this model, the concepts of functional planes, Functional Groupings, and functional layers are developed. Where there is a requirement that an information flow needs to be exchanged between physical equipment, a reference point is defined. Where an information flow will only be internal to pieces of physical equipment, no reference point is defined. 5. Networks TIPHON Scenarios 1, 2, 3 and 4 require interconnection of IP Telephony Networks (IPTN) and Switched Circuit Networks (SCN). For the purpose of the model, functionality can be distributed across a number of networks. Each network is part of only one administrative domain. When different administrative domains provide all functions needed to e.g. originate a call, these functions pertain to different networks. Each administrative domain may have its own policies on addressing, Quality of Service (QoS), etc. Each network may further be decomposed into functional groups, as shown in Clause 7. 5.1 Networks involved in registration Figure 1 shows the network types that may inter-operate during the registration of a user. +---------+ +---------------+ +--------+ | | | | | | | Serving |_______| Intermediate |_______| Home | | IPTN | | IPTN | | IPTN | +---------+ +---------------+ +--------+ Figure 1. TIPHON generic network registration model. The Home IPTN is the principle place where the user information is stored. The Home IPTN provides the functions required for registration and for subscriber related operations. The Serving IPTN provides the function required to register the user and to forward the registration towards the Home IPTN. Sijben Expires 1 February 2001 4 TIPHON architecture 14 July 2000 The Intermediate IPTN provides the functions required to connect the Serving IPTN and the Home IPTN during the registration. The intermediate IPTN is only present when the Serving IPTN and the Home IPTN are not directly connected. An IPTN may act as both the Serving IPTN and the Home IPTN. Networks involved in calls Figure 2 shows the different types of networks that may inter- operate for calls in TIPHON compliant systems. A specific call may not involve all network types. Each network will include any required interconnecting and interworking functions. +--------+ | | /| Home |\ / | IPTN | \ / | | \ / +----+---+ \ / | \ / | \ / | \ / | \ +---------+ / +-------+-------+ \ +---------------+ | Serving |/______| Intermediate |_____\_| Terminating | | IPTN | | IPTN | \| IPTN | +---------+ +-------+-------+ +---------------+ \ / | \ / \ / | \ / \ / | \ / X | X +---------+ / \ +-------+-------+ / \ +---------------+ | | / \ | | / \ | | | Serving |/_____\| Intermediate |/_____\| Terminating | | SCN | | SCN | | SCN | +---------+ +---------------+ +---------------+ Figure 2: TIPHON generic network call model. The Originating IPTN contains a set of functions required for originating calls from an IP terminal device. The Originating SCN contains a set of functions required for originating calls from a SCN terminal device. The Intermediate IPTN contains a set of functions required for connecting calls between originating and terminating networks. This network may not be present for some calls but may be present several times in a call. The Intermediate SCN contains a set of functions required for connecting calls between originating and terminating networks. This network may not be present for some calls but may be present several times in a call. The Terminating IPTN contains a set of functions required for terminating calls to an IP terminal device. The Terminating SCN contains a set of functions required for terminating calls to a SCN terminal device. Sijben Expires 1 February 2001 5 TIPHON architecture 14 July 2000 The Home IPTN contains a set of functions required for subscription- related operations. An IPTN may act as any combination of an Originating IPTN, and/or a Home IPTN and/or a Terminating IPTN. 6 Functional Planes Each of the networks in the TIPHON generic network model may be considered as comprising distinct groupings of functionality. Within a network, these functions interact to enable the policies and business objectives for that network to be achieved through exercising appropriate control of the resources within that network. In order to provide a structured analysis of the requirements, the concept of 'functional planes' is used. Each functional plane contains a high level grouping of functionality. IPTNs can be considered to contain sets of similar functions and it is possible to consider these functions to be grouped as planes of common functionality. The IPTN can be separated into an IP Transport plane and an IP Telephony Application plane. Figure 3 identifies the following