X.500 Performance with Large Databases and OSInet [chapter]

P. V. Rajeev, S. V Raghavan, Ashok K. Agrawala
1995 Computer Networks, Architecture and Applications  
The X.500 directory provides a powerful mechanism for storing and retrieving information about objects of interest in the networking world. The rapid increase in the deployment of the directory has resulted in a very large amount of data in the global directory. Hence, the need arises for the development of a model which predicts the performance of the directory in an internet environment with large amount of data. In this paper, we present a deterministic model for predicting the performance
more » ... X.500 directory operations. Actual measurements are carried out in a real life environment, with the directory having a large amount of data distributed across the internet. The model is validated by comparing the results of these actual measurements with the predicted values. The application of the model for the selection of DIT structure in a wide area network is explained. X.500 performance with large databases and OS/net 233 1 INTRODUCTION With the rapid expansion in the electronic communication, there is a growing need for an organized global information service. The X.500 directory provides such a powerful mechanism for storing and retrieving information about objects of interest in the networking world (CCITT (1988), Huitema (1989), Bumbulis et al.(1993)]. X.500 directory defines an architecture whereby the directory can be distributed over an arbitrary number of systems. Each system manages a portion of the global directory. Typically, in the X.500 directory, the information is distributed and managed across the network of many autonomous administrations. These systems are integrated into a single directory by a set of protocols. The directory stores information about objects and defines a hierarchical relationship between objects stored in the directory. The hierarchical structure reflects the national and organizational structure of the real world objects. The X.500 directory was originally designed for use with X.400 message handling systems (MHS) [CCITT (1988)]. Message handling system uses directory for a variety of purposes including: retrieval of 0/R address when 0/R name is given, user friendly naming of users in the MHS, expansion of distribution lists, e-mail routing, etc. To provide these services to the MHS, the directory must store information about all e-mail users in the network. The number of e-mail users in the network itself will be of the order of millions. A recent survey on the usage of internet indicated a very high rate of increase in the number of users. A large amount of information has to be stored in the directory to cater to the needs of MHS. Apart from MHS, djrectory is now being used for a variety of other applications. For example directory is now used to store the topology and service related information about communication networks (Ma.nsfield et al.(1993), Hong et al.(1992a), Hong et al.(1992b)], to map object names to internal object identifiers in object based distributed operating systems (Rennesse et al.], to store bibliographic information (Barker (1992)], to store the information about ftp archives (Barker (1993)], and so on. Once all these applications start using the directory to store information, directory will be used extensively and an enormous amount of data will be stored in the directory. The X.500 directory deployment in the internet is now progressing at a very fast pace. Presently, there are more than 450 Directory System Agents (DSAs) spanning 35 nations, covering a total of more than a million entries (Goodman (1992) ]. The growth rate is found to be significant, with about 150 DSAs added every year since November 1990, with a proportional increase in the number of entries. With this rate of increase in the deployment of directory in the internet, the internet directory will soon be populated with enormous amount of information. The information about the e-mail users itself will be substantial. The internet directory is also used for storing information about various services available in the internet. Directory helps in giving an integrated view of the
doi:10.1007/978-0-387-34887-2_14 fatcat:rzymtr6nnjh55kl4kkq6p3bd3a