Description:
This paper describes some work which helps users of the X.500 directory to understand the unevenness of quality of service (QOS) concomitant with a widely distributed directory. In particular a user may see highly variant response times and availability of information for different parts of the directory.The paper discusses, and dismisses, two possible sources of QOS information. I use a third approach whereby a directory user interface maintains a record of response times and information availability and uses this database to provide a user with feedback about those aspects of the service. The DE user interface has been modified to incorporate this facility. The technique used also provides directory managers with a view of directory performance from a user's perspective.The work described has been partly funded by the PARADISE projects, through the European COSINE project and VALUE programme.