One document matched: draft-ietf-fax-implementers-guide-02.txt

Differences from draft-ietf-fax-implementers-guide-01.txt


IETF Fax Working Group                                             Vivian Cancio
Internet Draft                                                 Xerox Corporation
Category: Work-in-progress                                         Mike Moldovan
Intended Category: Informational                         G3Nova Technology, Inc.
                                                                  Hiroshi Tamura
                                                             Ricoh Company, LTD.
                                                        
 
                                                                    14 July 2000
                                                           Expires: January 2001


         Implementers Guide for Facsimile Using Internet Mail
             <draft-ietf-fax-implementers-guide-02.txt>


Status of this memo

  This document is an Internet-Draft and is in full conformance with
  all provisions of Section 10 of RFC 2026.

  Internet-Drafts are working documents of the Internet Engineering
  Task Force (IETF), its areas, and its working groups.  Note that
  other groups may also distribute working documents as Internet-
  Drafts.

  Internet-Drafts are draft documents valid for a maximum of six
  months and may be updated, replaced, or obsoleted by other
  documents at any time.  It is inappropriate to use Internet- Drafts
  as reference material or to cite them other than as "work in
  progress."


  The list of current Internet-Drafts can be accessed at
  http://www.ietf.org/ietf/1id-abstracts.txt

  The list of Internet-Draft Shadow Directories can be accessed at
  http://www.ietf.org/shadow.html.

 
  [[INTENDED STATUS: This memo provides information for the Internet
  community.  It does not specify an Internet standard of any kind.
  Distribution of this memo is unlimited.]]

Copyright Notice

  Copyright (C) The Internet Society 1999.  All Rights Reserved.

Abstract

This document is intended for the implementers of software which uses email to 
send to facsimiles using RFC 2305 and 2532.
This is an informational document and its guidelines do not supersede the  
referenced documents. 
  

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Table of contents

  1. Introduction     
     1.1 Organization of this document
     1.2 Convention of this document                         
     1.3 Discussion of this document                           
  2. Terminology 
  3. Implementation Issues Specific to Simple Mode 
     3.1 Simple Mode Fax Senders
       3.1.1 Multipart-alternative                               
     3.2 Simple Mode Fax Receivers
       3.2.1 Multipart-alternative and Storage Capacity
  4. Implementation Issues Specific to Extended Mode
     4.1 Multipart-alternative 
     4.2 Correlation of MDN with Original Message 
     4.3 Correlation of DSN with Original Message 
     4.4 Extended Mode Receivers
       4.4.1 Confirmation of receipt and processing from UA Clients
           4.4.1.1 Discrepancies in MDN [9] Interpretation
           4.4.1.2 Disposition-Type: "dispatched"
           4.4.1.3 "Subject" of MDN in Success and Failure Cases 
           4.4.1.4 "Body" of MDN in Success and Failure Cases 
       4.4.2 Extended Mode Receivers that are MTAs (or ESMTP servers)
           4.4.2.1 Success Case Example
           4.4.2.2 Failure Case Example 1
           4.4.2.3 Failure Case Example 2
       4.4.3 Extended Mode Receivers that are POP3/IMAP4 
           4.4.3.1 Success Case Example
           4.4.3.2 Failure Case Example
       4.4.4 Receiving Multiple TIFF-FX Attachments 
    5. Implementation Issues the File Format
     5.1 IFD Placement in TIFF file & Profile-S Constraints
     5.2 Precautions for implementers of RFC 2301 [4] 
       5.2.1 TIFF Readers: Be Cautious with Headers
       5.2.2 TIFF Writers: Be Cautious in use of IFD 
       5.2.3 IFD Entry Errors
       5.2.4 Strip Errors
       5.2.5 Image Errors
       5.2.6 Profile Specific Errors
  6. Security considerations 
  7. Acknowledgements  
  8. References 
  9. Authors' addresses 
  Full copyright statement 
  Revision history 









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1. Introduction

This document clarifies published RFCs which standardize facsimile 
communications using Internet Email. The intent is to prevent implementations 
that deviate in such a way as to cause interoperability problems. 
 

