ere each cell has a list of neighboring cells (usually of the same radio technology) for handover. The same principle can be applied in the WiMAX and EPS integrated network. This solution for neighbor cell discovery creates a need for inter-technology measurement scheduling and coordination, which might be cumbersome and will require all terminals to have dual receivers. Alternatively, if there is a need to minimize the modifications of legacy radio systems, the neighbor cell information may not be broadcast on radio channels but rather be retrieved by the UE from a special functional entity in the network. Such an entity has been standardized by 3GPP in order to facilitate discovery of non-3GPP accesss (like WiMAX), and is termed as ANDSF [2-8]. ANDSF: The ANDSF contains data management and control functionality necessary to provide network discovery and selection assistance data as per operators' policy. An ANDSF element located in the home PLMN of a UE is referred to as the Home-ANDSF (H-ANDSF) for this UE, whereas an ANDSF element located in the visited PLMN of a UE is referred to as the Visited-ANDSF (V-ANDSF) for this UE. The ANDSF is an optional element in the network architecture and thus a UE may or may not be able to interact with an H-ANDSF and/or with a V-ANDSF. The UE-ANDSF interaction can take place via any 3GPP or non-3GPP access technology that can be used by the UE to access EPC. This function can be considered a dynamic database that is queried by mobiles (e.g., with a specific protocol over IP) whenever they need to discover neighbor cells of specific or any radio technology type. It is easy to recognize that such a discovery solution avoids any impact on the radio systems and the associated cost of upgrade. E2E Network Architecture and Mobility Management 3GPP IP Access or Trusted/Untrusted H-ANDSF Non-3GPP IP Access H-ANDSF HPLMN VPLMN 3GPP IP Access or Trusted/Untrusted V-ANDSF Non-3GPP IP Access Figure 11.6 Roaming/Non-roaming architecture for ANDSF. Reproduced with permission from 2009 3GP