functional planes: -IP Telephony Application; -IP Transport; -SCN; -Management. +-------+ +-----------------------------------------+ +------+ + + + + + + + M +--+ TIPHON Application plane +--+ S + + a +--+ +--+ C + + n + + + + N + + a + +-----------------+-----------------------+ + + + g + /|\ + P + + e + | + l + + m + | + a + + e P + | + n + + n l + | + e + + t a + \|/ + + + n + +-----------------+-----------------------+ + + + e +--+ +--+ + + +--+ IP Transport Plane +--+ + + + + + + + +---|---+ +-----------------------------------------+ +---|--+ | | | | --------------------------------------------------------- Figure 3. TIPHON Functional Planes. The IP Telephony Application plane makes use of capabilities provided by the other functional planes and it contains functions to support IP telephony. The IP Transport plane contains the functionality relating to the underlying packet transport and the functionality of servers in Sijben Expires 1 February 2001 6 TIPHON architecture 14 July 2000 general use. The details of this functional plane are not considered further in the present document. The SCN plane contains the functionality relating to the SCN. The details of this functional plane are not considered further in the present document. The Management plane contains the functionality relating to network management. The details of this functional plane are not considered further in the present document. 7. Functional groupings Functionality in the IP Telephony Application plane can be gathered into functional groups. 7.1 Functional groupings involved in registration Figure 4 shows functional groupings for registration. +--------------+ +------------+ +--------------+ +------------+ | | | | | | | | | Terminal | | Serving | | Intermediate | | Home | | Registration |----| Network |----| Network |---| Network | | Functional | | Functional | | Functional | | Functional | | Grouping | | Grouping | | Grouping | | Grouping | +--------------+ +------------+ +--------------+ +------------+ Figure 4. Overview of functional groupings involved in registration. The Terminal Registration Functional Grouping represents the functionality of the registering terminal. The Serving Network Functional Grouping represents the functions required to enable the user to register and to use services. The Intermediate Functional Grouping connects the Serving Network Functional Group to the Home Network Functional Grouping. The Home Network Functional Grouping represents functionality relating to the user's profile and subscription. The Home Network Functional Grouping and the Serving Network Functional Grouping may reside in the same network or in different networks. 7.2 Functional groupings involved in a call Figure 5 shows functional groupings for a call. Sijben Expires 1 February 2001 7 TIPHON architecture 14 July 2000 +-------------+ +--------------+ +-------------+ + Originating + + + + Terminating + + Terminal + + + + Terminal + + Functional +=============+ +============+ Functional + + Grouping + + + + Grouping + +-------------+ + + +-------------+ + Network + + Functional + + Grouping + +-----+-------------+ + + +-------------+-----+ + + Originating + + + + Terminating + + + SCN + Gateway + + + + Gateway + SCN + + + Functional +=======+ +======+ Functional + + + + Grouping + + + + Grouping + + +-----+-------------+ +--------------+ +-------------+-----+ Figure 5. Overview of functional groupings involved in a call. The Originating Terminal Functional Grouping represents the functionality of the calling terminal. The Originating Gateway Functional Grouping represents the functionality of the ingress gateway from an SCN. The Terminating Terminal Functional Grouping represents the functionality of the called terminal. The Terminating Gateway Functional Grouping represents the functionality of the egress gateway to an SCN. The Network Functional Grouping represents all of the functionality of the IP network(s) in support of the call. Figure 5 shows the case where the originating and terminating functional groupings are associated with a single 'network'. Where the originating and terminating functional groupings are associated with different networks, the Network Functional Grouping can be separated into an Originating Network Functional Grouping and a Terminating Network Functional Grouping (see figure 6) +--------------------------------------------------------------------+ + + + +-------------+ +-----------------+ +-------------+ + + + Originating + + Interconnecting + + Terminating + + + + Network +=========+ Network +========+ Network + + + + Functional + + Functional + + Functional + + + + Grouping + + Grouping + + Grouping + + + +-------------+ +-----------------+ +-------------+ + + + + Network Functional Grouping + + + +--------------------------------------------------------------------+ Figure 6. Separation of Network Functional Groupings into originating and terminating Network Functional Groupings. Sijben Expires 1 February 2001 8 TIPHON architecture 14 July 2000 Figure 6 also includes Interconnecting Functional Groupings that provide functions, e.g. protocol conversions, policy enforcement, that enables the networks to communicate. NOTE 1: In some implementations, there may be no need for an interconnection function between some networks, but it is necessary to include this functionality to develop a consistent model. Where there is an intermediate network between the Originating Network Functional Grouping and the Terminating Network Functional Grouping, the Network Functional Grouping can be further subdivided to include one or more Intermediate Network Functional Groupings (see Figure 7). 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Intermediate Network Functional Grouping. As in Figure 6, Interconnecting Functional Groupings are included to enable the networks to communicate. Also, Figure 7 includes an Intermediate Gateway Functional Grouping that provides communication with SCNs NOTE 2: the figures do not consider mobility aspects. These functional groupings may be used to construct the four scenarios as follows: - for Scenario 1, the call is from an Originating Terminal Functional Grouping to a Terminating Gateway Functional Grouping ; - for Scenario 2, the call is from an Originating Gateway Functional Grouping to a Terminating Terminal Functional Grouping; - for Scenario 3, the call is from an Originating Gateway Functional Grouping to a Terminating Gateway Functional Grouping ; and - for Scenario 4, the call is from an Originating Terminal Functional Grouping to a Terminating Terminal Functional Grouping using a pair of Intermediate Gateway Functional Groupings enabling communication via an SCN. Sijben Expires 1 February 2001 9 TIPHON architecture 14 July 2000 8. Functional decomposition of the IP Telephony Application plane The architecture for the IP Telephony Application plane consists of functional entities organised into functional layers. One functional layer builds upon functionality provided by another functional layer. Together they provide the telephony application. This grouping is useful for the understanding of the functionality involved but does not imply any physical implementation. There are information flows between the functional entities. Information flows may be: - between functional entities in the same functional layer; - between a functional entity in one functional layer and a functional entity in the next functional layer upwards; and - between a functional entity in one functional layer and a functional entity in the next functional layer downwards. A functional entity may have one or more of these types of information flow. There are information flows between functional entities in the IP Telephony Application plane and the other functional planes. Where it can be determined that there is a requirement for a physical interface between entities residing in separate pieces of physical equipment, a reference point will be defined. One reference point may encompass multiple distinctive information flows. A standardised protocol will be required to support information flows in cases where a reference point is defined. 8.1 Introduction to the functional layers The TIPHON functional architecture has 5 functional layers: the service functional layer, the service control functional layer, the call control functional layer, the bearer control functional layer and the media functional layer. These functional layers are shown in Figure 8. For simplicity only two functions are shown in each functional layer with all of the possible communication paths within the functional layer and to the adjacent functional layers. Sijben Expires 1 February 2001 10 TIPHON architecture 14 July 2000 +-------+ +-------+ + + + + ------+ +------+ +------- Service + + + + +-------+ +-------+ _________________________________________________ +-------+ +-------+ + + + + ------+ +------+ +------- Service + + + + Control +-------+ +-------+ _________________________________________________ +-------+ +-------+ + + + + ------+ +------+ +------- Call + + + + Control +-------+ +-------+ _________________________________________________ +-------+ +-------+ + + + + ------+ +------+ +------- Bearer + + + + Control +-------+ +-------+ __________________________________________________ +-------+ +-------+ + + + + ------+ +------+ +------- Media + + + + Control +-------+ +-------+ Figure 8. Functional layers in the IP Telephony Application plane. In the subsequent sub-clauses each of the functional layers is introduced. 