1.1 Organization of this document

See Section 2 for terminology.

   a) Simple mode clarifications
   b) Extended mode clarifications
   c) File format clarifications
   d) Fax Addressing Clarifications
   e) Open implementation issues

1.2. Convention of this document

[[[Editorial comments from authors are embedded in triple brackets
and will be removed before publication]]]

1.3 Discussion of this document

  Discussion of this document should take place on the Internet fax
  mailing list hosted by the Internet Mail Consortium (IMC).  Please
  send comments regarding this document to:

      ietf-fax@imc.org

  To subscribe to this list, send a message with the body 'subscribe'
  to "ietf-fax-request@imc.org".

  To see what has gone on before you subscribed, please see the
  mailing list archive at:

      http://www.imc.org/ietf-fax/

 
2. Terminology

Simple Mode   - RFC 2305, "A Simple Mode of Facsimile Using Internet Mail" [2]
Extended Mode - RFC 2532, "Extended Facsimile Using Internet Mail" [3]
TIFF-FX       - RFC 2301, "File Format for Internet Fax" [4]
UA            - User Agent
DSN           - Delivery Status Notification [7]
MDN           - Message Disposition Notification [9]
In examples:  - "C:" is used to indicates lines sent by the client, and
                "S:" to indicate those sent by the server.
MTA           - Message Transfer Agent



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3. Implementation Issues Specific to Simple Mode

3.1 Simple Mode Fax Senders

3.1.1 Multipart/alternative

Although a requirement of MIME compliance (see RFC 2046, Section 5.1.4), some 
email client implementations are not capable of correctly processing messages 
with a MIME Content-Type of "multipart/alternative". If a sender is unsure if 
the recipient is able to correctly process a message with a Content-Type of 
"multipart/alternative", the sender should assume the worst and not use this 
MIME Content-Type.


3.2 Simple Mode Fax Receivers

3.2.1 Multipart/alternative and Storage Capacity

Devices with little storage capacity are unable to cache previous parts of a 
multipart/alternative message.  In order for such devices to correctly process 
only one part of a multipart/alternative message, such devices may simply use 
the first process-able part of a multipart/alternative message. This is viable 
because the parts within a multipart/alternative are always sent in least-
fidelity to most-fidelity order. 

This behavior means that even if subsequent, higher-fidelity parts may have been 
process-able they will not be used.  

This behavior can cause user dissatisfaction because when two high-fidelity 
but low-memory devices are used with each other, the lowest-fidelity part of 
the multipart/alternative will be processed.

The solution to this problem is for the sender to determine the capability of 
the recipient and send only high fidelity. However a mechanism to determine the 
recipient capabilities priorto an initial message sent to the recipient doesn't 
yet exist on the Internet.

After an initial message is sent, the Extended Mode mechanism described in RFC 
2532 [3], Section 3.3 enables a recipient to include its capabilities in a 
delivery and/or a disposition notification:  in a DSN if the recipient device is 
an RFC 2532/ESMTP [3] compliant server or in an MDN if the recipient is only an 
UA. 











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4. Implementation Issues Specific to Extended Mode

4.1 Multipart/Alternative

     Sections 3.1.1 and 3.2.1 are also applicable to this mode.

4.2. Correlation of MDN with Original Message

     To re-iterate a paragraph from section 2.1, RFC 2298 [9], it is
     included here:

	A message that contains a Disposition-Notification-To header SHOULD
      also contain a Message-ID header as specified in RFC 822 [10]. This 
      will permit automatic correlation of MDNs with original messages by
      user agents.

4.3 Correlation of DSN with Original Message

Similar to the requirement to correlate an MDN, above, DSNs also need to be 
correlated. This is best done using the ENVID parameter in the "MAIL" 
command. See Sections 3 and 5.4 of RFC 1891 [5] for details.


4.4 Extended Mode Receivers

Confirmation that the facsimile image (TIFF-FX attachment) was delivered and 
successfully processed is an important aspect of the extended mode of facsimile 
using Internet mail.

4.4.1 Confirmation of receipt and processing from UA Clients

When a message is received with the "Disposition-Notification-To" header and the 
receiver has determined if the message is process-able, it may generate a:

a) Negative MDN in case of error, or
b) Positive MDN if requested by the sender.
 
The advantage of receiving a requested MDN acknowledgement from an Extended Mode 
recipient is the indication of success or failure to process the TIFF-FX file 
attachment that was sent. The attachment constitutes the facsimile message and 
not the body-content of the message. Therefore an Extended Mode sender would 
expect, and it is recommended that the Extended Mode receiver will acknowledge 
(with an MDN) the success or failure to decode and process the TIFF file 
attachment.

