|GATE - 4/96 - Information - the Key to Sustainable Development (GTZ GATE, 1996, 60 p.)|
CD-ROM and documentation needs of NGOs
by Ferdinand Soethe
In many parts of the world "CD" has become a synonym for easy-to-use tiny, silver disks that store hours of music. The qualities of these disks have found another use after they were discovered as a cheap and reliable medium for mass storage of all kinds of computer data. CD -ROM - " Compact disk as read only memory" - has become a standard feature of most new computers. Time to see how useful this technology can be for NGOs' information publishing needs.
In contrast to the old fashioned LP records, the CD is a digital medium. Anything that you want to store on a CD needs to be converted into the binary language of 1s and 0s. When storing computer data this is very convenient, since the computer handles data in a very similar way. The information you put on a CD is physically stored as a long line of indentations and exaltations (called "pits" and "lands") in a reflective layer just below the clear coated surface of the disk. To restore that information later on, aweak laser beam is run along this spiral of pits and lands, and the reflected light is measured by a light sensing device whose output will then be converted to digital information.
Hardier than floppies
Because information is virtually engraved on the CD and read by a purely optical process, playing back a CD will not deteriorate the medium at all. As long as they are handled carefully, CDs have an almost unlimited lifetime. Since magnetism is not involved it is also safe to store and use CDs close to strong magnetic fields. And while floppy disks suffer badly from spilled liquids or dust, a CD-ROM can easily be wiped off or rinsed with clean water.
CD in real world computing
Like most new technologies, the use of CD-ROMs started out as a creative chaos of competing technologies. While the physical structure of the disks is practically identical and can be read by every CD-ROM drive in any kind of computer, different manufacturers tried to establish their concepts of storing data within the available space. As a result, for a long time, there was no guarantee that any given computer and operating system would be able to read the data that you had recorded on a CD-ROM.
Meanwhile, thanks to a number of well established standards and quasi-standards, CD-ROMs have become one of the most easily exchangable media for computer data. As a matter of fact, the same data on a CD, when properly prepared, can be used by most known computers and operating systems. But keep in mind that information on a CD-ROM can be recorded in a number of different ways depending on your goals and preferences, the type of information you want to store, and how it will be retrieved. The following list mentions just a few of these to give you an idea:
- CD-DA: The recording format of the digital audio disk. - ISO 9660: A general purpose format for storing all kinds of computer data.
- Photo CD: Developed by Kodak and Philips to store digital images in number of different resolutions.
ISO 9660 the "Workhorse Format"
Today, the most important of these standards is ISO 9660. Created with the backing of major players in the computer industry and later established as an international norm, ISO 9660 describes a technical format that allows you to store up to 650 Megabytes (MB) of computer files on a single CD-ROM.
Like the file systems of all major operating systems, this space can be subdivided into up to eight levels of directories and subdirectories which contain the individual files. Note that there are restrictions on the character set and the maximum length of file and directory names to ensure that the files can be read and used in all environments.
The practical uses of CD-ROMs are numerous, reaching from publishing information through backing up data to exchanging complete preconfigured software setups between the different offices of an organisation.
The most important use for NGOs today, however, is probably information publishing. So let's focus on this and narrow it down even further to the key aspects of publishing text and image information. In doing so I deliberately exclude the high end multimedia publishing of video and audio information. For one thing because software and hardware as well as the knowhow required is beyond most NGOs today. And secondly because there is a new and better solution for these applications (the Digital Video Disk) that is just about to become a new standard.
Publishing text and images on CD-ROM
There are three major techniques to publish information on a CD-ROM.
- In the file-based approach you create a logical strucure of directories and subdirectories and store the information as files in the different directories. By placing an additional table of content-files in each directory, the user of CD-ROMs can find the required information.
- In a second approach, all information is placed in some form of database, which allows quick and easy access to the information and helps the user to access the information in different ways.
- Using Word Wide Web technologies as a third way you can combine the simplicity of the first with much of the powers of the second approach. The strength of the file-based approach is its simplicity and the fact that very little software is required. If all you have is text, it might be sufficient to export it as simple ASCII-text files from your word processor, create the table of content files and you are done. The user of the CD could then use any kind of text-viewer or word processor to access the information.
But there are clear limits to this approach. Searchability of the information is one of the problems that you will encounter along the way. While you can easily write and include software on the CD that will do full text file searches of the content, keep in mind that you might be searching some 650 MB of information. So unless you are dealing with extremely patient users, a simple search programme just won't be good enough.
The database-oriented approach can solve this problem. Unfortunately most cheap and easy-to-use database programmes are only available for one operating system. And while ISO 9660 allows access to the files on a CD-ROM from different operating systems, it does not make software programmes run in different environments. A standard solution to this problem is to include different versions of the software for each operating system. But be aware that you might have to pay a lot more to find a solution that is easy to use, performs well and provides viewer-software for most major operating systems. And please note that a standard user licence for most database packages will not grant you the right to hand out the software to all your CD clients.
