Network Support Library/RoseWare - Network Support Library.iso/mhs/mhs_40.txt

Text File | 1993-04-10 | 26KB | 527 lines

Introduction

Novell's NetWare MHS product family provides a messaging
infrastructure service.  With the introduction of NetWare 4.0, MHS
is able to provide a new level of service, particularly with
respect to directory support.

Because messaging is by nature a fully distributed service that is
used on a network-wide basis, the concept of a directory is very
important.  NetWare Global MHS is Novell's NLM-based messaging
product that includes messaging-specific directory support designed
to (1) service environments without NetWare 4.0, (2) integrate
NetWare 3.X messaging environments with NetWare 4.0, and (3)
propagate message routing information.  This approach allows
NetWare Global MHS to provide the complete messaging solution
required by customers and MHS application developers.
Directory integration of NetWare 3.X and NetWare 4.0 is made
possible because the NetWare Global MHS directory is structurally
identical to NetWare 4.0 directory service (NDS), permitting a
single, hierarchical name space to be visible to both NetWare 4.0
users and NetWare 3.X users.

NetWare MHS

NetWare MHS is a store-and-forward messaging technology that
provides messaging and directory services to any desktop that has
file access to a NetWare server (e.g. DOS, Windows, Macintosh,
Unix, and OS/2), and to disconnected laptops.
MHS is typically used in conjunction with messaging applications
such as e-mail, calendaring, and network fax.  Commercial third
party products include DaVinci's eMail and Coordinator, Beyond's
BeyondMail, Reach's MailMAN and WorkMAN, Powercore's WinMail,
Infinite's ExpressIT!, Notework's Notework, Futurus' Team,
MicroSystems Software's CaLANdar, Campbell Services' OnTime,
Castelle's FaxPress, Lantec's XPost, Optus' FACSys, CE Software's
QuickMail, Transend's CompletE-Mail, and many others (see the
NetWare Messaging Solutions Guide).  In addition, MHS comes with a
starter e-mail package, FirstMail, to enable the user to get
started with messaging.

Submitting a message to MHS is as easy as creating a text file with
appropriate headers and giving MHS access to the new file.  This
simplicity makes it easy for third parties to develop applications
and for system integrators and corporate developers to utilize the
messaging system.  For example, an e-mail message may look like
this:

smf-71
To: Bob Smith @ marketing . acme
From: Tim Johnson @ engineering . acme
Subject: Q1 Results?

Are the quarterly results in yet?


Once a message has been submitted, MHS takes the message and
determines how to route it through the messaging system.  MHS
implements various messaging protocols, including the standard MHS
protocols as well as other industry standards such as SMTP, SNADS,
and X.400.

After sending a message through the messaging system, MHS delivers
the message into a file that the recipient's application may
access.

In addition to the messaging service, MHS provides a directory
system for use by MHS and its applications.  An application gains
access to directory information by opening a shared file on the
NetWare server that contains information about which users are on
the messaging system.  E-mail applications typically use this
information to provide point-and-click lists to the users.
The naming scheme for MHS is hierarchical.  For example,


Bob Smith's MHS name is formed from this tree: BobSmith @ marketing
. acme.

The nodes in the naming tree that aren't leaf nodes are called
workgroups.  Thus Acme is a workgroup that contains two other
workgroups, marketing.acme, and engineering.acme.

This hierarchical naming scheme allows a single unique global name
for all MHS messaging users to ensure that no two MHS messaging
users in the world have the same MHS name.  In addition, this
naming scheme is structurally identical to NetWare 4.0 directory
services (NDS).

Applications can also gain access to the directory information.
They typically use this information to provide point-and-click
lists to the users.  MHS provides this information in the form of
an extract file.  The extract file contains sorted records in a
fixed length format.  Each record contains information about a user
of the messaging system, such as mail address, phone number, title,
department, etc.

The sharing of directory information between servers is
accomplished through a subscription mechanism.  This mechanism is
another characteristic of the NetWare Global MHS directory that
logically relates to NDS functionality.  By subscribing to a
"foreign" workgroup, the names of all users in this workgroup are
appended to the current workgroup and appear to be locally
accessible.

