3.1.5.4 Polling for Cache Consistency

The User Name Mapping Protocol client uses GETCURRENTVERSIONTOKEN_PROC to periodically check the server for cache consistency. Whenever any of the user or group account mappings on the server change, the tokens returned in the response to GETCURRENTVERSIONTOKEN_PROC are different, at which point the client MUST discard its cached copy of all the mappings in their entirety and enumerate the new set of mappings from the server.

If CurrentVersionTokenHighPart and CurrentVersionTokenLowPart in the GETCURRENTVERSIONTOKEN_PROC reply are the same as those from the previous enumeration, there have been no changes to any map records, and any cache of map records being maintained by the User Name Mapping Protocol client is still valid. If either CurrentVersionTokenHighPart or CurrentVersionTokenLowPart in the GETCURRENTVERSIONTOKEN_PROC reply differs from those returned by the previous enumeration, the mapping records have been updated, and the User Name Mapping Protocol client MUST consider the local cached copies of the mapping records as out of date and MUST repeat the enumeration to get the updated set of mapping records.