HP 3000 Manuals HP 3000 Manuals
ARPA Header Format
HP Desk uses a subset of the ARPA Standard header with a number of
additions to suit HP Desk's special requirements. The table below shows
all the ARPA header fields currently recognized by HP Desk. Where
appropriate the information in an outgoing HP Desk message from which the
field contents are derived is shown.
HP Desk Information (Outgoing) ARPA Header Fields
Date : 11 Nov 91 1643 GMT
Date : 11 Nov 91 1643 +0000
Sender : Jean JONES / EM/00 Sender : "Jean JONES"@[EM/00.EMBERTAL]
From : From :
To : Colin DRAPER(ABC212) / TALON To : "Colin DRAPER"@[ABC212],
Sue LANGFORD(ABC212) / TALON "Sue LANGFORD"@[ABC212]
CC : Bob WILSON(ABC212) / TALON CC : "Bob WILSON"@[ABC212]
BCC : Alan MANAGER(XYZ878) / TALON BCC : "Alan MANAGER"@[XYZ878]
Subject : A sample ARPA format message Subject : A sample ARPA format message
Message identity information X-HPDESK-ID :3629362 12345 4567 4 "TALON"
URGENT : X-HPDESK- :2
PRIORITY
HP Desk will accept any ARPA header field constructed in accordance with
the ARPA standards. However, if on an incoming message the HP Desk
parser finds a complicated or lengthy ARPA element which is not fully
supported by HP Desk , only the most significant parts of it will be
transcribed into HP Desk.
In the example:
* The Sender exists on an HP Desk network and has the mailnode
address EM/00.
* The addresses exist on a foreign network known to HP Desk as
"TALON". Their own network addresses are combinations of
alphabetic and numeric characters. The HP Desk network does not
know what these addresses mean, they can only be resolved by the
foreign network.
* The message is passed to the foreign network through a gateway
with the Gateway Reference Name "EMBERTAL".
If the foreign network accepts and generates headers in ARPA format, it
will only be necessary to advise the administrator of the foreign system
of the format and use of the user-defined fields X-HPDESK-ID,
X-HPDESK-ACK and X-HPDESK-PRIORITY.
NOTE An "X-HPDESK-SYSTEM" item exists in outgoing messages. It is used
to communicate with standard HP Desk FSC packages. The foreign
system may be unable to use those fields and in that case will
ignore them.
If the foreign network uses a format other than ARPA to communicate with
the HP Desk network, translation between the ARPA format used by HP Desk
and the format used by the foreign system is necessary. This translation
must be carried out by an external application program and you should
note the points in the following section.
ARPA Header Field Formats
The following general rules apply to the header fields:
* A header line on which a field begins must start with a printable
character other than a colon.
* A header line which continues a field must begin with an ASCII
space or HTAB character.
* If an addressee field (TO, CC or BCC) contains multiple names,
each name other than the last in that field must terminate with a
comma, CRLF and ASCII space(s).
* A header line on which a simple field ends or, in the case of a
field containing multiple names and addresses, the line on which
the last entry of the field ends, must end with a CRLF.
The ARPA header field definitions given below are those used by HP Desk
for the headers of outgoing messages. Foreign system formats may have
longer, more complex elements in their equivalent fields. If the
elements as specified for HP Desk cannot be identified precisely by
parsing, the element should be placed in the field intact. The HP Desk
mechanism will truncate the element as required. The following
conventions are used in the field definitions:
<LWSP> means linear white space, that is ASCII spaces or
CRLF followed by ASCII space(s). Optionally ASCII
space(s) may precede the CRLF as well as follow it.
" " Characters or words enclosed in quotes must be
reproduced exactly as shown.
""" This is a required quote.
[ ] Anything enclosed in square brackets is optional
and does not have to be included
Date Field
This field is supplied automatically by HP Desk on both incoming and
outgoing messages, therefore, it need not be supplied in incoming
messages and only need be translated in outgoing messages if the foreign
system requires this. Any date in the incoming ARPA header is ignored.
