Setup: Synchronizing Service Level Descriptions (SLDs)

The Source Bank needs to be aware of the specific requirements and functionality of the Destination IPS and its member banks, so that it can collect the correct information from their customer. For example, the Source Bank needs to know the primary account format, which alias formats are accepted (if any), the maximum payment size that can be sent and whether confirmation of payee is possible.
The requirements and functionality for each IPS are recorded in a simple Service Level Description (SLD) file. (See IPS Service Level Descriptions for the full SLD specification.)
SLDs must be synchronised across the Nexus network, so that the Source Gateway can quickly provide the SLD information for any Destination IPS to the Source Bank.
The Source IPS sends its SLD to the Source Gateway, which shares it across the Nexus network
Each IPS is responsible for updating their local Nexus Gateway with any changes made to its SLD (1). These changes are likely to be infrequent (less than monthly). For example, if the maximum payment size for cross-border payments into the country is changed, that IPS must update its SLD and share this with the local Nexus Gateway. The local Nexus Gateway will then distribute the updated SLD with every other Nexus Gateway in the network (2).
These SLDs are used in Step 1 of the payment setup stage described below.

Message Flow

These message flow diagrams show the sequence of communication and messages between different participants in Nexus.
Triggered by the UpdateSLD API call.
Message flows for synchronisation of SLDs across the Nexus network