HP 3000 Manuals HP 3000 Manuals
Mail in a System with Gateways
A gateway is a means of allowing mail to leave HP Desk. HP Desk regards
a gateway as a virtual computer. At a gateway, mail--instead of being
passed to another computer--is stored in an MPE file. Another
application program must then organize further transport of this file
from the HP 3000.
A gateway can be one of the following types:
External File EFT gateways allow mail to be passed from one HP
Transfer Desk installation to another by a means other than
NS/3000 or DS/3000 data communication software.
Typically, this could be by the physical transport
of a magnetic tape--used as a backup to an
unreliable datacomm link, or to transfer mail to
another communications system.
Foreign Service FSC gateways allow mail to leave HP Desk and be
Connection passed to another application. Thus mail can be
exchanged with other, foreign, messaging systems,
such as IBM's Professional Office System (PROFS).
Alternatively, the external application could
process the messages passed to it in some other
way. This is achieved by transporting files in a
standard format, known as ARPA format. This format
defines a standard header that is appended to the
HP Desk message.
Intrinsically These gateways are available to connect to other
Accessible Gateway products such as HP Office Connect to X.400, SNADS,
HP OpenMail and HP OfficeFax. Also, if you have HP
DeskManagerPLUS, you can use the HP Desk Intrinsics
to write applications that connect with HP Desk.
Foreign Addressing
Foreign messaging systems that can be connected to HP Desk via FSC
gateways will have different methods of addressing mail. For example, a
message sent by one user of IBM's PROFS system to another is addressed to
computername(username)--very different from an HP Desk mail address.
This is to find its intended recipients on the foreign system, it must be
re-addressed in that system's form. Similarly, if HP Desk users are to
receive a message from a foreign system, the addresses of the message
must be converted from the foreign system's form into HP Desk mail
addresses.
HP Desk provides three methods of supplying a foreign address:
* A user supplies a foreign address together with the HP Desk mail
address when creating the Distribution List. Both addresses are
carried with the message. Within HP Desk the HP Desk mail address
is used; at the FSC gateway the foreign address is placed in the
ARPA header and sent out of HP Desk with the message.
* The Administrator configures a foreign address for a user, on the
local computer. Then the sender of a message has only to supply
the HP Desk mail address - HP Desk picks up the foreign address
from the Global Database on the local computer - and the message
progresses to the gateway computer as described above.
* The Administrator on the gateway computer configures foreign
address aliases for the foreign users.
A foreign address alias provides a user with two addresses:
* An HP Desk mail address.
* A foreign address.
HP Desk routes messages to users from both HP Desk and a foreign system
using the foreign address alias. Aliases allow for the foreign address
of the user and their related HP Desk address to be mapped together.
This address conversion thus facilitates communication between HP Desk
and other systems.
Using foreign address aliases ensures that mail passes easily from one
mailing system to another.
The Directory of the computer where the gateway resides contains names
for all users in both forms - HP Desk mail address and foreign form.
When an outgoing HP Desk message reaches the gateway computer, the Master
Truck reads the Directory in the Global Database and replaces the HP Desk
mail address with the registered foreign name.
EFT Gateways
At an EFT gateway, the Master Truck places outgoing messages in an MPE
file. This file is in a format that can only be read by another HP Desk
system. A record is written to an IPC file, which holds details of the
mail. An IPC file is a special type of MPE file that describes the
identity and destination of one or more MPE files. You must write an
application program to transfer the message file to the medium allocated
to EFT for HP Desk messages to the particular destination.
You must write another application program to receive the file at the
remote HP Desk installation. This program will pass on the file to the
EFT Truck which performs, for messages received through an EFT gateway, a
similar function to the Slave Truck. The EFT Truck converts the contents
of the file back into HP Desk messages, which are then passed to the
Mailroom or Transport Manager in the normal way.
FSC Gateways
An FSC gateway works in a similar way to an EFT gateway. The Master
Truck places outgoing messages in an MPE file, which is transported to a
remote computer under the supervision of an external, user-written
application program. Hewlett-Packard can supply some application
programs of this type, one example being HP OfficeConnect to PROFS.
Since mail passed through an FSC gateway is not destined for an HP Desk
system, the file of messages is created in one of a number of standard
formats. Messages in these formats can either be understood by the
remote computer directly, or be converted to a suitable format by an
application program on the gateway HP Desk system or the foreign
computer. In addition, the text of the messages may need to be converted
to a format suitable for the foreign system. For example, the text of
mail destined for IBM's DISOSS office system would have to be converted
into IBM's DCA document format.
Conversely, foreign systems can generate files containing messages in
formats acceptable to HP Desk. Other application programs can transport
those files to an HP 3000 running HP Desk and, if necessary, convert them
into the format used by HP Desk. There, they will be picked up by the
FSC Truck, which passes them to the Mailroom or Transport Manager in the
normal way.
HP Desk Intrinsics
An alternative is available which provides an improved way for HP Desk
and your applications to communicate. The HP Desk Intrinsics allow your
applications to access the mailing and other services of HP Desk by
letting them sign on to HP Desk in one of two ways:
* As an HP Desk user (allowing the sending and receiving of messages
on behalf of that user through HP Desk).
* To an HP Desk gateway (allowing the sending and receiving of
messages on behalf of any user associated with that gateway). By
signing on to a gateway your application can connect to other
mailing systems.
A separate manual is available on the Intrinsics, HP DeskManager
Intrinsics.
NOTE The HP Desk Intrinsics product is only available with HP
DeskManagerPLUS.