The format used by HP Desk in outgoing messages, and automatically
imposed on incoming messages, is:
"Date"<LWSP>":"<LWSP>dd<LWSP>Mmm<LWSP>yy<LWSP>hh":"mm<LWSP>"+"/"-"<LWSP>nnnn
where:
dd is the day of the month (one or two digits)
Mmm is the month of the year denoted by its first three
letters. The first letter is a capital.
yy is the year
hhmm is the local time in 24 hour format at which the
message was mailed. This time is shown as offset
from GMT by nnnn.
nnnn is the amount by which local time is plus or minus
GMT.
Example:
Date : 11 Nov 91 17:31 +0000
Name/Address Fields
The Sender, From, To, CC and BCC fields have the following general form:
<LWSP>":"<LWSP>"""[<firstname>]<LWSP>[<secondname>]<LWSP><LASTNAME>""" "@[";[<ownnetadd>] [<.gatewayref>]"]"
<ownnetadd>
This always appears in the Sender field of an outgoing (HP Desk to
foreign) message. It also appears in the recipient fields of the ARPA
header of outgoing messages and may be an explicit address, an alias or
(as a last resort) the HP Desk mailnode.
<gatewayref>
If a Gateway Reference Name has been configured in HP Desk for the
gateway to the foreign system, it is concatenated with the HP Desk
location address (<ownnetadd>) of the sender of an outgoing message.
Sender Field
This is always present in both outgoing and incoming headers. The name
and address in this field are those of the person who mailed the message.
When a designate sends on behalf of a principal, it is the designate who
appears as the sender. There is also an optional part that can be added
to the Sender address. It corresponds to the Foreign System Gateway
reference name that can be configured for each gateway on your computer.
This name is used to identify your machine to other networks and should
always begin with a period (.). The name will be automatically appended
to the Sender address so that a foreign network knows exactly how to
reply to the message. Some systems may convert the period into some
other separator character.
From Field
This is not completed by HP Desk on outgoing messages originating from HP
Desk but is accepted on incoming ones. Incoming message headers should
be parsed for the information, which should be written to this field if
found. The name and address here are those of the person who originated
the message. If this field is present in the ARPA header, the FSC truck
will add the "From name" to the Distribution List and HP Desk will
attempt to deliver a copy of the message to that name. This could result
in a message being passed out of HP Desk to the foreign system again.
To, CC and BCC Fields
If there are one or more names in the given category of addressee, these
fields are always completed for both outgoing and incoming messages.
There must always be at least one To addressee. Only addressees on the
HP Desk node configured for the foreign network appear in the ARPA header
of an outgoing HP Desk message. In the example above, all addressees
reside on "TALON". Conversely, the Distribution List of an incoming
message should be parsed to identify only those addressees on the HP Desk
network, otherwise the system will attempt to deliver to all the names.
Subject Field
Used by HP Desk for both outgoing and incoming messages. The format of
this field is:
"Subject" <LWSP> ":" <subject as in HP Desk message>
X-HPDESK-ID Field
This is used only for messages leaving HP Desk. It is a message
identifying string which contains information that can be used by foreign
networks to generate acknowledgments for the message should they be
required. The field contains the item number of the message, the item
number of the sender's Pending Tray, the user number of the sender,the HP
Desk address of the foreign system, the acknowledgment level requested (0
to 6), and the address used to process each instance of the message.
Acknowledgment requested. Since HP Desk does not currently recognize
foreign message identification and is unable to provide automatic
acknowledgment of incoming foreign messages, it is not necessary to
supply incoming headers for this information.
NOTE HP Desk cannot acknowledge a message originating in the foreign
system.
X-HPDESK-ID has the definition:
"X-HPDESK-ID"<LWSP>":"<LWSP><double><LWSP><double><LWSP><double><LWSP><ACK level><LWSP><HP DESK identifier for foreign system>
* <double> represents a one or two-word number which may therefore
comprise up to ten decimal digits. HP Desk inserts numbers in
each of these elements; together, these three numbers uniquely
identify the message so that, on return of the ACK, HP Desk can
determine which item was acknowledged.
* <ACK level> the number in this denotes the acknowledgment
requested from the foreign system and has the same meaning as in
the HP Desk user interface when an acknowledgment is put on a
message:
0 = Ignore this field. It allows the field to be given to a
foreign system, whether or not the foreign system has an
acknowledgment capability.