Implementers of the Extended Mode [3] should provide consistency in the feedback 
provided to senders in the form of error codes and/or failure/successful 
messages.





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4.4.1.1 Discrepancies in MDN [9] Interpretation

An Extended Mode sender must be aware that RFC 2298 [9] does not make a 
distinction between the success or failure to decode the body-content part of 
the message, from the success or failure to decode a file attachment. 
Consequently MDNs may be received which do not reflect the success or failure to 
decode the attached TIFF-FX file, but rather to decode the body-content part of 
the message.


4.4.1.2 Disposition-Type: "dispatched".

The receiver of an MDN request, if it is also an a RFC 2532 compliant device 
that automatically prints the received Internet mail messages and attachments, 
or forwards the attachment via GSTN fax, should respond with a "disposition-
type: dispatched" when the received message is successfully processed. This 
recommendation adheres to the definition in RFC 2298 [9] and helps to 
distinguish the returned MDNs for proper handling.

4.4.1.3 "Subject" of MDN in Success and Failure Cases

Because legacy e-mail applications do not parse the machine-readable headers, e-
mail users depend on the human-readable parts of the MDN to recognize the type 
of acknowledgement that is received. For the sake of consistency and to help 
users visually distinguish a DSN from an MDN returned notification, it is 
suggested that the text 'disposition' be used for MDNs in the 'Subject' field.
Example:
   Subject: Disposition Notification (MDN) - Successful  or
   Subject: Disposition Notification (MDN) û Failure

4.4.1.4 "Body" of MDN in Success and Failure Cases

If the receiver of an MDN request is also an RFC 2532 [3] compliant device that 
automatically prints the received Internet mail messages and attachments, or 
forwards the attachment via GSTN fax, for consistency the following text is 
suggested for the body of the message.

In case of success:

"This is a Return Receipt for the mail that you sent to [above, or below, or 
here address, etc]. The message and attached file[s] may have been printed, 
faxed or saved. This is no guarantee that the message has been read or 
understood".

In case if failure:

"This is a Return Receipt for the mail that you sent to [above, or below, or 
here address, etc]. An error occurred while attempting to decode the attached 
file[s].

[[[Include details on error; and maybe recognize language (of sender) in headers 
to send above text in appropriate language. From D.W.]]]

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4.4.2 Extended Mode Receivers that are MTAs (or ESMTP servers)

It is strongly encouraged that SMTP server-based implementations should 
implement "SMTP Service Extension for Returning Enhanced Error Codes" [6]. This 
standard is easy to implement and it allows detailed standardized success and 
error indications to be returned to the sender by the submitting MTA.
 
The following examples are provided as illustration only. They should not be 
interpreted as limiting the protocol or the DSN form. If the examples conflict 
with the definitions in the standards (RFC 1891/1893/1894/2034), the standards 
take precedence and the examples in this documents should not be used. 


4.4.2.1 Success Case Example

In the following example the sender <jean@water.line.com> sends a message to 
receiver <ifax@copper.point.com> which is an ESMTP server and the receiver 
successfully decodes the message.

SMTP Sequence:

   S: 220 copper.point.com SMTP service ready
   C: EHLO water.line.com
   S: 250-copper.point.com
   S: 250-DSN
   S: 250 ENHANCEDSTATUSCODES
   C: MAIL FROM:<jean@water.line.com> RET=HDRS ENVID=MM123456
   S: 250 2.1.0 Originator <jean@water.line.com> ok
   C: RCPT TO:<ifax@copper.point.com> NOTIFY=SUCCESS,FAILURE ORCPT=rfc822;
      ifax@copper.point.com
   S: 250 2.1.5 Recipient <ifax@copper.point.com> ok
   C: DATA
   S: 354 Send message, ending in <CRLF>.<CRLF>
    ...
    ...[[[Replace 'dots' with actual data. From D.W.]]]
    ...
    ...
   S: 250 2.0.0 Message accepted
   C: QUIT
   S: 221 2.0.0 Goodbye













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DSN (to jean@water.line.com):

   Date: Mon, 12 Dec 1999 19:01:57 +0900
   From: postmaster@copper.point.com
   Message-ID: <19991212190157.01234@copper.point.com>
   To: jean@water.line.com
   Subject: Delivery Notification (DSN)

   MIME-Version: 1.0
   Content-Type: multipart/report; report-type=delivery-status;
       boundary=JUK199912121854870001

   --JUK199912121854870001
   Content-type: text/plain;

   Your message (id MM123456) was successfully delivered to
   ifax@copper.point.com.

