Presented 3 November 1997 at the DECUS U.S. Chapter Symposium in
Anaheim, as Session MM005.
Most mail systems have some kind of directory services. If we only had one mail system in an organization, we wouldn't need this session. Problem is, we're all struggling trying to maintain what we have now while either piloting or migrating to something new. The only way to achieve continuity in service in this state of flux is by developing a central naming standard and using directory services. This session describes one such naming standard and how that standard was implemented using Innosoft's PMDF product.
Unless we get all of our mail systems to use the same directory service, we are faced with maintenance of multiple directories with similar information. This session reviews the techniques used to synchronize DDS, PMDF, and MS Exchange directories in one particular company's environment.
[Title and abstract by Donald Borsay, Allendale Mutual Insurance
Dr. Stephen L. Arnold is an independent consultant with over 14 years
of networking experience on OpenVMS, UNIX, and IBM mainframe and
midrange systems. Steve specializes in internetworking, electronic
mail, and directory services.
Management has tasked you to develop organization-wide mail directory services with these characteristics:
Note: Since you are connected to the Internet, you can't use the
seductive but impractical "same software for every user"
Native Electronic Mail Addresses
Used for addressing mail within a message handling system
Example: My DECUServe mailbox:
Used for addressing mail between messaging handling systems
These depend on both the gateway and the user agent!
Directory synchronization is frequently used to hide gateway addresses
from mail users.
Canonical (Internet) Addresses
There is no universally-used directory for the Internet! Instead, we use names for mailboxes.
For my work mailbox:
When this convention is implemented across organizational units or mail
platforms, it is often called central naming. Names and the
corresponding Internet native or gateway mail addresses must be
gathered on a mail hub (or backbone), which is responsible for routing
Example Directory Environment
Using ALL-IN-1 and Digital's Distributed Directory Service (DDS), Microsoft Exchange, and an Internet connection; we would like to meet objectives with directory synchronization, maintaining:
Three mail communities could require six directory exchanges. We have four, because all Internet users cannot be loaded into our directories!
Each "directory exchange" has three steps:
How many exchanges are needed if we add Lotus Notes?
Directory Synchronization Tactics
For each directory source:
Note: Steps 1-3 represent an outer loop. Step 3 is an inner loop. This
problem gets bigger geometrically as we add mail systems!
PMDF Directory Tools
PMDF includes directory tools to manipulate the X.500 Directory (via LDAP), entry description files, and foreign directories:
Directories supported include:
To import ALL-IN-1 profile entries to an EDF file for exporting to another directory or loading into the X.500 Directory, enter, for example:
$ pmdf directory /import /a1 /rooting - /domain="Chicago.Acme.Com" /country=US - /org="Acme Corporation"
A sample entry description from ALL-IN-1:
RootedAt=o=Acme Corporation cn=Kelly B Forker mail=Kelly.B.Forker@Chi.Acme.Com postalAddress=Acme Corporation $ P.O. Box 1234 $ \ Chicago, IL 60001-1234 userClass=a1 uid=KFORKER sn=Forker l=Chicago roomNumber=14th Floor ms 52 phone=+1 312 814 2289 objectClass= top & quipuObject objectClass=organizationalPerson objectClass=organizationalUnit objectClass=person objectClass=newPilotPerson
The userClass attribute is automatically set up by the
directory tools. We use it to keep track of the authoritative sources
Terminology for this session:
Using ALL-IN-1 and DDS, Microsoft Exchange, and an Internet connection; we might instead meet objectives with a distributed (X.500) directory:
Three mail communities could require three X.500 loads. We only have two, because all Internet users cannot be loaded into our X.500 directory!
Each X.500 load has the same three steps required by a directory exchange.
Additional benefits from the X.500 approach:
Exercise: How many exchanges if we add Lotus Notes?
Distributed Directory Tactics
For each directory source:
Note: Steps 1-5 represent the only loop. There is no inner loop. This
problem gets bigger linearly as we add mail systems.
OSI Identifier Registration
To participate in X.500, obtain these identifiers from ANSI:
Total cost: $3000. Waiting time: 90-120 days.
Don't worry about challenges. There have never been any!
Smaller organizations may register in the Internet White Pages under their corporation name at no charge.
(The examples are hypothetical. Arnold
Consulting is a "smaller" organization, and not
registered with ANSI. Its entry in the Internet white pages
is under Wisconsin, its state of incorporation.)
For medium and large organizations:
Steve Arnold, Ph.D., President
2530 Targhee Street, Fitchburg, Wisconsin 53711-5491
Telephone: +1 608 278 7700
Facsimile: +1 608 278 7701
Back to the Arnold Consulting Welcome Page
This page was last updated 27 May 2013, and has been visited 17,975 times.