Ported Subscriber

Description

A ported subscriber is defined in 3GPP TS 21.905 and TS 22.066 as the subscriber of a ported number. In the context of mobile number portability (MNP), the ported subscriber is the individual or entity that has exercised their right to retain their MSISDN while changing from a donor network operator to a recipient network operator. This term is essential for distinguishing between subscribers who have ported and those who have not, particularly in the context of service provisioning, charging, and regulatory reporting.

The ported subscriber is associated with a specific MSISDN that has undergone the porting process. When a subscriber ports their number, the subscription data — including IMSI, authentication credentials, and service profile — is transferred to the recipient network. However, the MSISDN remains the same. The ported subscriber is therefore reachable via the same number but is served by a different network infrastructure. This requires the recipient network to update its Home Location Register (HLR) or Home Subscriber Server (HSS) with the ported subscriber's data, and it requires the donor network to remove or deactivate the subscription.

From a routing perspective, the ported subscriber's number must be correctly resolved when incoming calls or messages are received. Networks use databases such as the Number Portability Database (NPDB) or Central Reference Database to determine which network currently serves the ported subscriber. In IMS and VoLTE environments, ENUM queries and SIP routing are used to locate the ported subscriber's serving Call Session Control Function (S-CSCF). The ported subscriber's identity is thus a key input to these routing decisions.

The term 'ported subscriber' is also relevant in regulatory and commercial contexts. Regulators may require operators to report on the number of ported subscribers, porting times, and any issues encountered. For operators, ported subscribers represent both an opportunity (gaining new customers) and a challenge (managing the technical and administrative aspects of porting). The 3GPP specifications provide a common vocabulary to ensure that all parties — operators, regulators, and vendors — use consistent terminology.

In summary, a ported subscriber is the human or organizational user behind a ported number. The term encapsulates the subscriber's relationship with the ported MSISDN and highlights the need for coordinated technical and administrative processes to ensure seamless service continuity.

Purpose & Motivation

The term 'ported subscriber' exists to provide a clear and unambiguous reference to the individual or entity that has undergone the number porting process. In the telecommunications industry, it is essential to distinguish between subscribers who have ported their numbers and those who have not, because the technical and commercial treatment of these two groups can differ significantly. For example, routing calls to a ported subscriber requires a database query to determine the current serving network, whereas calls to a non-ported subscriber can be routed directly based on the number range.

From a regulatory perspective, the concept of a ported subscriber is important for monitoring the effectiveness of number portability regulations. Regulators often require operators to report statistics on ported subscribers, such as the number of successful ports, the average time taken to port, and the number of porting requests rejected. These metrics help ensure that operators are complying with regulations and that subscribers are not facing undue barriers when switching networks.

Commercially, ported subscribers are a key focus for operators' marketing and retention strategies. Since ported subscribers have demonstrated a willingness to change operators, they may be more open to competitive offers. At the same time, operators must ensure that ported subscribers receive the same quality of service as non-ported subscribers, which requires robust technical processes. The 3GPP definition of 'ported subscriber' in TS 21.905 and TS 22.066 provides a standardized term that facilitates communication and coordination among all stakeholders.