1. Directory Service X.500

2. X.500 – Idea  Idea : look up people and data  User-friendly way  By name, department, or organization  Global White Pages directory  1984 CCITT and ISO started development

3. X.500 – What is it?  1990 First official ISO implementation  Electronic directory  People and their data in an organization  Can be part of a global directory  Available via Internet or Private Net (LAN/VPN)

4. X.500 – Directory Service  Many electronic directories  Organized in a single global directory  organized in a "tree"  common "root" directory

5. X.500 – Principle I  Entries at each level of tree must have certain attributes  Some optional attributes established locally Own implementations possible must adhere to the basic schema  one or more central places manage directories.  DCE (Distributed Computing Environment)

6. X.500 – Principle II  DSA Directory System Agent reflects local directory one organization or group of organizations.  DSAs interconnected by Directory Information Tree (DIT).  X.500 as part of Distributed Computing Environment (DCE)  DCE in Global Directory Service (GDS).

7. X.500 – Principle III  UI for access to DSAs = Directory User Agent (DUA).  DUAs include: cmdline progs like whois, finger programs that offer a graphical user interface.

8. X.500 – Directory Service

10. X.500 – Examples  InterNIC organization that supervises domain name registration in the U.S.  Esnet maintains X.500 data for all the U.S. national laboratories.  Many US Universities use X.500 route e-mail provide name lookup (LDAP)

11. X.500 – Examples  Lotus Domino relies on X.500 (since v.5)  Internet Provider dial-up nodes / DNS  Microsoft Exchange Server  Oracle Internet Directory  Peerlogic Livecontent Directory  Siemens DirX Server  Umich slapd/slurpd  Computer Associated ETrust Directory  and others

12. X.500 – Any Questions???  Thanks for your Attention  References:  RFC1632  www.isi.salford.ac.uk\staff\dwc\Version.Web\Contents.htm