NetWare Global MHS

The NetWare Global MHS product provides scalable, fully integrated
MHS services to NetWare 3.X users.  A version of NetWare Global MHS
which is fully NetWare 4.0 "aware" will be released in Q3 '93.
Implemented as a set of NetWare Loadable Modules (NLMs) for NetWare
3.X and NetWare 4.0, NetWare Global MHS enables the network
operating system to support a complete messaging infrastructure.
This approach allows messaging services to be easily installed, and
capitalizes on existing NetWare investments. NetWare Global MHS
provides built-in directory support, routing,
workgroup-to-workgroup connectivity, and offers optional protocol
modules for messaging interoperability with users on SMTP, SNADS,
and X.400 systems.

In order to understand how Global MHS and NetWare 4.0 work
together, it is important to understand the directory
synchronization mechanisms implemented by Global MHS in the NetWare
3.X environment.

Users and their associated mailboxes can be added to a server in a
3.X environment through the administrative utility in Global MHS.
That server becomes the "owner" of that user object, and it
commands the right to modify or delete the object.  The fact that
this object exists is propagated by MHS to other MHS systems by
creating MHS directory synchronization messages.  In addition to
user information, distribution lists and workgroup information is
also propagated the same way.  To minimize synchronization traffic,
only changes in the directory are propagated immediately.  MHS will
also periodically (e.g. monthly) synchronize  the entire directory
to ensure that all servers have the same directory information
(this is useful to guard against undelivered directory
synchronization messages that may have resulted from servers being
down for a long period of time, or a loss of a communications
link). Global MHS also uses directory synchronization messages to
synchronize routing information, including which servers are
connected to each other and by what protocol.

Global MHS uses the user information in the directory for routing
purposes.  Routing in Global MHS is  a two-step process.  The first
step is to look up the recipient's name to determine on which
server the mailbox is.  The second step is to examine the
connectivity of the network to determine the best path to that
server.  Messages are then routed accordingly.

NetWare 4.0

NetWare 4.0 implements a variety of new services and functionality.
The feature that is particularly relevant to MHS is NetWare
Directory Services (NDS).  NDS implements a distributed directory
database that takes over the role performed by the bindery in
previous releases of NetWare.

NDS is very similar in model to the X.500 international standard
and to the NetWare Global MHS directory.  Names in the directory
are hierarchical:

This is very similar to the MHS naming scheme, with the exception
that NDS permits nodes in the directory tree to have a type
associated with them such as organization, or common name.  In the
example above, "org" is short for "organization", "ou" is short for
"organizational unit," and "cn" is short for "common name."  Note
that NDS specifies that use of these types is optional, and even
when used, typing is not normally visible to the user or to the
application.

API access to the NDS directory is very broad, providing read and
write access to a large number of objects, allowing for yellow-page
search operations, comparison of attributes, modification to the
schema of the directory and partition management. In addition to
information about users, the directory can contain information
about many other types of objectsAprinters, devices, queues, file
volumes, and more.  Since the schema is extensible, other types of
information can be added as well.

In order to facilitate management of the directory, NDS divides the
tree into logical divisions or partitions.  The partitions may not
overlap, and each node in the tree falls into a partition.


In the above example, the tree is divided into two partitions.
Information about each partition is kept in a file on a server.
The administrator determines where the "master copy" of the
partition data resides, and where replicas of each partition (if
any) are to be kept.  Making replicas of partitions increases the
reliability of the directory and can increase the performance of
the directory.  If a query to the directory is made and the
currently attached server does not have the information locally, it
will refer the requester to a server that does have the
information.  The effect of replicated partitions is very similar
to the Global MHS subscription mechanism.

MHS in a NetWare 4.0 Environment

Single Naming Scheme

Using NetWare Global MHS in a NetWare 4.0 environment provides the
administrator with a single unified view of the naming scheme.  A
user is given a name such as Joe [e-mail].  This single
name is used as a unique network identity for the user regardless
of the usageAnetwork login, file access control lists, point and
click lists in email applications, and other applications,
administrative programs and utilities.

