Network Working Group K.Mimura Internet-Draft: draft-ietf-fax-gateway-options-07.txt K.Yokoyama Intended Category: Informational T.Satoh K.Watanabe C.Kanaide TOYO Communication Equipment July 20 2004 Guideline of optional services for Internet FAX Gateway Status Of This Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. 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 obsolete 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. Copyright Notice Copyright (C) The Internet Society (2004). All Rights Reserved. Abstract An Internet FAX Gateway provides functions which translate a facsimile?@between the general switched telephone network (GSTN) and the Internet. This document provides guidelines of optional services and examples of an Internet FAX Gateway, with respect to the onramp gateway and offramp gateway. This document does not intend to specify the actions to which the IFax offramp and onramp gateways (defined in [3]) conform. This document covers drop duplication, automatic re-transmission, error behavior, when sending return notice, and the keep log for an offramp gateway. Also covered are examples of authorization by DTMF (Dual Tone Multi-Frequency) and the keep log for an onramp gateway. Mimura, et. al. Expires January 2005 [Page1] Internet Draft Guideline of optional services July 2004 for Internet FAX Gateway Table Of Contents 1. Introduction 1.1 Intellectual property 2. Optional Services for an Offramp Gateway 2.1 Drop duplications 2.2 Automatic re-transmission in the occurrence of a delivery error 2.3 Error behavior 2.4 When sending return notice 2.5 When a transmitting error occurs in a return notice 2.6 Keep log 3. Optional Services for an Onramp Gateway 3.1 Example of user authorization 3.2 Keep log 4. Security Considerations 5. References 5.1 Informative groups 5.2 Normative groups 6. Full Copyright Statement 7. Contact 1. Introduction An Internet FAX Gateway can be classified as an offramp gateway and onramp gateway. This document provides information on the guidelines of optional services and examples of an Internet FAX Gateway. This document covers drop duplication, automatic re-transmission, error behavior, when sending return notice, and the keep log for an offramp gateway. Also included are examples of authorization by DTMF and the keep log for an onramp gateway. A more detailed definition of onramps and offramps is provided in [1]. Information on recommended behaviors for Internet FAX Gateway functions are defined in [2]. The scope of the Internet FAX Gateway defined in this document is shown below. 1) The format of image data is a data format defined by "simple mode" in [3]. 2) The operational mode is "store and forward," as defined in Section 2.5 of [1]. 1.1 Intellectual property The IETF has been notified of intellectual property rights claimed in regard to some or all of the specification contained in this document. For more information, consult the online list of claimed rights at . Mimura, et. al. Expires January 2005 [Page2] Internet Draft Guideline of optional services July 2004 for Internet FAX Gateway 2. Optional Services for an Offramp Gateway 2.1 Drop duplications Sometimes overlapped mail is received by an offramp gateway. In such cases the offramp gateway is required to drop the overlapped mail. The purpose of this is to prevent the offramp gateway from transmitting the overlapped facsimile data to a facsimile device over the GSTN. For example, an MTA (Mail Transfer Agent) is set so that it puts mail with a different destination address in one mailbox. When the MTA receives broadcast mail (mail of more than one destination address), some kinds of MTAs copy the mail in one mailbox. Then, the offramp gateway uses POP to receive the mail from the MTA. As a result, the offramp gateway receives duplicate mail from the MTA. Discussion of the duplicate message detection mechanism is entrusted to other documents. 2.2 Automatic re-transmission in the occurrence of a delivery error An offramp gateway MAY add a function that automatically tries to send facsimile data again if delivery failure occurs. If this function is added, the retry times and retry interval MAY be specified as options by the administrator of the offramp gateway. If this function is set, a return notice SHOULD be sent only when the specified number of retries has been completed and the last facsimile transmission is an error. When transmission is suspended by the error, transmission is again started to send an error page on the next transmission. For example, assume that an offramp gateway is sending a total of Five pages of facsimile data. But, an error occurs after two pages of normal transmission and the transmission is stopped. The offramp gateway should re-transmit the facsimile data, beginning with page 3. 