Question: What is a key characteristic of the Connection Oriented Data Transfer Service for RNSAP over the Iur interface, as expected from the signalling transport?
Option 1: Guaranteed delivery of RNSAP messages out of sequence, with no notification upon connection break.
Option 2: In-sequence delivery of RNSAP messages, with notification to RNSAP if the signalling connection breaks.
Option 3: Best-effort delivery of RNSAP messages without guaranteed sequencing or connection failure notifications.
Option 4: Scheduled batch delivery of RNSAP messages, irrespective of individual UE connections.
Explanation: The correct answer highlights a crucial aspect of the Connection Oriented Data Transfer Service for RNSAP. The in-sequence delivery ensures that messages are processed in the intended order, which is vital for maintaining the integrity of the signaling process between RNCs (Radio Network Controllers). Additionally, notifying RNSAP upon a signalling connection break enables prompt error handling and recovery mechanisms to maintain network reliability and user experience, especially since each active UE has its own signalling connection.