Cisco Cisco Unified MeetingPlace Directory Services Manuale Di Manutenzione

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Chapter 5  Managing MeetingPlace Directory Services 
MeetingPlace Directory Services System Manager’s Guide Latitude Communications
Using a Correlation Rule
In a MetaLink agreement, correlation rules are used to link 
entries in two directory servers. It is an important part of the 
synchronization process, because it determines which entry in the 
destination server corresponds to which entry in the source server. 
Only one correlation rule needs to give a match for a destination 
entry to correlate with a source entry. Each rule consists of at least 
one attribute mapping, where each source and destination 
attribute needs to be the same value in order for the rule to 
correlate.
You can consider a correlation rule to be part of a logical OR 
statement, and the attribute mappings within the correlation rule 
part of a logical AND statement.
A correlation rule accommodates both simple and complex 
correlations. The directory server may have a natural correlator 
(e.g. unique employee number) or a combination of correlators 
(e.g. first name, last name, and department number) that establish 
a correlation rule. 
You can combine a number of correlation rules to create complex 
rules which include logical AND operators, string constants and 
equality tests.
It is important to consider which attributes to use when creating a 
correlation rule. The value, or combination of values, must be 
unique in both MeetingPlace and your corporate directory server. 
If the value of these attributes is not unique, multiple entries 
could correlate into a single entry. Also, the attributes used in the 
correlation rule must exist in all entries in both MeetingPlace and 
your corporate directory server. 
Additionally, it is important to remember that if correlation can’t 
be made between entries in MeetingPlace and your corporate 
directory server, then a new entry will be created using BootStrap 
attribute mapping. Therefore, a correlation rule must be defined 
properly to ensure this doesn’t happen if there are corresponding