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- Create a new JPA data structure to manage the information; or
- Augment the existing PdpGroup data structure to maintain the additional information. This could be done by changing the list of policies to a list of policy-info structures, where each object contained:
- policy name and version
- flag indicating whether the policy is being deployed or undeployed
- list of PDPs for which PAP is still awaiting the outcome of the PDP-UPDATE message
An advantage of approach #2 is that it's easier to transactionalize updates to the PdpGroup along with the list of waiting PDPs. One downside is the extra amount of data that must be retrieved when a PdpGroup is extracted from the DB.