   --JUK199912121854870001
   Content-type: message/delivery-status

   Reporting-MTA: dns; copper.point.com
   Original-Envelope-ID: MM123456
   Final-Recipient: rfc822;ifax@copper.point.com
   Action: delivered
   Status: 2.1.5 (Destination address valid)
   Diagnostic-Code: smtp; 250 2.1.5 Recipient <ifax@copper.point.com> ok

   --JUK199912121854870001
   Content-type: message/rfc822

     (headers of returned message go here)
      [[[Replace with actual header data. From D.W.]]]

   --JUK199912121854870001--


















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4.4.2.2 Failure Case Example 1

In this example the receiver determines it is unable to decode the attached TIFF 
file AFTER it has received the SMTP message. The receiver then sends a 'failure' 
DSN.

SMTP Sequence:

  This is the same as the case a). After the sequence, a decode error occurs at
  the receiver, so instead of a 'success' DSN, a 'failure' DSN is sent. 


DSN(to jean@water.line.com):

   Date: Mon, 12 Dec 1999 19:31:20 +0900
   From: postmaster@copper.point.com
   Message-ID: <19991212193120.87652@copper.point.com>
   To: jean@water.line.com
   Subject: Delivery Notification (DSN) - Failure
   MIME-Version: 1.0
   Content-Type: multipart/report; report-type=delivery-status;
       boundary=JUK199912121934240002

   --JUK199912121934240002
   Content-type: text/plain;

   Your message (id MM123456) to ifax@copper.point.com resulted in an error
   in attempt to decode the attached file.

   --JUK199912121934240002
   Content-type: message/delivery-status

   Reporting-MTA: dns; copper.point.com
   Original-Envelope-ID: MM123456
   Final-Recipient: rfc822;ifax@copper.point.com
   Action: Failed
   Status: 5.6.1 (Media not supported)
   Diagnostic-Code: smtp; 554 5.6.1 Decode error

   --JUK199912121934240002
   Content-type: message/rfc822

   (headers of returned message go here)
   [[[Replace with actual header data. From D.W.]]]
    

   --JUK199912121934240002--






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4.4.2.3 Failure Case Example 2

In this example the receiver determines it is unable to decode the attached TIFF 
file BEFORE it accepts the SMTP transmission. [[[It should be noted that the 
results could be the same if instead the receiver could not decode the 'body 
content' of the message. D.W. & V.C.]]]

SMTP sequence:

   S: 220 copper.point.com SMTP service ready
   C: EHLO water.line.com
   S: 250-copper.point.com
   S: 250-DSN
   S: 250 ENHANCEDSTATUSCODES
   C: MAIL FROM:<jean@water.line.com> RET=HDRS ENVID=MM123456
   S: 250 2.1.0 Originator <jean@water.line.com> ok
   C: RCPT TO:<ifax@copper.point.com> NOTIFY=SUCCESS,FAILURE ORCPT=rfc822;
      ifax@copper.point.com 
   S: 250 2.1.5 Recipient <ifax@copper.point.com> ok
   C: DATA
   S: 354 Send message, ending in <CRLF>.<CRLF>
    ...
    ... (the attached file cannot be decoded by receiver)
    ... [[[Replace 'dots' with actual data. From D.W.]]]
    ...
   C: .
   S: 554 5.6.1 Media not supported
   C: QUIT
   S: 221 2.0.0 Goodbye

DSN:

Note: In this case, the previous MTA generates the DSN that is forwarded to 
the original sender. The receiving MTA has not accepted delivery and therefore 
can not generate a DSN.



4.4.3 Extended Mode Receivers that are POP3/IMAP4

NOTE: There are no new definitions here in this document. The definitions
      of disposition-types and disposition-modifiers are defined in
      RFC 2298[9]. This section provides examples on how POP3/IMAP4 devices
      may use the already defined values.