8.1.1 The Services functional layer The Services functional layer shall support a range of services (e.g. Authentication) provided internally to a service network or functional grouping, or provided by third parties either locally or remotely via other networks or functional groupings. This functional layer has the following functions. Service profile Provides information required for function registration and stores information received during registration. Provides on request information needed for call establishment. Sijben Expires 1 February 2001 11 TIPHON architecture 14 July 2000 User profile Holds information about the user function Route function Provides address/number translation, number length determination and telephony routing capabilities. 8.1.2 The Service Control functional layer The Service Control functional layer shall contain functionality that is needed for the calls but may have a life span longer or shorter than the duration of the call (examples are terminal registration, call routing). The Service Control functional layer shall provide an interface to functions in the Services functional layer that may be provided internally to a service network, or provided by third parties either locally or remotely via other networks. This functional layer has the following functions. Service Control (SC) Provides support for calls function Number portability Provides a routable user name or address to the called user. Called User location Determines where the called user currently is within the service provider network. Name to Name Converts a user name to a routable user translation name. Name to address Provides a routable address associated translation with the user name. Call access Authorises a call to proceed. authorisation Registration (terminal Registers a user at a terminal with a part) Function service provider. Registration (network Accepts registration of a user at a part) Function terminal. 8.1.3 The Call Control functional layer The Call Control functional layer shall maintain a call context. The call context allows the services offered by the Bearer Control functional layer to provide the connections and capabilities requested by the customer as permitted by the service provider. In order to achieve this control, the Call Control functional layer may request information from the Service Control functional layer. The Call Control functional layer sends and receives signalling to users and networks. This functional layer has the following functions. Sijben Expires 1 February 2001 12 TIPHON architecture 14 July 2000 Call Control (CC) Maintains the call state and, if Function present, provides services that change the call state e.g. call hold, suspend, three way and conferencing. Communication with peer Call Control functions for the establishment and release of calls. Requests services from functions in the Service Control functional layer. Request determination of, allocation of, and release of, resources from Bearer Control functions. 8.1.4 The Bearer Control functional layer The Bearer Control functional layer manages the logical association between pairs of endpoints. Bearer control shall be responsible for mapping call topology to individual media flows (e.g. connect parties a, b and c together). These flows may be between any pair of media processing functions in the media functional layer. This layer has the following functional functions: Bearer Control (BC) Allows or disallows media streaming Function based on information from call control Bearer negotiation Negotiates with other Bearer Control functions. Media resource Communicates with the Media Control acquisition function to obtain media resources for the bearer. 8.1.5 The Media Control functional layer The Media Control functional layer shall be responsible for the properties of the individual media flows. In this functional layer media encoding is determined, Quality of Service (QoS) paths are reserved and firewalls are controlled in conjunction with the IP Transport plane. This functional layer has the following functions. Media Control (MC) Provides IP transport addresses for functions media reception and transmission. Circuit Network Media Termination of for example: all lower- Termination functional layer circuit network hardware and protocols, including the method by which speech is placed on the wire, e.g. PCM a-law, PCM mu-law, etc. Sijben Expires 1 February 2001 13 TIPHON architecture 14 July 2000 Media Processing Performs signal processing functions such as voice compression, network echo-cancellation, silence suppression, comfort noise generation, encryption, codec translation, fax conversion, media insertion (DTMF, messages) filtering and analogue modem conversion (for passing analogue modem signals 'transparently' through the packet network). Media Resource Allocates internal resources in the Management media plane Packet Media Termination of all methods involved in Termination putting media over the packet network. This includes transport protocols and framing. IP transport signalling Reserves QoS paths and controls firewalls in the IP Transport plane. 