2.3 Error behavior Retransmission behavior depends on the kinds of errors. In Calling Errors, such as a busy signal, line errors, and so on, the offramp gateway can perform retransmission. In Connecting Errors, such as a paper error, stop event error - but not a FAX error (voice response) - the offramp gateway sends a return notice to the sender without any retransmission. Thus, Calling Errors can probably be recovered, but Connecting errors can rarely be recovered. Mimura, et. al. Expires January 2005 [Page3] Internet Draft Guideline of optional services July 2004 for Internet FAX Gateway 2.4 When sending return notice When an offramp gateway receives broadcast mail, there are two ways to send a return notice. 1) An offramp gateway sends a return notice as soon as an error occurs. 2) An offramp gateway sends a return notice after every completion of the specified number of transmissions. These features should be options selected by the user. Example The source user is requested to send one facsimile data to 20,000 addresses, but encounters many errors for more than 1000 addresses. If an offramp gateway sends a return notice as soon as an error occurs, the source user would receive more than 1000 return notices from the offramp gateway. But, the source user can receive a return notice as soon as one error occurs. If the offramp gateway sends one return notice for every ten transmissions, the source user would receive only one-tenth of the return notices. 2.5 When a transmitting error occurs in a return notice When an offramp gateway fails in the transmission of a return notice, the Internet FAX Gateway SHOULD process the notice in either of the following ways. 1) When the gateway has a log information preservation function, the error information SHOULD be recorded to a log, and processing SHOULD end. At this time, the administrator of the gateway system SHOULD be notified of these errors using a specific process (for example, SMTP). 2) If the gateway does not have a log information preservation function, the administrator SHOULD be told about the failure, and processing SHOULD end. 3) If the gateway has a high hardware capability and sufficient time margin, it is a beneficial service to perform the following processing. When notice of a result fails in transmission, the fixed time interval is vacated, and the output of the notice is repeated for a specified number of times. Even if the specified number of times continues to fail, the error information is recorded to a log, and processing is finished. Also, at this time, the administrator of the gateway system SHOULD be notified of these errors by a specific process (for example, SMTP). Mimura, et. al. Expires January 2005 [Page4] Internet Draft Guideline of optional services July 2004 for Internet FAX Gateway 2.6 Keep log An offramp gateway MAY have a function which keeps the information listed below as a log. For security and message traces, the Internet FAX Gateway MAY use the following format for a system log or event log of the Operation System. - Date and time when transmit request is received - Source address - Destination address - Date and time when transmitted over the GSTN - Date and time when transmission over the GSTN was finished - Number of real transmitted pages - Byte count of transmitted data - Type of data (resolution) - Occurrence of errors - Number of retries automatically sent - Date and time of transmission of delivery notice The goal of the log information preservation function is mainly to improve security or charge calculation processing. When the hardware system is equipped with recording media (HDD, FDD, etc.), the log information SHOULD be saved as a log file. The following are three opportunities to save log information. 1) When an offramp gateway receives a distribution demand. 2) When an offramp gateway starts distribution. 3) When an offramp gateway ends distribution. When the hardware system does not use a recording medium, log information cannot be saved locally. In this case, it is desirable to use the save function at other PCs using existing network communication means, such as a function to save log information as a file using Network File System, SMTP, SNMP, or the function to periodically print log information. To strengthen security, it is desirable to save log information in the Internet FAX Gateway using a database system. 