Single Point of Administration

Using MHS in the NetWare 4.0 environment brings a new level of
integration between NetWare and MHS.  The standard administration
utilities that come with NetWare can be used to administer mail
accounts.  One of the attributes of the user object in NDS is used
to identify where the mailbox for that user resides.  When this
attribute is set, NDS notifies MHS, which takes care of the
administrative details such as setting up the user's account A
creating the necessary file directories, and, if appropriate,
updating the MHS routing tables, and notifying other MHS systems
that don't have access to NDS (more on this later).

In addition to the NetWare utilities for managing users,
workgroups, and distribution lists, MHS provides administrative
utilities for managing other aspects of the messaging system such
as configuring the messaging connectivity, management of the
messaging queues, viewing of messaging statistics and network
utilization, etc.

Remote Administration

NetWare 4.0 implements a network-wide view of services.  This
allows the entire network to be administered from the vantage point
of a single-user interface.  Global MHS capitalizes on this feature
to provide remote administration of the MHS messaging system.
Using the standard NetWare 4.0 utilities NETADMIN  (DOS version),
or NWADMIN (Windows version), an administrator can add users with
mailbox accounts on servers throughout the 4.0 network.  In
contrast, using Global MHS in the NetWare 3.X environment requires
the user to use, for example, RCONSOLE  to connect to each
messaging server to which a mailbox is to be added.

Directory Synchronization

Global MHS leverages the powerful directory services provided with
NetWare 4.0.  When a user is added to the NetWare 4.0 network, NDS
replicates that information as needed throughout the network,
relieving Global MHS from that responsibility.  In contrast, Global
MHS in the NetWare 3.X environment, by necessity, propagates
information about new users added to the system to other Global MHS
systems using directory synchronization messages.

On each system with Global MHS, NDS invokes MHS to perform the
necessary account administration and updates the MHS routing
database and extract file.

API Access

With MHS running on NetWare 4.0, all of the same interfaces that
are provided throughout the MHS product family are fully supported.
MHS provides SMF v70 and SMF v71 APIs, and maintains all of the
administrative interfaces common to the product lineAthe same "snd"
directory for submitting messages, the same extract file for
accessing the messaging directory, the same configuration files for
setting up auto-forwarding, etc.  An application written to support
Global MHS in the NetWare 3.X environment will continue to operate
in the 4.0 environment without any modification, and all messaging
relevant directory information is available using the file-based
extract mechanism. The administrator controls the contents of the
extract file by setting up local NDS replicas of the pieces of the
directory tree he desires to be accessible to his messaging users.
Future versions of SMF will also incorporate additional information
relevant to messaging services in order to satisfy ongoing
developer requirements and the evolution of NDS.

In addition to the usual access to the extract file, applications
can use the NDS APIs to get access to the directory information.
These APIs provide powerful interfaces for directory services,
including directory searches, modification to the directory schema,
and management of the directory partitions. Third-party developers
wishing to take advantage of these features will create
applications fine-tuned for the NetWare 4.0 environment, whereas
developers desiring to have a single product that will run across
the entire NetWare messaging product line will continue to use the
messaging directory interfaces.

Theory of Operation

The following diagram shows the components involved in the
messaging and directory system.

The system is administered from a workstation running standard
NetWare utilities.  When a new user is added to the network, NDS
notifies MHS.  Should the administrator wish to assign a mailbox
location for the user, the mailbox must be located on a server
where partition information containing the user, master or replica,
is stored.  When the mailbox is assigned, MHS will create the
actual mailbox and update the routing and extract files.  MHS will
also take care of updating other workgroup routing and extract
files through its normal synchronization process.

Global MHS also maintains synchronization of routing information.
Routing information is administered through Global MHS
administration utilities and is propagated through its own
directory synchronization messages, not through the NDS directory.

The routing process in MHS takes place in the usual Global MHS
fashion. For recipients in the local MHS routing database, the
final destination server is determined from the routing database,
and the connectivity is examined to determine the most efficient
route to that server.  For recipients in the local MHS domain, the
message is sent to the workgroup hub for further routing.  MHS
consults the configured information about foreign domains for
messages destined for external domains.

Global MHS in a Mixed NetWare 3.X and NetWare 4.0 Environment

Administrative Model

Global MHS fully supports environments of mixed NetWare 3.X and
NetWare 4.0 systems, each running MHS.  This is the most powerful
aspect of using MHS with NetWare 4.0.