1 = Transmitted. This is redundant since the level 1
acknowledgment is generated within HP Desk as soon as the message
is placed on the node queue. This will not appear in a message
destined for a foreign system.
2 = Received. This should be used to mean that the relevant
message has reached the destination foreign system.
3 = Delivered. The message has reached the addressee's In Tray or
foreign equivalent. The Sender field of the acknowledgment
message identifies whose In Tray equivalent the message has
reached.
4 = Read. The addressee has read the message. The Sender field
identifies the addressee who has read it.
5 = Reply. The acknowledgment message is a reply from the
recipient.
_________________________________________________________________
NOTE For acknowledgment levels from 1 to 4 inclusive, the
information content of the message is disregarded. Level 2
requests just one acknowledgment from the foreign system for
the message; levels 3 to 5 each request an acknowledgment
from each addressee of the message.
_________________________________________________________________
* <HP Desk identifier for foreign system> is the address which
follows the addressee's name (and foreign address if given) in the
original distribution. This is "TALON" in the previous example.
X-HPDESK-PRIORITY Field
This shows the original HP Desk priority level of an outgoing message for
foreign systems to take account of if they are capable of doing so. It
is always present in an outgoing message. A "2" in this field denotes an
urgent priority, and a 3 denotes normal priority. HP Desk does not
currently recognize the priority level of an incoming message from a
foreign system, therefore there is no need to parse the header of an
incoming message for this information. It has the definition:
"X-HPDESK-PRIORITY" <LWSP> ":" <LWSP><Priority level>
The number in <Priority level> has the following meaning:
1 = (for future use)
2 = Urgent
3 = Normal
4 = Deferred (not applicable)
X-HPDESK-ACK Field
This field is derived from the X-HPDESK-ID field, and has the same
format, so that it contains enough information to generate an
acknowledgment against the original message. However, whereas the
acknowledgment level in the X-HPDESK-ID field represents the requested
acknowledgment level, the same item in the X-HPDESK-ACK field represents
the level of acknowledgment being returned by this message. It normally
only appears on incoming acknowledgments returned by the foreign system
in response to previous messages. If this field is found in the ARPA
header, then HP Desk will handle the message as it would a normal
acknowledgment. Consequently the corresponding foreign format field of
an incoming message must be parsed to complete this field. In some
situations the field is generated on replies exported from HP Desk if the
REPLY command has been used within the user interface.
This is the item that a foreign system should return in order to satisfy
an acknowledgment request set on a message for an HP Desk system. It
will also sometimes be generated on messages leaving HP Desk if the REPLY
command is used in the user interface.
Apart from the <field header> the format of this field conforms to that
of X-HPDESK-ID. The foreign system substitutes in the <ACK level>
element the actual acknowledgment level being given. The digit entered
has the meaning defined under X-HPDESK-ID.
X-HPDESK-PRIVATE Field
If a message has been marked as PRIVATE, and the FSC gateway has been
configured to allow the passage of private messages, then this will be
indicated by the presence of this field in the ARPA header. If a private
message appears in the In Tray of the Default User, only the Distribution
List can be read, so that the administrator can forward the message to
the correct user.
X-HPDESK-APPT Field
This can be used by a foreign system to create an HP Desk message with an
appointment request set on it. HP Desk messages will have this item in
the ARPA equivalent. It has the layout:
"X-HPDESK-APPT"<LWSP>":"<LWSP>dd<LWSP>Mmm<LWSP>yy<LWSP>hh<LWSP>":"<LWSP>mm","<LWSP>HH<LWSP>MM
where:
dd is the day of the month,
Mmm is the first three letters of the month,
yy is the year of the start of the appointment; and
hhmm is the local time in 24 hour format at which the
message was mailed.
HH:MM is the duration of the appointment in hours and
minutes.
If any of the items in the field are invalid in an incoming message, then
no appointment will be set. If the foreign system does not recognize or
action the appointment request, then the HP Desk sender will not be
notified.
Distribution Lists
HP Desk Distribution Lists in Foreign Systems..
FSC trucks can recognize and process an HP Desk Distribution List
specified by a foreign system in the ARPA header of a message. The named
Distribution List must be held in the List Area or Public Distribution
Lists folder of the Default User on the incoming FSC gateway. The name
of the list must be preceded by a colon within the quotes, but in all
other respects the format will be as for an ordinary To, CC or BCC entry.
