Loudcloud, Inc. Netscape Communications Corp. The Lightweight Directory Access Protocol (LDAP) [1] defines a network representation of a search filter transmitted to an LDAP server. Some applications may find it useful to have a common way of representing these search filters in a human-readable form. This document defines a human-readable string format for representing the full range of possible LDAP version 3 search filters, including extended match filters. This document replaces RFC 2254. See Appendix A for a list of changes relative to RFC 2254.