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These examples are provided as illustration only. They should not be interpreted 
as limiting the protocol or the MDN form. If the examples conflict with the 
definitions in the MDN [9] standard, the standard takes precedence and the 
examples in this documents should not be used. 


4.4.3.1 Success Case Example 

If the original sender receives an MDNs which has "displayed", "dispatched" or 
"processed" disposition-type without disposition-modifier, the receiver may have 
possibly received or decoded the attached TIFF-FX file that it sent. It does not 
guarantee that the receiver displays, prints or saves the attached TIFF-FX file 
See Section 4.4.1.1, Discrepancies in MDN Interpretation.

   NOTE: This example does not include the third component of the MDN.

   Date: 14 Dec 1999 17:48:44 +0900
   From: ken_recipient@bronze.dot.com
   Message-ID: <19991214174844.98765@silver.dot.com>
   Subject: Disposition Notification (MDN)
   To: mary@silver.dot.com
   Mime-Version: 1.0
   Content-Type: multipart/report; report-type=disposition-notification;
    boundary="61FD1001_IFAX"

   --61FD1001_IFAX
   Content-Type: text/plain

   This is a Return Receipt for the mail that you sent to
   "ken_recipient@bronze.dot.com". The message and attached files may 
   have been printed, faxed or saved. This is no guarantee that the
   message has been read or understood.

   --61FD1001_IFAX
   Content-Type: message/disposition-notification

   Reporting-UA: ken-ifax.bronze.dot.com; barmail 1999.10
   Original-Recipient: rfc822;ken_recipient@bronze.dot.com
   Final-Recipient: rfc822;ken_recipient@bronze.dot.com
   Original-Message-ID: <19991214174010O.mary@silver.dot.com>
   Disposition: automatic-action/MDN-send-automatically; dispatched

   --61FD1001_IFAX--










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4.4.3.2 Failure Case Example 

If the original sender receives an MDN with an "error" or "warning" 
disposition-modifier, it is possible that the receiver could not receive or 
decode the attached TIFF-FX file. Currently there is no mechanism to associate 
the disposition-type with the handling of the main content body of the message 
or the attached TIFF-FX file.

   Date: 14 Dec 1999 19:48:44 +0900
   From: ken_recipient@bronze.dot.com
   Message-ID: <19991214194844.67325@silver.dot.com>
   Subject: Disposition Notification (MDN)
   To: mary@silver.dot.com
   Mime-Version: 1.0
   Content-Type: multipart/report; report-type=disposition-notification;
    boundary="84FD1011_IFAX"

   --84FD1011_IFAX
   Content-Type: text/plain

   This is a Return Receipt for the mail that you sent to
   "ken_recipient@bronze.dot.com". A decoding error occurred
   in the attached file.

   --84FD1011_IFAX
   Content-Type: message/disposition-notification

   Reporting-UA: ken-ifax.bronze.dot.com; barmail 1999.10
   Original-Recipient: rfc822;ken_recipient@bronze.dot.com
   Final-Recipient: rfc822;ken_recipient@bronze.dot.com
   Original-Message-ID: <199912141823123.mary@silver.dot.com>
   Disposition: automatic-action/MDN-send-automatically; processed/error

   --84FD1011_IFAX
   Content-Type: message/rfc822

   [original message goes here]

   --84FD1011_IFAX--














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4.4.4 Receiving Multiple TIFF-FX Attachments

A received email message could contain multiple TIFF-FX attachments and each 
distinct TIFF-FX file may use different encoding and/or resolution. A received 
email message could include TIFF-FX attachment and non-TIFF-FX attachments.

There is currently no mechanism to identify, in a returned notification, the 
attachments that were successfully decoded from those that could not be decoded.

If the Extended Mode recipient is unable to decode any of the attached files, it 
is recommended that the Extended Mode recipient return a decoding error.


5. Implementation Issues Specific to the File Format

5.1 IFD Placement in TIFF file & Profile S Constraints

Low memory devices, which support resolutions greater than the required Profile-
S may be memory-constrained such that those devices cannot properly handle 
arbitrary placement of TIFF IFDs within a TIFF file.

To interoperate with a receiver that is constrained, it is strongly recommended 
that senders always place the IFD at the beginning of the TIFF-FX file when 
using any of the Profiles defined in RFC 2301.


