2013 marked a rapid increase in interest to improve cellular to Wi-Fi interoperability – not just from mobile operators, but also from cable operators, fixed line operators and enterprises. The interest is truly global as organizations in every region are developing strategies to leverage Wi-Fi for a variety of reasons, including network congestion relief, improved in-building coverage, and ability to offer lower cost wireless service plans. However, in order to achieve truly seamless interoperability across heterogeneous networks from any provider, the industry needs to resolve challenges associated with connectivity, authentication, session persistence and traffic management. This is the objective of several emerging industry standards, including a set being developed by the 3rd Generation Partnership Project (3GPP) known as Access Network Discovery and Selection Function, or ANDSF.
What’s Driving the Market for ANDSF?
The increasing availability of multiple wireless network types has driven a need to address discovery and access of these networks by mobile devices, prompting standards organizations such as 3GPP to take action and create a policy specification standard to be enforced by a mobile device. The first ANDSF specification was introduced in 3GPP release 8. Since then, it has been enhanced and expanded to its recent release 12.
An Overview of the ANDSF Architecture
The ANDSF specification allows mobile network operators and non-3GPP service providers, such as cable companies with Wi-Fi networks, to specify policy, rules and parameters to guide the device to detect and connect to heterogeneous networks.
At a high level, the ANDSF specification covers the following areas:
- Metadata management structure, compatible with the OMA Device Management (OMA-DM) Management Object (MO) and protocol, which defines message format, application authentication security, provisioning and message level security
- Network Discovery Information (NDI)
- Inter-System Mobility Policy (ISMP) rule and selection criteria
- Inter-System Routing Policy (ISRP) rule and selection criteria
- Home and visiting ANDSF topology (H-ANDSF and V-ANDSF)
The environment for mobile connectivity is an increasingly complex mix of network technologies, forcing wireless service providers, infrastructure vendors, mobile equipment manufacturers and software providers to improve interoperability among these technologies. In order to resolve this gap, the 3GPP organization has developed the ANDSF set of standards to modernize and optimize intelligent network selection and traffic management functions.