MIME Types for Use with the ISO ILL Protocol
A standard way to send library loan request forms by email
Moulton, R. and M. Needleman, "MIME Types for Use with the ISO ILL Protocol", RFC 2503, DOI 10.17487/RFC2503, February 1999, <https://www.rfc-editor.org/info/rfc2503>.
@misc{rfc2503,
series = {Request for Comments},
number = 2503,
howpublished = {RFC 2503},
publisher = {RFC Editor},
doi = {10.17487/RFC2503},
url = {https://www.rfc-editor.org/info/rfc2503},
author = {R. Moulton and M. Needleman},
title = {{MIME Types for Use with the ISO ILL Protocol}},
pagetotal = 6,
year = 1999,
month = feb,
} RFC text
Contents
Network Working Group R. Moulton
Request for Comments: 2503 United Kingdom
Category: Informational M. Needleman
Data Research Associates, Inc
February 1999
MIME Types for Use with the ISO ILL Protocol
Status of this Memo
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 memorandum describes a set of MIME types for use with the ISO
Interlibrary Loan Protocol (ISO 10160/10161). Two MIME types are
specified below.
The first is a media type to carry objects which are BER [BER]
encoded ISO ILL Protocol Data Units (PDU's). BER are the basic
Encoding Rules used to encode PDU's which have been described using
ASN.1 (Abstract Syntax Notation 1) [ASN.1] .
The second is for use with the associated document delivery
instructions. Document Delivery Instructions (DDI) is an emerging
protocol which enables automatic electronic delivery of items. It
allows a request management system (which might have received a
request for an item via the ISO Interlibrary Loan Protocol (ISO
10160/10161)) to pass details of the request, item, and delivery, to
a delivery module, and to receive back reports on the delivery
process or arrival of an item. It is currently being submitted to the
ISO TC46/SC4/WG4 committee for approval as an ISO standard.
Registration Information
Media type name: application
Media subtype name: iso-10161-ill-1 - for BER encoded ISO ILL APDU's
Media type name: application
Media subtype name: ill-ddi - For associated Document Delivery
Instructions
Required Parameter: transfer-encoding
For BER-encoded PDU's or DDI's, the only current legal value of this
parameter is:
iso-8825-ber
The transfer-encoding parameter describes the way the PDU has been
encoded before being submitted to the transport service (in this case
MIME/RFC822). The two protocols described in this RFC specify their
APDU's using ASN.1 (ISO 8824:1990) and the most common way of
encoding ASN.1 packets is to use the Basic Encoding Rules (BER ISO
8825)
The parameter is included to allow future use of these MIME types
with other encoding schemes. As an example, the ISO 10161 standard
also describes an encoding method using EDIFACT. In the future, other
schemes might also be employed. (Since the EDIFACT encoding is not
currently in use amongst the ISO 10161 and DDI communities, a value
for the transfer-encoding parameter to describe it is not being
registered in this RFC.)
Optional parameter: iso-10161-apdu-type
Valid values are:
ILL-Request
Forward-Notification
Shipped
ILL-Answer
Conditional-Reply
Cancel
Cancel-Reply
Received
Recall
Returned
Checked-In
Overdue
Renew
Renew-Answer
Lost
Damaged
Message
Status-Query
Status-Or-Error-Report
Expired
This parameter is optional and can be provided for informational or
diagnostic purposes. The value of the PDU or DDI type can be
determined from the actual data sent. The use and format of the PDU's
and DDI's is defined in the relevant protocol documents which
describe them.
Examples
Content-Type: application/iso-10161-ill-1; transfer-encoding=iso-
8825-ber; iso-10161-apdu-type=Recall;
Content-Type: application/ill-ddi; transfer-encoding=iso-8825-ber;
Encoding
Since BER encoded material is binary in nature, some form of encoding
is needed when 7bit or 8bit transport mechanisms are employed.
The recommended encoding for BER encoded PDU's is Base64
PDU's per Message
When used to send BER encoded PDU's or DDI's. Each MIME body part
will carry at most one BER encoded PDU or DDI. However, a single MIME
message containing multiple body parts can be used to transport more
than one BER PDU and or DDI.
Security Considerations
There are no known security risks associated with transmitting BER
encoded PDU's in general. However, a particular BER encoded PDU or
DDI may have security considerations that make it inappropriate for
transmittal through public data networks unless appropriate
protection mechanisms, like encryption, are used. Such a situation
might occur, for example, when organizations are exchanging documents
that contain secure or classified information and it is necessary to
keep information about both the material being exchanged and the
exchanging partners confidential.
Interoperability Considerations
BER is an international standard for encoding data meant to be
transferred between two systems that may store data in different
local formats internally [BER].
