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NLS: That All May Read

Digital Talking Book Distribution Analysis

For: Digital talking book distribution analysis. Task 1 - Distribution system analysis and selection (Final report : September 16, 2005)

Section 1 – Introduction

1.1 Background

The National Library Service for the Blind and Physically Handicapped (NLS) of the Library of Congress (LOC) administers a free library service to approximately 500,000 eligible residents of the US and US citizens living overseas who cannot read, hold or handle print media because of visual and/or physical disabilities.  Under a special exemption of the US copyright laws and with the cooperation of authors and publishers who grant permission to use non-covered copyrighted works in the program, NLS selects and produces annually about 2,000 full-length book titles and 45 magazines in a specialized 4-Track, 15/16 ips recorded cassette (RC) format.  NLS also produces annually about 40,000 specially-designed playback machines which enable readers in the program to play the recorded cassette books and magazines produced in specialized format.

A cooperating nationwide network of 57 regional (RL) and 77 subregional (SRL) libraries currently store approximately 23,000,000 and loan about 20,000,000 RC books per year to readers in the program, while about 3,500,000 copies of cassette magazines are provided annually from manufacturers on a one-way, disposable circulation basis.  Operations in network libraries are supported by a combination of state, local and private funding, while NLS contracts with manufacturers for the provision of direct circulation magazines.  Virtually all circulation of books, and all circulation of magazines, is on a mail-order basis which is performed by the US Postal Service (USPS) and the costs of which are covered under a special Congressional appropriation for the same ("Free Matter for the Blind").

While cassette technology has been the backbone of the program for almost 30 years, it is outdated in several respects and is nearing the end of its useful life. Compared to cassette-based technology, digital audio technology offers significant improvements to readers in the program, network libraries, and NLS. NLS has therefore determined to implement digital audio technology as the framework of the future system. Following extensive research, NLS has established a digital audio book standard (ANSI/NISO Z39.86) and is selecting a digital file compression algorithm to be used to compress the size of files required for audio books yet retain acceptable audio quality.

While NLS anticipates that ultimately most patrons of the program will download digital reading materials from the Internet using a variety of broadband channels, and store and read books and magazines on portable playback machines designed specifically for use with such a delivery system, several major technological and economic impediments related to the provision of broadband Internet access to patrons of the program are expected to continue for some time. Therefore, NLS has decided that reliance upon such a delivery system must be postponed until technological advances make it economically feasible for most patrons in the program.

NLS has performed extensive research and determined that the first digital audio book distribution system will be based upon a high-density, solid-state Flash Memory medium, using a "one-book, one-object" circulation protocol (i.e., as is currently used), with books being delivered to readers and returned from readers via the USPS.   The transition to this system is planned to begin in 2008, and will require approximately five years to complete.

In addition, the entire collection of digital audio books will be available for download by patrons and libraries, probably in 2007, and certainly by the time digital audio book distribution from libraries is begun.  This will allow "early adopter" readers who strongly wish access to a book to obtain it directly from the download site.  Libraries will also be able to download books for which they are not provided copies (e.g., most of the 20,000 retrospective book titles planned to be available by 2008), and make copies if necessary.

1.2 Objectives

The objective of this project is to first model, evaluate and select which of three distribution system options for flash memory-based digital audio books should be implemented, and then to develop the design of the system for the selected option, specifications for that system design, and a transition plan to effect implementation.  The three distribution options to be evaluated are the following:

Option 1: All Mass Duplication of digital talking books (DTBs)
Uses the current distribution model for cassette books, whereby all copies of all titles produced are mass-duplicated at production facilities and shipped to network libraries, where they are stored in collections and circulated to patrons.
Option 2: "Hybrid" System
The most popular titles, constituting a minority of titles but a majority of circulation, would be mass-produced and shipped to network libraries for storage and circulation but the less popular titles, constituting a majority of titles but a minority of circulation, would be produced on demand and circulated from one or possibly several special Duplication-on-Demand (DOD) Centers as instructed by the libraries via telecommunicated orders.  However, all reader contact and communications would be with network libraries, and none with the DOD Centers, although patrons would return books loaned from the DOD Centers to the Centers.  DOD Centers would maintain no DTB collections; DTB cartridges would be erased and reused.  This option represents a deviation from current and long-standing business practices between the NLS and libraries and effectively shifts some distribution costs from libraries to the NLS, but still retains a strong element of current practices (i.e., the storage of some titles and the circulation of most copies from library collections, and all patron contact with libraries).  Other variations on the Hybrid concept, including a "time-based" model whereby most or all mass-duplicated titles "migrate" from libraries to DOD Centers after a specified number of years, implemented independently from or in conjunction with the "title-based" Hybrid, are undergoing further evaluation.
Option 3: All DOD
Copies of all DTB titles would be distributed from DOD Centers.  There would be no mass-duplication of DTB titles, no storage of DTBs in library collections and no DTB distribution from libraries.  This option represents the greatest deviation from current practices and the greatest shift of distribution costs from libraries to the NLS, but retains the element of all patron contact being with network libraries.

This final report for Task 1 of the project describes the modeling of the estimated costs of the aforementioned DTB distribution options, using a spreadsheet-based mathematical model of the future distribution system, and the application of an evaluation matrix towards the evaluation of the distribution options which considers both economic and non-economic factors.  The development of the estimated values for the important factors, or "key variables," which are used in the cost model are described and documented, and the logic of the model is described.  The factors and factor weights used by the evaluation matrix are also described, and a distribution option is recommended for implementation.

1.3       Scope

The scope of the evaluation of the DTB distribution systems options is limited in the following ways:

1.4       Constraints, Caveats, Limitations and Assumptions

The following are the major constraints, caveats, limitations and assumptions which apply to the evaluation of the DTB distribution options performed in Task 1:


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Posted on 2006-11-30