For example:
To : ":MANAGERS" @ []
This indicates that the message is intended for all the names that appear
in an HP Desk Distribution List known as "MANAGERS" Since the individual
addresses are contained within the list, no address is required in the
ARPA header, this field should be empty as shown. At the gateway HP Desk
installation the specified Distribution List name will be compared with
all lists in the List Area of the Default User and then with all public
lists. If a single occurrence of the named list is found, all the names
in that list will be added to the To category of addressees for the
message. This will be done regardless of the categories of the
individual names in the list.
If the named list cannot be found, or if more than one list of that name
is found, a single copy of the message will be delivered to the Default
User.
The names and contents of HP Desk Distribution List to be used by foreign
systems must be agreed between the HP Desk gateway system manager and his
counterpart on the foreign system.
Distribution Lists in Incoming Messages..
A user on the foreign system may transmit one or more full Distribution
Lists to the HP Desk network with the intention that it be used for the
addressing of messages to the foreign system. This Distribution List
must be stored in the receiving users Listarea before this can happen.
Up to that point, the list is just a part of the message content.
Any such list must be made available to the FSC truck as an MPE file with
the complete Distribution List transcribed to ARPA format. The MPE file
code of this file must be 1169. The FSC truck will then convert the file
to HP Desk Distribution List format (MPE file code 1166) to be readable
and usable by the HP Desk user.
This conversion will be the best that the truck can achieve with the
given information, it will often involve some assumptions about
addresses.
If the address returned by the parser has the form of an HP Desk node,
the address will be reproduced as given, for example:
Chuck WILLIAMS @ [AAAAAA/99]
will be translated to:
Chuck WILLIAMS / AAAAAA/99
The address does not have to be recognized as an existing one.
If the address does not look like an HP Desk address, for example, it is
too long, starts with numeric characters or contains illegal characters,
it will be treated as a foreign address. That address will be shown in
braces after the name and the mail node of the Default User will follow.
For example:
Pam COTTER (123456@CASHEW) / AAAAAA/99
If a full Distribution List is the only addressing information provided
for the current message, the application program must extract the HP Desk
addressee information and form an ARPA header in addition to converting
the complete list to an MPE file type 1169.
Generating Acknowledgments.
HP Desk to FSC will maintain all ack levels except TRANSMITTED assuming
the foreign mail system can generate the necessary format files for input
to HP Desk. TRANSMITTED can be assumed as soon as the nodefile is built.
The information necessary for it to do this is contained in the
X-HPDESK-ID section of the ARPA header for the message and the
X-HPDESK-ACK field of the new message.
HP Desk allows outgoing FSC messages to be acknowledged, because all of
the required information to satisfy acknowledgments is contained in the
message. However, messages initiated by foreign systems cannot be
acknowledged by HP Desk.
If a meaningful acknowledgment is to be received by HP Desk, certain
information must be returned in the acknowledgment message. This
information is contained partly in the Distribution List and partly in
the X-HPDESK-ID field of the original message. This information must be
rearranged in ARPA format to form the acknowledgment message. The
rearrangement required is shown below:
Content of header message Items required in acknowledgment
Date : Nov 11, 1991
Sender : "SENDER"@[HP1600/00] Sender : "ADDRESSEEn" @ [ABC212]
From : "Originator"@[ABC212]
To : "ADDRESSEE1"@[ABC212], To : "SENDER" @ [ACCTS/01]
"ADDRESSEE2"@[DEF323]
CC : "ADDRESSEE3"@[ABC212]
BCC : "ADDRESSEE4"@[XYZ989]
X-HPDESK-ID : 123456 2345 4567 4 "TALON" X-HPDESK-ACK : 123456 2345 4567 4 "TALON"
ADDRESSEEn is the specific addressee who, according to the
acknowledgment, has read the original message. The Sender of the
original message becomes the addressee for each acknowledgment of the
message. The X-HPDESK-ACK field in the ARPA header contains the same
information as the X-HPDESK-ID field except that the acknowledgment level
will be that which is now being given not the highest level requested.