8.2 Examples This subclause contains some examples describing the entities defined above and their inter-relationship. 8.2.1 Bearer A bearer is instantiated for the purpose of media communication through co-operation of the Media Control functional layer and the IP Transport plane. Figure 9 shows how the media control in conjunction with the transport plane provides the call with a bearer (media and transport) and that BC control the properties of the bearer. Sijben Expires 1 February 2001 14 TIPHON architecture 14 July 2000 Call Control +----+ + CC + +----+ | | Bearer Control +----+ + BC + +----+ | | Media Control +----|---+ + +----+ + + + MC + + + +----+ + + | + + | + Transport| + + +----+ + + + TR + + + +----+ + + + + Bearer + +--------+ Figure 9. Bearer Control. 8.2.2 End to end example In Figure 10 an example of given of the functions of the functional layers. Note that for simplicity the Services functional layer is not shown in Figure 10. 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Example of the functional layers and their communication with the IP Transport plane. Sijben Expires 1 February 2001 15 TIPHON architecture 14 July 2000 NOTE 6: Steps 3a and 3b may be initiated in parallel, but the completion of bearer establishment may occur prior to establishment of the call. The Figure 10 shows two terminals and two networks. Each network has its own transport network (the clouds at the bottom). In this example, the user at Originating terminal (A) requests a call to party B. (Note that the functional layers are also present in the terminals but this is not shown in the picture.) The originating network is asked to set up the call. As a result of the request for routing, the Call Control functional layer in the originating network is instructed to setup the call to the network in which the party B resides. The Call Control functional layers in both networks co-operate to establish this call, each communicating with its Service Control functional layer for authentication and call routing. The media communication is done through bearers. Within each network the Bearer Control functional layer co-operates with the appropriate terminal to establish the bearer properties. Between the networks the bearer entities communicate the inter-network bearer properties. The Media Control functional layers in each network allocate the appropriate firewalls/edge routers in the IP Transport plane and establish a QoS channel between them. If a media transcoding or other media transformation e.g. echo cancellation is necessary the Media Control functional layer performs it. 8.2.3 Relationship between BC, MC and TR entities Figure 11 shows how one bearer may be constructed out of multiple concatenated media flows each with its own transport. One Bearer Control entity communicates with multiple entities in the Media Control functional layer. Media flows through each entity in the Media Control functional layer. For each flow the entities in the Media Control functional layer will allocate transport by communicating with the appropriate transport entities. Sijben Expires 1 February 2001 16 TIPHON architecture 14 July 2000 CC info flow +----+ ---------------+ CC +---------------- +----+ | | BC info flow +----+ ---------------+ BC +---------------- +----+ /\ ........... / \ .. Bearer.. . / \ . . / \ . Media flows +----+ +----+ . ------------+ MC +--+ MC +---------- . +----+ +----+ . . /\ /\ . . / \ / \ . . / \ / \ . . / \/ \ . . +----+ +----+ +----+ . . + TR + + TR + + TR + . . +----+ +----+ +----+ . . . ............................. Figure 11. Relationship between BC, MC and TR entities. 8.3 Definition of reference points Reference points are (groups of) information flows subject of standardisation. The rest of this section describes the reference points, defines in the IP Telephony Application plane and shows how they can be combined to provide the Telephony Application over IP Networks. This section is structured as follows. Sections 8.3.1 and 8.3.2 provide the registration and call scenarios. The subsequent sections describe the reference points in more detail. 