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Re: Problems with multiple names per OID

Frank Strauß wrote:

I guess this is kind of an FAQ, but I could not find an explanation so far. If it is an FAQ, maybe someone give me just a pointer to the right information.

There are several cases where multiple names are defined for a single OID, e.g. core.schema defines the names "street" and "streetAddress" both for The Administration Guide says that when attributes are sent they are labeled with the first name. However, the other names are also valid in requests. Now the problem is that some LDAP clients send names in their requests that are known to the LDAP server as "secondary" names, resulting in responses with other names than the ones in the request. This results in clients not being able to process the response correctly, although the requested data is available and even sent back to the client.

Examples are Mozilla Thunderbird and Apple Addressbook which use different (but only one) names for OID and others.

My personal impression (though I'm new to LDAP, but have quite some experience with SNMP/SMI, which is also heavily based on ASN.1) is that LDAP's design is broken in that it does send non-unique labels instead of unique (and more compact) OIDs in the protocol. But maybe, I'm just missing a way how to handle the problem correctly.

I'd agree that LDAP's design is deficient here. Certainly this problem does not happen with X.500 DAP. I believe that you can use the rewrite overlay and attribute mapping to handle this now. The relay backend may also be useful.

 -- Howard Chu
 Chief Architect, Symas Corp.       Director, Highland Sun
 http://www.symas.com               http://highlandsun.com/hyc
 Symas: Premier OpenSource Development and Support