Various programs support LDAP as a source of configuration data and, more commonly, account information and access control lists. These programs need an LDAP server to always be online, or otherwise they cannot perform their function. Another potential problem is that configuration and access control may concentrate on one site, which is especially problematic when complex group queries are needed to decide on privileges.

Although this approach works for some programs, not all do actually support LDAP, not all support the various schemes in existence and the ability to access LDAP itself may be authenticated in various ways, and a diversity of programs doing this leads to a choice for a common-least-denominator of security. Probably a password stored in the memory space of the program, together with all its application frivolities.

Pulley relies on LDAP SyncRepl to stay as close to live updates as possible, without resorting to polling.

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