8.3.1 Registration Terminal . Serving . Intermediate . Home Registration FG . Network FG . Network FG . Network FG . . . . . . . . . +---------+ . Service . +---------+ + Service +...............................................+ User + + Profile + . Service control . + Profile + +---------+ . . . +---------+ | . . . | | S1 . . . | S2 | . | +--------------+ +--------------+ +--------------+ +--------------+ + Registration +R1+ Registration +R2+ Registration +R2+ Registration + +--------------+ +--------------+ +--------------+ +--------------+ Figure 12. Functions involved during the registration of a user. Sijben Expires 1 February 2001 17 TIPHON architecture 14 July 2000 8.3.2 Scenario 1 Orig. Orig. Int. Term. Term. Terminal Network Network Network Gateway +---------+ +---------+ +-------+ +-------+ +-------+ +-------+ + Service + + User + + Route + + Route + + Route + + Route + + Profile + + Profile + + + + + + + + + +---------+ +---------+ +-------+ +-------+ +-------+ +-------+ /\ \ / / / /\ || \ / / / || ||S1 S2\ /S3 /S3 /S3 ||S3 \/ \/ / / \/ +-----+ +----+ +----+ +----+ +----+ + Reg + + SC + + SC + + SC + + SC + +-----+ +----+ +----+ +----+ +----+ /\ /\ /\ /\ /\ || || || || || ||SC1 ||SC2 ||SC2 ||SC2 ||SC3 \/ \/ \/ \/ \/ +----+ +----+ +----+ +----+ +----+ + CC +===C1===+ CC +===C2===+ CC +===C2===+ CC +===C2===+ CC + +----+ +----+ +----+ +----+ +----+ /\ /\ /\ /\ /\ || || || || || || || || || || \/ \/ \/ \/ \/ +----+ +----+ +----+ +----+ +----+ + BC +===B1===+ BC +===B2===+ BC +===B2===+ BC +===B2===+ BC + +----+ +----+ +----+ +----+ +----+ /\ /\ /\ /\ /\ || || || || || ||N1 ||N2 ||N2 ||N2 ||N3 \/ \/ \/ \/ \/ +----+ +----+ +----+ +----+ +----+ + MC +===M1===+ MC +===M2===+ MC +===M2===+ MC +===M2===+ MC + +----+ +----+ +----+ +----+ +----+ /\ /\ /\ /\ /\ || || || || || ||T1 ||T2 ||T2 ||T2 ||T3 \/ \/ \/ \/ \/ +------------------------------------------------------------+ + IP Transport Plane + +------------------------------------------------------------+ NOTE: For the simplicity only one Call Control function is showed within each network. However, one network may include more than one call control function with a reference point similar to the C2 reference point. Figure 13. Reference points for the Scenario 1. Sijben Expires 1 February 2001 18 TIPHON architecture 14 July 2000 8.3.3 Scenario 2 Orig. Orig. Int. Term. Term. Gateway Network Network Network Terminal +-------+ +-------+ +-------+ +-------+ +---------+ + Route + + Route + + Route + + Route + + Service + + + + + + + + & UP + + Profile + +-------+ +-------+ +-------+ +-------+ +---------+ /\ /\ /\ /\ /\ || || || ||S3 || ||S3 ||S3 ||S3 ||S2 ||S1 \/ \/ \/ \/ \/ +----+ +----+ +----+ +----+ +-----+ + SC + + SC + + SC + + SC + + Reg + +----+ +----+ +----+ +----+ +-----+ /\ /\ /\ /\ /\ || || || || || ||SC3 ||SC2 ||SC2 ||SC2 ||SC1 \/ \/ \/ \/ \/ +----+ +----+ +----+ +----+ +----+ + CC +===C2===+ CC +===C2===+ CC +===C2===+ CC +===C1===+ CC + +----+ +----+ +----+ +----+ +----+ /\ /\ /\ /\ /\ || || || || || || || || || || \/ \/ \/ \/ \/ +----+ +----+ +----+ +----+ +----+ + BC +===B2===+ BC +===B2===+ BC +===B2===+ BC +===B1===+ BC + +----+ +----+ +----+ +----+ +----+ /\ /\ /\ /\ /\ || || || || || ||N3 ||N2 ||N2 ||N2 ||N1 \/ \/ \/ \/ \/ +----+ +----+ +----+ +----+ +----+ + MC +===M2===+ MC +===M2===+ MC +===M2===+ MC +===M1===+ MC + +----+ +----+ +----+ +----+ +----+ /\ /\ /\ /\ /\ || || || || || ||T3 ||T2 ||T2 ||T2 ||T1 \/ \/ \/ \/ \/ +------------------------------------------------------------+ + IP Transport Plane + +------------------------------------------------------------+ UP = User Profile NOTE: For the simplicity only one Call Control function is showed within each network. However, one network may include more than one call control function with a reference point similar to the C2 reference point. Figure 14. Reference points for the Scenario 2. Sijben Expires 1 February 2001 19 TIPHON architecture 14 July 2000 8.3.4 Scenario 3 Orig. Orig. Int. Term. Term. Gateway Network Network Network Gateway +-------+ +-------+ +-------+ +-------+ +-------+ + Route + + Route + + Route + + Route + + Route + +-------+ +-------+ +-------+ +-------+ +-------+ /\ /\ /\ /\ /\ || || || || || ||S3 ||S3 ||S3 ||S3 ||S3 \/ \/ \/ \/ \/ +----+ +----+ +----+ +----+ +----+ + SC + + SC + + SC + + SC + + SC + +----+ +----+ +----+ +----+ +----+ /\ /\ /\ /\ /\ || || || || || ||SC3 ||SC2 ||SC2 ||SC2 ||SC3 \/ \/ \/ \/ \/ +----+ +----+ +----+ +----+ +----+ + CC +===C2===+ CC +===C2===+ CC +===C2===+ CC +===C2===+ CC + +----+ +----+ +----+ +----+ +----+ /\ /\ /\ /\ /\ || || || || || || || || || || \/ \/ \/ \/ \/ +----+ +----+ +----+ +----+ +----+ + BC +===B2===+ BC +===B2===+ BC +===B2===+ BC +===B2===+ BC + +----+ +----+ +----+ +----+ +----+ /\ /\ /\ /\ /\ || || || || || ||N3 ||N2 ||N2 ||N2 ||N3 \/ \/ \/ \/ \/ +----+ +----+ +----+ +----+ +----+ + MC +===M2===+ MC +===M2===+ MC +---M2---+ MC +---M2---+ MC + +----+ +----+ +----+ +----+ +----+ /\ /\ /\ /\ /\ || || || || || ||T3 ||T2 ||T2 ||T2 ||T3 \/ \/ \/ \/ \/ +------------------------------------------------------------+ + IP Transport Plane + +------------------------------------------------------------+ NOTE:For the simplicity only one Call Control function is showed within each network. However, one network may include more than one call control function with a reference point similar to the C2 reference point. Figure 15. Reference points for the Scenario 3. Sijben Expires 1 February 2001 20 TIPHON architecture 14 July 2000 8.3.5 Scenario 4 Orig. Orig. Int. Int.CSN. Int. Terminal Network Network Network Network +-------+ +-------+ +-------+ +-------+ +-------+ +-------+ |Service| | User | | Route | | Route | | | | Route | |profile| |profile| | | | | | | | | +---+---+ +-----+-+ +-+-----+ +---+---+ | | +---+---+ |S1 |S2 |S3 |S3 | | |S3 +---+---+ ++-----++ +---+---+ | | +---+---+ | SC | | SC | | SC | | | | SC | +---+---+ +---+---+ +---+---+ | | +---+---+ |SC1 |SC2 |SC3 | | |SC3 +---+---+ C1 +---+---+ C2 +---+---+ C3 | | C3 +---+---+ | CC +-------+ CC +-------+ CC +----+ SCN +----+ CC +-- +---+---+ +---+---+ +---+---+ | | +---+---+ | | | | | | +---+---+ +---+---+ +---+---+ | | +---+---+ | BC | | BC | | BC | | | | BC | +---+---+ +---+---+ +---+---+ | | +---+---+ |N1 |N2 |N4 | | |N4 +---+---+ M1 +---+---+ M2 +---+---+ M3 | | M3 +---+---+ | M +-------+ M +-------+ M +----+ +----+ M | +---+---+ +---+---+ +---+---+ +-------+ +---+---+ |T1 |T2 |T3 |T3 +-----+---------------+---------------+-------------------------+-----+ | IP | +---------------------------------------------------------------------+ Figure 16a Left hand side of Reference points for the Scenario 4. Note that the figures overlap for readability. Sijben Expires 1 February 2001 21 TIPHON architecture 14 July 2000 Int. Int.CSN. Int. Terminating Terminating Network Network Network Network Terminal +-------+ +-------+ +-------+ +-------+ +-------+ +-------+ | Route | | | | Route | | User | | Route | |Service| | | | | | | |profile| | | |profile| +---+---+ | | +---+---+ +-----+-+ +-+-----+ +---+---+ |S3 | | |S3 |S2 |S3 |S1 +---+---+ | | +---+---+ ++-----++ +---+---+ | SC | | | | SC | | SC | | SC | +---+---+ | | +---+---+ +---+---+ +---+---+ |SC3 | | |SC3 |SC2 |SC1 +---+---+ C3 | | C3 +---+---+ C2 +---+---+ C1 +---+---+ + CC +----+ SCN +----+ CC +------| CC +---------+ CC + +---+---+ | | +---+---+ +---+---+ +---+---+ | | | | | | +---+---+ | | +---+---+ +---+---+ +---+---+ | BC | | | | BC | | BC | | BC | +---+---+ | | +---+---+ +---+---+ +---+---+ |N4 | | |N4 |N2 |N1 +---+---+ M3 | | M3 +---+---+ M2 +---+---+ M1 +---+---+ + MC +----+ +----+ MC |------| MC +---------+ MC | +---+---+ +-------+ +---+---+ +---+---+ +---+---+ |T3 |T3 |T2 |T1 +---+-------------------------+--------------+-----------------+------+ | IP | +---------------------------------------------------------------------+ Figure 16b Right hand side of Reference points for the Scenario 4. NOTE: For the simplicity only one Call Control function is showed within each network. However, one network may include more than one call control function with a reference point similar to the C2 reference point. 8.3.6 SC-Service reference points S1:Information flows at S1 provide the capability to store, retrieve and delete the registration ticket. S2:Information flows at S2 provide the capability to get and set properties in the User Profile. For the purposes of: User authentication, User authorisation, Call routing, User preferences, Allowed services and service options. S3:Information flows at S3 provide the capability to get call routing information and address translation. 8.3.7 SC-SC reference points R1:Information flows at R1 provide the capability required for a user to register with the Serving IPTN. It provides the capability to convey users ID, terminal ID, terminal capabilities etc. R2:Information flows at R2 provide the capability so that networks can exchange user registration and information related to user profile and subscription. 8.3.8 CC-SC reference points Sijben Expires 1 February 2001 22 TIPHON architecture 14 July 2000 SC1:Information flows at SC1 provide the capability to get a ticket on an existing registration session. SC2:Information flows at SC2 provide the capability to answer queries to the user profile. SC3:Information flows at SC3 provide the capability to answer access and routing requests for calls in the context of Network Functional Groupings. Input information may include called address/name, caller, calling domain. Output information may include next-hop address, preferences and constraints for the call parameters. 