3. Optional Services for an Onramp Gateway 3.1 Example of user authorization An onramp gateway MAY have a user authorization function to confirm that the user is authorized to transmit data. In the case of onramp action, there are many methods to send authentication information. The method chosen depends on the provider's services. Consequently, an example is not described. Mimura, et. al. Expires January 2005 [Page5] Internet Draft Guideline of optional services July 2004 for Internet FAX Gateway 3.2 Keep log An onramp gateway MAY have a function that keeps information as a log. For security and message traces, the Internet FAX gateway MAY use the following format of a system log or event log of the Operation System. - Date and time when transmission request was received - Source address - Destination address - Date and time of transmission over the GSTN - Date and time when transmission over the GSTN was finished - Date and time of transmission over the Internet - Number of real transmitted pages - Byte count of transmitted data - Type of data (resolution) - Occurrence of errors - Number of retries sent automatically - Date and time of transmission of delivery notice The purpose of the log information preservation function is mainly to improve security or charge calculation processing. When the hardware system is equipped with recording media (HDD, FDD, etc.), the log information SHOULD be saved as a log file. The following are three possible opportunities to save log information. 1) When an onramp gateway receives a distribution demand. 2) When an onramp gateway starts distribution. 3) When an onramp gateway ends distribution. When a hardware system without a recording medium is used, log information cannot be saved locally. In this case, it is desirable to use a function that saves at other PCs using existing network communication means, such as a function to save log information as a file using Network File System, SMTP, SNMP, or a function that periodically prints log information. In order to strengthen security, it is desirable to save log information in the Internet FAX Gateway using a database system. 4. Security Considerations An offramp and onramp gateway MAY have a user authorization function to confirm that they are authorized to transmit facsimile data. Encryption of facsimile data could be performed by the existing SMTP, using an available security technique. The security consideration sections of [3] apply to this document. Mimura, et. al. Expires January 2005 [Page6] Internet Draft Guideline of optional services July 2004 for Internet FAX Gateway 5. References 5.1 Informative groups [1] L. Masinter, "Terminology and Goals for Internet Fax", RFC 2542, March 1999. 5.2 Normative groups [2] K. Mimura, K. Yokoyama, T. Satoh, C. Kanaide, "Internet FAX Gateway Functions", draft-ietf-fax-gateway-protocol-11.txt, July 2004. [3] K. Toyoda, H. Ohno, J. Murai, and D. Wing, "A Simple Mode of Facsimile Using Internet Mail", RFC 2305, March 1998. 6. Full Copyright Statement Copyright (C) The Internet Society (2004). 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. 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. Mimura, et. al. Expires January 2005 [Page7] Internet Draft Guideline of optional services July 2004 for Internet FAX Gateway 7. Contact Katsuhiko Mimura TOYO Communication Equipment CO., LTD. 2-1-1 Koyato, Samukawa-machi, Koza-gun Kanagawa-pref., Japan Fax: +81 467 74 5743 Email: mimu@macroware.co.jp Keiichi Yokoyama TOYO Communication Equipment CO., LTD. 2-1-1 Koyato, Samukawa-machi, Koza-gun Kanagawa-pref., Japan Fax: +81 467 74 5743 Email:keiyoko@msn.com Takahisa Satoh TOYO Communication Equipment CO., LTD. 2-1-1 Koyato, Samukawa-machi, Koza-gun Kanagawa-pref., Japan Fax: +81 467 74 5743 Email: zsatou@toyocom.co.jp Ken Watanabe TOYO Communication Equipment CO., LTD. 2-1-1 Koyato, Samukawa-machi, Koza-gun Kanagawa-pref., Japan Fax: +81 467 74 5743 Email: knabe@toyocom.co.jp Chie Kanaide TOYO Communication Equipment CO., LTD. 2-1-1 Koyato, Samukawa-machi, Koza-gun Kanagawa-pref., Japan Fax: +81 467 74 5743 Email: kanaide@toyocom.co.jp Mimura, et. al. Expires January 2005 [Page8] Internet Draft Guideline of optional services July 2004 for Internet FAX Gateway Revision history 00a 31-Oct-2000 Initial draft. 01a 21-Feb-2001 Rebuild next definition 2.6 keep log 3.2 keep log Added next definition 2.5 When a transmitting error occurred in return notice 02a 22-May-2001 Rebuild next definition 2.6 keep log 3.2 keep log 4. Security Considerations 03a 28-June-2001 Rebuild next definition 3.1 Example of User authorization 04a 19-September-2001 Rebuild next definition 4. Security Considerations 4a 20-March-2002 Corrections and clarifications. Dropped reference to RFC2119. Moved Intellectual Property after section 1. Fixed Security considerations. 4b 25-March-2002 Reword first paragraph of section 2.1 Arrange 5. References again. 06 25-July 2004 Corrections and clarifications. 07 20-July-2004 5. References split to Informative and Normative Mimura, et. al. Expires January 2005 [Page9]