References
[BER] ISO/IEC 8825:1990 Information Technology - Open Systems
Interconnection - Specification of Basic Encoding Rules for
Abstract Syntax Notation One (ASN.1)
[ASN.1] ISO/IEC 8824:1990 Information Technology - Open Systems
Interconnection - Specification of Abstract Syntax Notation
One (ASN.1)
ISO 10160:1997 Information and Documentation - Open Systems
Interconnection - Interlibrary Loan Application Service
Definition
ISO 10161-1:1997 Information and Documentation - Open Systems
Interconnection - Interlibrary Loan Application Protocol
Specification - Part 1: Protocol Specification
Additional Information:
The National Library of Canada has been designated the maintenance
agency for the ISO ILL protocol. For more information on this MIME
type contact:
Barbara Shuh
Library Network Specialist
Information Analysis and Standards
Information and Technology Services
National Library of Canada
395 Wellington Street
Ottawa, Ontario CANADA
K1A 0N4
Phone: (819) 994-6969
Fax: (819) 994-6835
EMail: barbara.shuh@nlc-bnc.ca
Authors' Addresses
Ruth Moulton
Consultant
65 Tetherdown
London N10 1NH
United Kingdom
Phone: +44 (181) 883 5823
EMail: ruth@muswell.demon.co.uk
Mark H Needleman
Data Research Associates, Inc.
1276 North Warson Road
P.O. Box 8495
St Louis, MO 63132-1806
USA
Phone: (80)0 325-0888 (US/Canada)
(314) 432-1100 x318
Fax: (314) 993-8927
Email: mneedleman@dra.com
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.
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.
AI ELI5
On this page
§1Introduction and Background
The ISO Interlibrary Loan (ILL) protocol is a standard way for libraries to request materials from each other. Libraries use it to ask partners to find and send books or documents.
The ISO ILL protocol messages are encoded using Abstract Syntax Notation One (ASN.1), with the Basic Encoding Rules (BER) as the encoding method. These are international standards for describing and encoding structured data in a language-neutral way. However, when these encoded messages travel through email systems, those systems need to know what kind of content is arriving. This is what MIME (Multipurpose Internet Mail Extensions) types do: they label the content so email programs understand how to handle it.
This RFC registers two MIME types to let email systems properly carry ILL protocol messages and the associated document delivery instructions.
Libraries send special request forms to each other through email. The email needs to know what kind of message is inside, so we give it a label that says 'this is a library loan request'.
§2The Two MIME Types
The RFC defines two MIME types. The first is application/iso-10161-ill-1, which carries BER-encoded ISO ILL Protocol Data Units (PDUs). These are the actual interlibrary loan requests, answers, recalls and other transaction messages that libraries exchange.
The second is application/ill-ddi, which carries Document Delivery Instructions (DDI). DDI is an emerging protocol that allows a request management system to send delivery details to a delivery module and receive status reports back. It works together with the ILL protocol to automate the entire request and delivery process.
The first label is for the actual request message. The second label is for the delivery instructions that say when and how to send the book.
§3Parameters and Encoding
Both MIME types include a required parameter called transfer-encoding. This parameter describes how the data has been prepared for email transport. The currently registered value is iso-8825-ber, which indicates the content is BER-encoded according to ISO standard 8825.
Since BER-encoded data is binary, it cannot be sent directly through 7-bit or 8-bit email systems without additional encoding. The RFC recommends using Base64 encoding to wrap the BER data into text that email systems can safely carry. Base64 converts binary data into a safe ASCII representation.
An optional parameter, iso-10161-apdu-type, can specify the type of the message (such as ILL-Request, ILL-Answer, Recall, or Shipped). While the actual type is always encoded in the data itself, this parameter helps for informational and diagnostic purposes.
The MIME type includes a note saying 'this is BER-encoded binary data'. The actual data is wrapped in Base64 so email can carry it. An optional note can say what kind of message it is.
§4Message Types and Usage
The ILL protocol defines many message types to handle different aspects of the loan process. These include ILL-Request (asking to borrow an item), Forward-Notification (passing a request onward), Shipped (the item is on the way), ILL-Answer (answering a request), Conditional-Reply (cannot fulfill without changes), Cancel (ending a request), Received (item arrived at requestor), Recalled (item must be returned), and several status and notification messages.
In a single MIME message, each body part carries at most one BER-encoded PDU or DDI. However, a message containing multiple MIME body parts can transport multiple requests or responses in one email transmission, making it efficient for bulk transfers.
There are different types of messages for different stages: 'I want to borrow a book', 'I found one', 'I sent it', 'I got it', and so on. Each email can carry one or more messages.
§5Interoperability and Standards
BER is an international standard for encoding structured data designed for systems that may store data differently internally. Using a standard encoding like BER makes it possible for library systems from different vendors and countries to exchange loan requests reliably.
The RFC anticipates that other encoding schemes might be used in the future, such as EDIFACT (which ISO 10161 also describes). By making the transfer-encoding parameter explicit, the MIME types are extensible: new encoding methods can be added without breaking existing deployments.
The National Library of Canada has been designated as the maintenance agency for the ISO ILL protocol. This official stewardship ensures the protocol continues to evolve in coordination with the ISO standardization process.
Using standard ways to code the messages lets computers from different countries talk to each other. The system is designed so new coding methods can be added later if needed.