8.3.9 CC/BC-CC/BC reference points C1:Information flows at C1 provide the capability to establish, modify and terminate both calls and bearers to and from the terminal. C2:Information flows at C2 provide the capability to establish, modify and terminate both calls and bearers between non-terminal functional groupings. C3:Information flows at C3 provide the capability to establish, modify and terminate calls and connections between non-terminal functional groupings using an SCN. 8.3.10 MC-BC reference points N1:Information flows at N1 provide the capability to request, modify and delete media paths for the creation of a bearer in the context of Terminal Functional Grouping. N2:Information flows at N2 provide the capability to request, modify and delete media paths for the creation of a bearer and provides the capability to control an insertion of information (e.g. tones and announcements) into media flows in the context of Network Functional Grouping. N3 Information flows at N3 provide the capability to request, modify and delete media paths for the creation of a bearer in the context of Gateway Functional Grouping. N4:Information flows at N4 provide the capability to request, modify and delete media paths for the creation of a bearer and provides the capability to control an insertion of information (e.g. tones and announcements) into media flows in the context of Intermediate Gateway Functional Grouping. 8.3.11 MC-MC reference points M1:Information flows at M1 provide the capability to carry media flows between the terminal and the IPN. M2:Information flows at M2 provide the capability to carry media flows over the IPN. M3:Information flows at M3 provide the capability to carry media flows over the SCN. 8.3.12 TR-MC reference points T1:Information flows at T1 provide the capability to permit, modify and inhibit transport capabilities for the terminal, including Quality of Service, for the creation of a media flow. Sijben Expires 1 February 2001 23 TIPHON architecture 14 July 2000 T2:Information flows at T2 provide the capability to permit, modify and inhibit transport capabilities for the IPTN, including Quality of Service, for the creation of a media flow. T3:Information flows at T3 provide the capability to permit, modify and inhibit transport capabilities for the SCN, including Quality of Service, for the creation of a media flow. 9 Basic functional entities information flows This subclause contains the Message Sequence Charts (MSC) and definitions for primitives and their parameters for each reference point. Annex A contains an overview of functional entities, information flows, the Specification and Description Language (SDL) and functional entity actions from which the MSC diagrams in this subclause are derived. These sections are omitted for the sake of brevity. The interested reader is referred to the full document, which is publicly available and can be found at http://docbox.etsi.org/Tech-Org/TIPHON/Document/tiphon/07- drafts/wg2/DTS02003/ the current version is 0.10.8. Later versions will appear in the same directory. 10. Security Considerations The architecture as described in this document has a number of security hooks that will be filled in by the TIPHON security group. A re-release of the document is planned later this year that will incorporate these security elements. 11. References [1] ITU-T Recommendation E.164 (1997): 'The international public telecommunications numbering plan'. [2] ETS 300189 [3] ISO/IEC 11571 [4] ETSI TR101 300 'Description of Technical Issues V2.1.1'. [5] ETSI-TS101 313 v0.4.2 'Network architecture and reference configurations; Phase II: Scenario 1 + Scenario 2'. [6] TIPHON-DTR01007 http://docbox.etsi.org/Tech-Org/TIPHON/Document/ tiphon/07-drafts/wg1/DTR01007/ [7] TIPHON-DTS05009 http://docbox.etsi.org/Tech-Org/TIPHON/Document/ tiphon/07-drafts/wg5/DTS05009/ [8] TIPHON DTS02003 http://docbox.etsi.org/Tech-Org/TIPHON/Document/ tiphon/07-drafts/wg2/DTS02003/ version 0.10.8 and higher 12. Acknowledgements The document presented here was the result of hard work by the members of TIPHON WG 2. This group is chaired by Josef Vandenamele, the editor of the document is Jan Holm frequent contributors have been Jan Holm, Phil Mart, Steve Moore, Pekka Pessi, Paul Sijben, Marko Suoknuuti,Richard Swale. Many thanks to Scott Caszow for doing the text figures. Sijben Expires 1 February 2001 24 TIPHON architecture 14 July 2000 13. Author's Addresses Paul Sijben Lucent Technologies Huizen Netherlands Email: sijben@lucent.com Sijben Expires 1 February 2001 25