Donor Network

Description

In the context of mobile number portability (MNP), the donor network is the subscription network that currently holds the mobile number and from which the number is being ported to another network. When a subscriber decides to change their mobile operator while keeping their existing phone number, the process involves two primary networks: the donor network (the old operator) and the recipient network (the new operator). The donor network is responsible for releasing the number and ensuring that any active services associated with that number are properly terminated or transferred. It may or may not be the original number range owner; in some cases, the number may have been previously ported from another network, making the donor network an intermediate holder rather than the original assignee.

The donor network plays a critical role in the porting process, which is governed by 3GPP specifications such as TS 22.066 (Support of Mobile Number Portability) and TS 21.905 (Vocabulary for 3GPP Specifications). The porting process typically involves a series of signaling exchanges between the donor and recipient networks, often facilitated by a central reference database or clearinghouse. The donor network must validate the porting request, confirm that the subscriber has no outstanding obligations (e.g., unpaid bills or active contracts), and then coordinate the release of the number. Once the porting is complete, the donor network must update its routing tables to ensure that calls and messages to the ported number are correctly routed to the recipient network.

From an architectural standpoint, the donor network interacts with several core network elements, including the Home Location Register (HLR), the Mobile Switching Center (MSC), and the Short Message Service Center (SMSC). These elements must be updated to remove the ported number from the donor network's databases and to redirect any incoming traffic to the recipient network. The donor network also plays a role in the porting notification process, informing other networks and service providers about the change to ensure seamless service continuity for the subscriber.

The concept of a donor network is essential for enabling competition and consumer choice in the telecommunications market. Without number portability, subscribers would be locked into their current operator, which could stifle innovation and lead to higher prices. By allowing numbers to be ported, the donor network concept ensures that subscribers can switch operators without losing their identity, thereby promoting a more dynamic and competitive market.

In summary, the donor network is a fundamental entity in the mobile number portability ecosystem. It is the network from which a number is ported, and its responsibilities include validating the porting request, releasing the number, and updating its systems to reflect the change. The donor network may or may not be the original number range owner, and its role is critical for ensuring a smooth and efficient porting process.

Purpose & Motivation

The donor network concept exists to facilitate mobile number portability (MNP), which allows subscribers to retain their phone numbers when switching operators. Before MNP was introduced, subscribers had to change their numbers when changing operators, which was inconvenient and could lead to lost contacts and business opportunities. The donor network is the entity that releases the number, enabling the recipient network to take over its management. This promotes competition among operators, as subscribers can freely choose the best service without the hassle of changing numbers.

Historically, number portability was first mandated in several countries in the late 1990s and early 2000s. The 3GPP standardized the technical aspects of MNP in specifications like TS 22.066, which defines the requirements for MNP across different releases. The donor network is a key concept in these specifications, as it defines the responsibilities of the old operator during the porting process. The donor network must ensure that the porting is executed without disrupting the subscriber's service and that all necessary updates are made to routing and billing systems.

The donor network also addresses the need for regulatory compliance. Many national regulators require operators to support number portability within a specified timeframe and to ensure that the process is transparent and efficient. The donor network's role is thus not only technical but also regulatory, as it must adhere to these requirements to avoid penalties and maintain a competitive edge.