The directories of Global MHS on NetWare 3.X and the NetWare 4.0
systems are unified, providing a single view of the naming
hierarchy.  All Global MHS users on 3.X systems also appear in the
directory on NetWare 4.0, and all NetWare 4.0 names in the local
Global MHS domain appear in the Global MHS directories on the 3.X
system.  A pick list of all the available users in the directory is
offered to an e-mail user on the 3.X system, regardless of whether
the recipient resides on a 3.X or 4.0 system. The same is true for
users on the 4.0 systemApick-lists of all the available recipients
are available, regardless of where that recipient resides.

On the 3.X systems, Global MHS is administered as usual.  Each of
the MHS servers on 4.0 systems looks exactly like the MHS systems
running on the NetWare 3.X systems. There is no additional
configuration or management needed on the 3.X systems to
accommodate the mixed model.

On the 4.0 systems, Global MHS is administered with the usual
network-centric administration model pioneered in NetWare 4.0.
Lastly, in a mixed environment, one of the NetWare 4.0 servers
running Global MHS must be designated as the directory
synchronization hub for the 3.X Global MHS directory and the
NetWare 4.0 directory.

Theory of Operation

A combination of the Global MHS directory synchronization
facilities and the NetWare 4.0 Directory Services makes the high
level of integration between 3.X and 4.0 systems possible.

The 3.X systems send all  information on their local users to all
other systems, both 3.X and 4.0, through Global MHS directory
synchronization messages.  The 4.0 systems send all information
about their local users to all 3.X systems through Global MHS
directory synchronization messages.  The 4.0 systems share
directory information with each other through 4.0 NDS.  In
addition, one of the 4.0 systems is designated to be the directory
synchronization hub that adds information about the 3.X Global MHS
names into the 4.0 system.  As in the homogeneous 4.0 environment,
the Global MHS routing database and extract file contain all the
4.0 messaging users that are contained in any local replica or
master copy of an NDS partition.  This information is combined with
the users information in the 3.X Global MHS environment.

Installation and Upgrade Features

MHS provides a number of installation and upgrade options to
facilitate the smooth installation and migration of network
operating system and messaging services.

When MHS is installed on a NetWare 4.0 system, the administrator
has the option of giving mailboxes to a set of NDS users.  This
eliminates the tedium of having to identify where the mailbox
resides for each individual NetWare 4.0 user.

More importantly, the procedure for upgrading from a NetWare 3.X
system that is running Global MHS to a NetWare 4.0 system with
Global MHS offers the option of building the NetWare 4.0 directory
from the existing hierarchical Global MHS directory.  This will
minimize the administrative effort and eliminate errors.

Summary

NetWare Global MHS provides a messaging infrastructure service for
NetWare 3.X users, NetWare 4.0 users and, most importantly, for
users of mixed networks.  It provides an integrated, unified
administrative environment as well as a uniform messaging
application platform.  This is primarily enabled by the
complementary directory services feature included in both the
NetWare Global MHS and the NetWare 4.0 products.

Questions and Answers

Q.  Is it possible to have directory conflicts between Global MHS
and NDS?

A.   Since there is a single unified directory, the only possible
conflict is of the same nature as might occur within NDS alone. It
is theoretically possible that two administrators could
accidentally add the same name into the directory, for example,
when two Bob Smiths start work in an organization at the same time
but at different locations. If the two records are created in
NetWare 4.0, NetWare will resolve the       conflicts based on the time
stamps of the operations.  Global MHS in the NetWare 3.X
environment deals with conflicts by sending an e-mail message to
the system administrator asking that he manually rename one of the
users.

Q.  How is NDS object typing supported by Global MHS?

A.   The typing of objects in the directory is not visible through
the Global MHS administrative utilities, APIs, and MHS-based
applications.  The typing information is not needed for messaging.

Q.  How do the administrative paradigms for Global MHS and NetWare
4.0 compare?

A.   NetWare 4.0 and Global MHS running on 4.0 have a common
paradigm since Global MHS administration in the NetWare 4.0
environment is integrated into the NetWare operating system.  The
NetWare 4.0 directory browsing and maintenance utilities are used
to administer a single identity for each user and distribution
list.  Additional messaging-specific utilities are provided to
administer messaging routing information, manage messaging queues,
view messaging statistics, logging, accounting information, and
other messaging specific functions.