5.2 Precautions for implementers of RFC 2301 [4]
	
Interoperability testing of the File Format for Internet Fax [4] yielded useful 
information that may help developers avoid the same mistakes.
The following compiled list of TIFF/RFC 2301 [4] errors were encountered during 
interoperability testing and is provided so that implementers can take 
precautionary measures.

5.2.1 TIFF Readers: Be Cautious with Headers

    a) Although Profile S in TIFF-FX requires little-endian, readers 
implementing profiles other than Profile S may be constrained and only read 
little-endian, even when the specifications permit encoding in both little-
endian and big-endian.  Consequently, implementers generating big-endian order 
(bytes 0-1 equal to 4D4Dh) should be aware of potential interoperability 
problems with such constrained receivers.
	 
    b) Do not expect that the byte order (bytes 0-1 of the Image File Header) be 
equal to only "II"(4949h) or "MM"(4D4Dh). They should be able to accept other 
values and exit gracefully.

    c) Do not expect that the "magic number" (bytes 2-3 of the Image File 
Header) be equal to 42 (2Ah) -- other values were found during testing.




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    d) Be careful of the first IFD offset pointing beyond the end of the TIFF-FX 
file.

    e) Be aware that the first IFD offset is not always found on a word 
boundary.


5.2.2 TIFF Writers: Be Cautious in use of IFD

    a) Implementers should be cautious when generating a TIFF profile with a 
second or third IFD û make sure that the offsets for the extra IFDs do not point 
outside the file.

    b) Be careful not to overlap the IFDs with other TIFF profile data such as 
strip image data or header data.

    c) Be aware that some readers have difficulties handling TIFF profiles with 
the following IFD positions: IFD at the end of the profile, IFD intercalated 
with another IFD data like XResolution, DateTime, strip image data, etc.

    d) Be aware that some legacy readers have difficulties handling profiles 
that have child IFDs. There is a high probability that some of these readers 
will have trouble accessing all the child IFDs 

    e) Be aware that some readers do not recognize the GlobalParametersIFD).


5.2.3 IFD Entry Errors

   Implementers should make sure when generating a TIFF profile that:

   a) All entries exist. Missing entries make it impossible to read the image 
data.

   b) Tags will not have two types of data (for example SHORT or LONG).

   c) Tags do not have the wrong type of data (for example RATIONAL instead of 
SRATIONAL). 

   d) The count of type is correct for a specified tag (it is not null and the 
matches the tag ID)

   e) Tags appear in the right order in the IFD.

   f) Tags as PageNumber or ImageLayer have values that match the number of IFDs 
or the image data.

   g) Tags are unique within an IFD.
 



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5.2.4 Strip Errors

    Implementers should make sure when generating a TIFF profile that:

    a) Strip data is not overlapped with another file data

    b) The strip offset does not point outside file

    c) The strip length is not null or the strip offset + strip length
       does not point outside file

    d) There is only one bit order (not more) specified for data storing.

5.2.5 Image Errors

   a) Implementers should be cautious when generating a TIFF profile that the 
type of image tags and the data from the strip data match. (e.g. If in case of a 
B&W image, the PhotometricInterpretation tag value is 0 (bit 0 means white) the 
image will appear inverted).

   b) Implementers should be cautious when generating a TIFF profile that for 
the special color spaces (ITULAB, YCBCR, CMYK) the parameters used for 
transformations are correct and compliant to the specification. 

   c) Implementers should make sure when generating a TIFF profile that the tag 
values for XPosition and YPosition are correct.


5.2.6 Profile Specific Errors
    
   a) Implementers should make sure when generating a TIFF profile that all 
combinations of tag values are correct. Special attention should be given to the 
sets: XResolution, YResolution and ImageWidth and PhotometricInterpretation, 
SamplesPerPixel, and BitsPerSample.

   b) Implementers should make sure when generating a TIFF Profile M that the 
compression used for the layers is correct. Typical errors are for the Mask 
layer not be compressed with a black and white compression and the Background 
and Foreground layer not to be compressed with a color compression.



6. Security considerations

With regards to this document, Sections 5 in RFC 2305 [2] and Section 4 in RFC 
2532 [3] apply.







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7. Acknowledgements

  The authors gratefully acknowledge the following persons who contributed or 
made comments on earlier versions of this memo:
Dan Wing, Ryuji Iwazaki, Graham Klyne, James Rafferty, Kensuke Yamada, and
Richard Coles.



