Re: LDAP 3.1 Release Announcement

[Paul Barker <[e-mail]>]

> What are the advantages/disadvantages of LDAP versus the full protocol 
> stack version? If the answer is in a FAQ, please just send me a pointer.
> 
One possible advantage of LDAP is a performance benefit.  Clearly the
difference depends ultimately on what software/hardware you're running.  But
for a series of tests run from my workstation I got the following:

I built an ISODE DAP version of the DE user interface, and another version
with the U Mich LDAP libraries.  I then ran some well spaced tests
(to minimise caching effects) where I looked up an entry in another UK
university - this required a sequence of X.500 operations to resolve the
query.  The DAP client talked directly to DSA A.  The LDAP client
talked to an ldapd running on the same box as DSA A, and the ldapd talked to
DSA A.  In both cases DSA A had to forward the query to DSA B.
Average query times (in seconds) were as follows for sample sizes of about 400.

		Average		Median
DAP DE		11.43		9.5
LDAP DE		 8.67		3.8

I admit I had suspected that the benefit of the smaller LDAP processes might
outweigh the costs of protocol conversion, but I was surprised at the size
of the disparity.  

Paul