Q.  When should an administrator use NETADMIN versus NetWare Global
MHS  administrative tools?

A.   The NetWare 4.0 utilities should be used to create and
administer users and distribution lists.  The NetWare Global MHS
administrative tools must be used for messaging-specific
information.

Q.  When should MHS developers use the NetWare 4.0 NDS APIs?

A.   It is expected that MHS developers will use the standard SMF
directory interfaces for access to directory information so that
applications will run uniformly in a mixed NetWare 3.X/4.0
environment.  The 4.0 NDS APIs would be used to access
non-messaging related objects such as network device information,
manipulation of the directory access control lists, management, and
to create NetWare 4.0 specific applications.

Q.  What is the relationship between Global MHS "subscriptions" and
NDS  "replicated partitions?"

A.   Global MHS running in the NetWare 3.X environment incorporates
the notion of subscription to control the information that is
replicated to a given server.  The administrator subscribes to the
workgroups he wants to show up in an MHS application's "point and
click" lists.  Similarly, portions of the NDS directory tree
(partitions) may be replicated in a controlled manner across
NetWare 4.0 systems. The administrator requests a local copy of a
partition to be replicated for the purpose of redundancy, efficient
access, and in the case of Global MHS, to provide the
point-and-click list to the messaging applications.

Q.  Where is the mailbox located when you create a user using
NETADMIN and its network wide view?

A.   In NetWare 4.0. a user is created as a "network" user.   One
of the attributes of a user indicates where the mailbox is located.

Q.  How are multiple addresses (users may have an MHS, X.400, or
SMTP address) for each user handled?

A.   The MHS address is the user's only NetWare identity.  However,
for messaging purposes, a given user may have additional mail
addresses viewed from a non-NetWare messaging system.  For example,
Bob may have a NetWare name of Bob@marketing. acme.  Users of MHS
systems would address messages to this name.  Bob could also have
an SMTP identity of [e-mail].  Users on systems using SMTP
could address Bob using this SMTP name.  All messages transparently
arrive in Bob's mailbox.  Similarly, a user who has a mailbox in a
non-MHS account can be given a NetWare identity.  Sally on a Unix
machine may have an SMTP address of [e-mail], but be given a
NetWare identity of [e-mail].  Users on an MHS system
can then send messages to Sally by simply supplying her MHS name.
This allows MHS users to send messages without having to know
whether the recipient's mailbox is in NetWare, Unix, PROFS, etc.

Q.  How does the upgrade from NetWare v3.11 to NetWare 4.0 work and
what is the process?

A.   NetWare 4.0 is installed on top of v3.11.  During the
installation, the administrator is given the option to incorporate
the 3.11 bindery into the NetWare 4.0 directory, placing all the
bindery users into a single directory container.  The administrator
will typically choose this option if he has      applications that
depend on the bindery information for proper operation.  Once the
NetWare operating system is up, Global MHS is upgraded with a
release supporting NetWare 4.0 (available in Q3 '93).  The upgrade
process allows the administrator to create NDS accounts using the
hierarchical name that MHS uses when running in the 3.11
environment.  If the administrator has already created user objects
for bindery emulation, MHS creates alias objects that point from
the hierarchical name to the flat bindery emulation name.

Q.  What additional benefits does NetWare 4.0 provide to NetWare
Global MHS?

A.   In addition to directory and administrative advantages of
running MHS on NetWare 4.0, MHS takes advantage of enhancements
included in NetWare 4.0 such as memory protection, improvements in
network security, data storage and wide area connectivity.  These
enhancements are provided to MHS through its NLM design.

Q.  How will interoperability with X.500 be provided?

A.   NetWare 4.0 and NetWare Global MHS directories were built with
X.500 in mind.  The hierarchical directories of NetWare map
directly to the hierarchical name space of X.500.

References

NetWare Global MHS Administration
SMF v71 Programmer's Reference
NetWare Directory Services Technical Reference
NetWare 4.0 Directory Services Schema Specification
NetWare 4.0 NLM Library Reference
NetWare 4.0 Supervising the NetWork
NetWare 4.0 Utilities Reference