Processing MAP-to-Diameter Transactions

The processing of a MAP-to-Diameter transaction involves various steps:

1. When an MD-IWF receives a MAP request message from an SS7 Node attempting to open a MAP dialogue that MD-IWF is able to process, it allocates a MD-IWF Pending Transaction Record (MD-IWF-PTR) for storing the MAP query message(s) for the MAP procedure.
2. MD-IWF converts one or more MAP request messages into a single Diameter Request message, starts a Diameter Transaction Timer and then forwards the Diameter Request message to a DM-IWF using the services of ComAgent.
3. When DM-IWF receives a Request message from an MD-IWF, it allocates a DM-IWF Pending Transaction Record (DM-IWF-PTR) for storing MD-IWF's address (used for sending the Answer response), and attempts to forward the Diameter Request message to DRL. DM-IWF does not start a DM-IWF Pending Answer Timer as the ownership of the transaction is transferred to DRL.
4. If DM-IWF successfully enqueues the Diameter Request message on DRL's Request Message Queue, it will send a Success Response to the ComAgent reliable transfer transaction. This frees the ComAgent transaction. Otherwise, DM-IWF sends a Failure Response to the ComAgent transaction and DM-IWF processing of the transaction is complete
5. When an Answer is received from the peer Diameter node, it is received by DRL and forwarded to DM-IWF on the DA-MP. When DM-IWF receives a Diameter Answer message response from DRL, it forwards the Answer message to the MD-IWF SS7-MP which initiated the transaction and DM-IWF processing of the transaction is complete.
6. When MD-IWF receives the Diameter Answer response, it uses the Transaction ID to find the MD-IWF-PTR for the transaction. If a MD-IWF-PTR is found, it converts the Diameter Answer message into a MAP ack message response and the MAP dialogue is closed and the MD-IWF-PTR is deallocated. Otherwise, MD-IWF will discard the Answer.