8. References

[1] RFC 2542, "Terminology and Goals for Internet Fax"
    Larry Masinter, Xerox Corporation
    March 1999.

[2] RFC 2305, "A Simple Mode of Facsimile Using Internet Mail"
    Toyoda, K., Ohno, H., Murai, J. and D. Wing
    March 1998.

[3] RFC 2532, "Extended Facsimile Using Internet Mail"
    Larry Masinter, Xerox Corporation
    Dan Wing, Cisco Systems
    March 1999.

[4] RFC 2301 "File Format for Internet Fax", McIntyre, L., Zilles,
    S., Buckley, R., Venable, D., Parsons, G. and J. Rafferty,
    March 1998.

[5] RFC 1891 "SMTP Service Extension for Delivery Status Notification",
    Moore, K., January 1996.

[6] RFC 1893 "Enhanced Mail System Status Codes", Vaudreuil, G.,
    January 1996

[7] RFC 1894 "An Extensible Message Format for Delivery Status Notifications",
    Moore, K., Vaudreuil, G.,
    January 1996

[8] RFC 2034 "SMTP Service Extension for Returning Enhanced Error Codes",
    Freed, N.,
    October 1996

[9] RFC 2298 "An Extensible Message Format for Message Disposition 
    Notifications", Fajman, R.
    March 1998

[10] RFC 822 "Standard for the Format of ARPA Internet Text Messages",
     Crocker. D.,
     August 1982




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9. Authors' addresses

  Vivian Cancio
  Xerox Corporation
  Mailstop PAHV-211
  3400 Hillview Ave.
  Palo Alto, CA 94304 USA
  Telephone: +1-650-813-7591
  Facsimile: +1-650-845-2341
  E-mail: vivian.cancio@pahv.xerox.com

  Mike Moldovan
  G3 Nova Technology, Inc.
  2794 Queens Way
  Thousand Oaks, CA 91362 USA
  Telephone: +1-805-245-4625
  Facsimile: +1-805-245-4214
  E-mail: mmoldovan@g3nova.com

  Hiroshi Tamura
  Ricoh Company, LTD.
  2446 Toda, Atsugi City,
  Kanagawa-Pref., 243-0023 Japan
  Phone: +81-46-228-1743
  Fax:   +81-46-228-7500
  Email: tamura@toda.ricoh.co.jp


Full copyright statement

  Copyright (C) The Internet Society 1999.  All Rights Reserved.

  This document and translations of it may be copied and furnished to
  others, and derivative works that comment on or otherwise explain
  it or assist in its implementation may be prepared, copied,
  published and distributed, in whole or in part, without restriction
  of any kind, provided that the above copyright notice and this
  paragraph are included on all such copies and derivative works.
  However, this document itself may not be modified in any way, such
  as by removing the copyright notice or references to the Internet
  Society or other Internet organizations, except as needed for the
  purpose of developing Internet standards in which case the
  procedures for copyrights defined in the Internet Standards process
  must be followed, or as required to translate it into languages
  other than English.

  The limited permissions granted above are perpetual and will not be
  revoked by the Internet Society or its successors or assigns.




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  This document and the information contained herein is provided on
  an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET
  ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF
  THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
  WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.




Revision history

  [[[RFC editor: Please remove this section on publication]]]
Version 2
 1) Changed first sentence of 4.4.1.1 
 2) Added Sections: 4.4.1.2, 4.4.1.3, 4.4.1.4, 4.4.2.1, 4.4.2.2, 4.4.2.3,
    4.4.3.1, 4.4.3.2 and 4.4.4
 3) Deleted Sections: 6 and 7
 4) Changed heading of Section 4.4.1 
 5) In examples: replaced ifax@water.line.com
    with ifax@copper.point.com as well as other editorial changes
    in the examples through the document.
 6) In examples: changed text in subject field of DSN
 7) In examples: changed text in subject field of MDN
 8) In examples: changed text in text field of MDN
 9) Reworded text through out the document
10) Replaced heading in 5.2.1 [to "TIFF Readers: Be Cautious with Headers"]
11)     "      "        5.2.2 [to "TIFF Writers: Be Cautious in use of IFD"]

 























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