One question dear, what if there is no DRA and the user is a roamer with home routed traffic ,how does the visited network finds the home network /talk to home HSS if no DRA?
When a subscriber travels outside their home network's coverage area and connects to a visited network, they are considered to be roaming. In this scenario, the visited network needs to authenticate the subscriber and provide access to services as per their subscription plan. However, the visited network may not have access to the subscriber's authentication information or subscription profile, as these details are typically stored in their home network's HSS. To address this, roaming agreements are established between network operators. As part of these agreements, the visited network can request subscriber information and authentication from the subscriber's home network. This is where the concept of "roaming partner's HSS" comes into play. When a subscriber roams onto a visited network, the visited network communicates with the subscriber's home network's HSS to authenticate the subscriber and retrieve their subscription profile. This allows the visited network to provide services to the subscriber as per their home network's policies and service entitlements. In summary, the roaming partner's HSS refers to the Home Subscriber Server of the subscriber's home network, which is accessed by visited networks to authenticate subscribers and retrieve their subscription details when they roam onto foreign networks. This ensures seamless connectivity and service continuity for subscribers while roaming.
