Some numbering schemes shall be fully independent of the supporting serving network and the home environment, allowing users to transfer this number to another home environment. For further information see TS 22.066.
An MSISDN shall be allocated to each new user at the start of a subscription. This number may be allocated from one of several numbering domains. For example:
home / serving environment numbering scheme;
national numbering scheme;
regional numbering scheme;
global numbering scheme.
A user shall be able to move subscription from one home environment to another without changing the MSISDN provided that the new home environment offers service in the same geographic domain. It is envisaged that home environment s will be able to allocate MSISDNs from each of these domains as required.
Since 3GPP specifications aim to be aligned with IMT-2000, a primary goal in numbering is the provision of global user numbering in line with steps taken by the ITU - SG2.
The numbering scheme and network implementation chosen shall allow for international/global evolution.
A user may wish to use private numbers for the purposes of calling frequent numbers. Therefore there is a requirement for the use, by the user, of Private Numbering Plans (PNPs). These schemes may belong to the user himself, to a home environment or a third party.
The standards shall support the possibility of allowing the bearer service associated with an MT call to be implicitly defined by the destination MSISDN, for example to use a different MSISDN to establish voice, fax or data . It will be possible for multiple MSISDNs to be associated with a single subscription.
The standards shall support the possibility of allowing MT calls of different bearer types ( e.g. voice, fax, data) to be routed to a single MSISDN. It is recognised that the implementation of this may depend on the availability of bearer information associated with an incoming call from the adjoining transit network. In particular the standards will support this possibility in the case of an adjoining ISDN transit network.
The 3GPP system shall support the possibility to assign an additional MSISDN, in addition to the original MSISDN, to a user with a connection to the PS CN domain. If this additional MSISDN is available it shall be used for correlation of CS and IMS in voice call and service continuity as well as IMS Centralized Service. In this case the original MSISDN may be used for charging and OA&M purposes and forwarded to the PS gateway to other packet data networks.
The implementation of the numbering scheme used shall allow for optimal routing; i.e. routing shall not take place simply on the number dialled.
See TS 22.079 for some scenarios for the CS CN domain. Optimal routing for IP services is supported by the All-IP Network .
In 3GPP the identity of a subscriber is encoded in a identity module application which is contained on a UICC or on a GSM SIM card. The GSM SIM card is a removable component of the User Equipment; UICC can be removable or also embedded. Three types of identity modules are used in the 3GPP system:
Universal Subscriber Identity Module (USIM)
IMS Subscriber Identity Module (ISIM)
Subscriber Identity Module (SIM) according to GSM
In the 3GPP system each subscriber shall be uniquely identifiable.
The serving networks shall be able to authenticate any subscriber that roams onto their network
If a UE, that is registered on the serving network, contains a GSM SIM card or a UICC containing a identity module application, the serving network shall be able to identify the associated home PLMN.
It is a requirement that the terminal can be uniquely identified by the home environment and serving network. This shall require a terminal identity scheme which uniquely identifies each terminal, see TS 22.016.
Home / serving environments need to route communication to the current location of the user. This shall require a identity scheme which uniquely identifies the serving environment and shall be used for routing purposes.
A mobile virtual network operator (MVNO) is a service provider that does not have its own radio access network, but resells wireless services, typically under their own brand name, using the network of a host PLMN operator.
It should be possible to uniquely identify subscribers belonging to a particular MVNO.
The User Interface (MMI) from the end-user's point of view should be as flexible as possible while still meeting the general service requirements. In addition it should be capable of being updated so as to meet new services which are still to be envisaged.
In general the following principles should be encompassed:
activation of services should be as simple as possible with minimum input expected from the user;
feedback, to the user from the various services, should be meaningful;
any error recovery procedures provided should be simple to understand and execute.
input from the user and information to the user should be provided in alternative selectable modes in order to match user capabilities, preferences and situation.
However, a detailed specification for the User Interface shall not be defined. In particular given the global nature of the third generation systems, for different regions of the world, different criteria will determine the implementation of the User Interface. Also it is unlikely that there will be a single common handset which will meet all the service requirements and therefore a common User Interface would be impractical.
Given the flexibility of the services, there should be a wide range of User Interface possibilities. These possibilities include simple terminals with a single on/off button through to complex terminals providing support to hearing/visually impaired users.
Control of CS CN Domain supplementary services (TS 22.004), may use MMI procedures specified in TS 22.030 and existing MMI related UE features (Annex A) may also be used. In particular the following features are highly desirable for uniform UE implementation where appropriate:
Mapping of numeric keys to European alphabetic keys to ensure compatible mnemonic dialing as defined in TS 22.030,
"+" key function to enable one key international access as defined in Annex A