This TS defines the stage one description of the Support of Mobile Number Portability between networks in the same country as well as North America cross-sector portability (i.e.,. number portability between fixed and 3GPP system). Stage one is an overall service description, primarily from the service subscriber's and user's points of view, but does not deal with the details of the human interface itself. Mobile Number Portability (MNP) is applicable only to those telecommunication services identified by an MSISDN. This specification includes information applicable to network operators, service providers and terminal, switch and database manufacturers. This specification contains the core requirements for the Support of Mobile Number Portability between network operators in the same country as well as North America cross-sector portability which are sufficient to provide a complete service. Other cross-sector portability options (e.g. number portability between fixed and mobile networks outside the North American Region) are outside the scope of this technical specification. It is highly desirable however, that technical solutions for MNP should be sufficiently flexible to allow for possible enhancements, e.g. cross-sector number portability, and MNP between analogue and digital mobile networks. Additional functionalities not documented in this specification may implement requirements which are considered outside the scope of this specification. This additional functionality may be on a network-wide basis, nation-wide basis or particular to a group of users. Such additional functionality shall not compromise conformance to the core requirements of the service. Porting between Service Providers (i.e. service provider portability) which does not involve a change of Network Operator is outside the scope of this specification. The relationship between Service Providers and Network Operators is outside the scope of this specification. The relationship between a Service Provider and subscriber is outside the scope of this specification. The interface between the User Equipment (UE) and any external applications are outside the scope of this specification. Charging principles are outside the scope of this specification except where explicitly stated in the text.

The following documents contain provisions which, through reference in this text, constitute provisions of the present document.

• References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific.
• For a specific reference, subsequent revisions do not apply.
• For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document.

Mobile Number Portability cannot be offered to a subscriber as a stand alone service. Mobile Number Portability is applicable to all teleservices (e.g. SMS, voice, fax), IP Multimedia services and bearer services (e.g. data), except for TS12 (emergency call). The implementation of MNP shall be flexible enough to apply to each DN of a subscriber separately. Where the DNs used in the donor network are ported to different recipient mobile networks then a new IMSI/IMPI (and SIM/USIM/ ISIM) will be required for each recipient network. The basic and supplementary services provisioned in the recipient network shall not be dependent on those that were provisioned in the donor network.

Mobile Number Portability (MNP) is the ability for a mobile subscriber to change digital mobile subscription networks within the same country whilst retaining her original DN or DNs. Additional regulatory constraints apply in North America. North American GSM Number Portability (NAGNP) is the ability for a subscriber to change subscription between North American GSM networks and other subscription networks within an FCC regulated geographical area within North-America. The IMSI/IMPI shall not be ported, hence the recipient mobile network of the porting process will issue a new IMSI/IMPI for the ported subscription. The porting process may, but need not, include a change in service provider. The ported subscriber can use exactly the same services as non-ported customers in the same subscription network. That is: whether the DN of a subscriber belongs to a subscription network or is ported to the subscription network shall have no influence on the services offered to the customer by that subscription network. The services offered by the number range owner network and/or the donor network have no influence on the services offered by the subscription network. When a subscriber ports a DN to a new network then the donor network no longer provides support for the services of the ported number (this includes supplementary and value added services). A network can be a donor of numbers and a recipient of numbers. A DN can be ported more than once; a ported number can be ported back to its number range owner network. Even after multiple portings, the technical solution shall involve only the number range owner network and recipient network. The solution for MNP/NAGNP shall have a minimal adverse effect upon the quality of service offered to ported and non-ported subscribers. It may be the case that the quality of service for ported and non-ported subscribers differs slightly (e.g. due to additional call set-up delay). Any additional delay in call set-up to ported numbers shall be minimised. The process of porting a number may involve a disruption in service to the customer. The time that no service is available shall be minimised. The technical implementation of the support of MNP/NAGNPin a network should not impede number availability and efficient use of numbers. The technical implementation for the support of MNP/NAGNPshall not involve loss of functionality in the number range owner, donor or subscription network. The technical implementation of MNP/NAGNPshall support optimisation of the use of network and inter-network resources so as to minimise costs associated with transport of traffic and/or appropriate signalling and/or processing activities (e.g. optimal routing). In addition, for the porting process an efficient and effective way is needed to exchange porting information between all types of network operators.

Mobile Number Portability is offered to all subscribers of telephone services subject to regulatory requirements. A porting process is initiated at a subscriber's request on their selected DN(s) with the relevant networks. Initiation of the porting process is an off-line administrative process and cannot be invoked via a specific MMI on the hand-set. After successful porting the subscriber, is able to use the provisioned telephone services and network specific services of the subscription network as offered to non-ported subscribers on that network. Porting will effectively initiate a new subscription As part of the porting process, the donor, number range owner and recipient networks shall update their relevant network elements in order to perform the porting. After the porting process is complete, the subscription details related to the ported DN on the donor network shall not be required and can be deleted. Therefore, only the number range owner network and the recipient network are involved in the MNP/NAGNPsolution for support of service to the ported subscriber. The originating network may not be aware of the ported nature of the number; therefore the technical solution shall work even if networks other than the number range owner and recipient have no knowledge of the ported nature of the number. When a ported subscriber takes an additional DN at her subscription network that additional DN should not have to come from the number range owner network(s) of the subscriber's ported numbers. Where number ranges are assigned to network operators, the number range owner network shall receive the ported number back from the recipient network when the subscriber relinquishes the ported number, i.e. when the ported number ceases to be an active service number.

Service related data (e.g. numbers used in the call-forwarding service, etc.) may not be transferred to the recipient network during the porting process.

As a consequence of MNP, the DN of a subscriber may no longer explicitly identify the subscription network of that subscriber.

The support of mobile Number Portability in a network shall not affect the handling of supplementary service for the subscribers, i.e. there shall be no difference in the handling of the supplementary services between ported in and normal subscribers of the same network.

All services offered in co-operation with other types of networks shall still be offered in combination with MNP. This includes the basic services, all supplementary services and all network features.

Enough information shall be collected to allow different tariffs to be applied to calls and short messages in the following case:

• The calling subscriber is roaming in her home PLMN
  and
• The called subscriber is a subscriber of any of the PLMNs in the country of the calling subscriber's home PLMN

In this case the collected information shall allow to distinguish between

• Calls and short messages directed to a called subscriber who subscribes to the calling subscriber's home PLMN
• Calls and short messages directed to a called subscriber who does not subscribe to the calling subscriber's home PLMN.

Enough information should be collected to allow the involved networks to workout inter-network charging.

Lawful interception shall be possible on a ported MSISDN.