Using technologies of the Word Wide Web on a local CD-ROM can be an elegant and free solution to this problem. Presenting your information in HTML, the document format of the World Wide Web, not only can you enhance your text with most features of a modern word processor (fontstyles, headlines, tables etc) but you can also integrate images and even interactive components. And because HTML was conceived in the heterogeneous environment of the Internet, there is free viewer-software (called a "browser") to view, use and print the content for most operating systems and hardware platforms.
In addition to these tempting options, HTML allows you to interconnect your documents with clickable links (pieces of text or images that when clicked will take you to another document). This is a very easy way to establish crossreferences, active tables of content and even clickable keyword indexes. With some more effort you can even use free full text indexing technology (i.e. WAIS) to provide full text retrieval of the documents on your CD-ROM.
Because the World Wide Web and HTML have become so popular, HTML is also understood by most modern word processors, so that carefully prepared documents on your CD can be easily re-used without losing the layout.
Think about copy protection
When chosing your publication method, consider that data on a CD-ROM is just as easily copied as a file on a hard disk. If you need to keep people from "reusing" your data in a number of inventive ways, you'll have to figure out some copy protection scheme.
With file-based systems, copy protection is quite difficult, and although you can use encryption schemes, that often takes away the simplicity of this approach. An easier way to achieve reliable protection is to use a customised database software and disable the mechanisms to extract information (Save to file, copy to clipboard etc.). Consider that it is often sufficient to prevent users from extracting all the information while still allowing excerpts.
Manufacturing a CD-ROM
The preparation of content always takes place on conventional media such as hard disks. Consider that you'll need at least as much free space on your hard disk as you want to store on your CD-ROM.
Once the information is on your computer, production of the actual CD can happen in two different ways: You can burn your own or have a CD factory do it for you.
Since CD-ROM and Audio CDs have the same physical format, you can take advantage of the facilities of the music industry and have your CDs produced alongside Beethoven and Madonna. As you can see in the flowchart, all you really have to do is deliver the data to the company and check the intermediate and final versions.
In terms of price and production time this is an interesting option as soon as you need more than 40 copies of your CD. Since the process is optimised for mass production, cost will drop significantly with higher volumes (500 or more) and often get close to the cost of replicating a floppy disk (while providing 500 times more space).
As an additional benefit, most production facilities will also take care of printing a label on your CD and package the disk in the square jewel boxes that you know from audio CDs. If your intended audience is spread all over the globe, enquire about alternative packaging that is lighter and can be shipped more cheaply.
"Burn your own"
"Burning" or "mastering" your own CD's is a technology that has just now become affordable as the prices for the recording "CD-R"drives and premastering software have dropped well below US$ 1,000. Note that you always need premastering software because you can't just copy files to the disk with your operating systems.
After the data has been prepared for writing with the premastering software, pretty well all you have to do is insert a blank disk (about US$7) in the CD-R drive, start the recording process and wait about 30 minutes for it to finish. Of course you'll still need to label the disk, but otherwise this process will turn out a perfectly normal CD that can be read in any CD-ROM drive. To find out more details about burning your own CD, the drives and the software, take a look at PC Magazine Vol 15 No 7 (April 1996).
Get one anyway
Apart from the above mentioned uses, a CD-R can be useful in a number of other ways:
- Used as a backup medium, it is a very reliable medium with an extremely long life time.
- Doing your own premastering, you can save time and money in mass-production by delivering a finished and tested master CD to the factory.
- If you need to ship larger amounts of data, you can create a single CD and avoid all the problems of incompatible tape streamers or backupsoftware.
Consider the Multisession CD
If you decide to purchase a CD-R drive, try getting a drive and software that can handle multiple sessions. In practical terms this means that you can store some files on the CD, use it for a while and add more data in further "sessions" later on. You might even allow others to add a session with their own CD-R drive and return the CD to you before you add the final session that locks and write protects the CD for good.
Co-produce and save
Note however that some older CD drives might not be able to read anything but the first of these sessions. So if you are aiming at a wider audience, you'd probably want to create a single session CD for the final distribution.
Co-producing a CD can be an attractive option. Most NGOs won't need 650 MB of space for their information. So why not get together with other groups and share a disk. The benefits of such a joint venture speak for themselves:
- Because of the higher numbers of CDs you can probably go for factory production and cut your cost per disk.
- If you need database solutions and agree on a software, you will probably get a much better deal.
- Since every NGO reaches a different audience, your information will likely be seen by far more people.
And even if you are planning to sell your information for more than just replication cost, this approach is still viable. Just use a software that allows a user to unlock "your" part of a CD with a password that she needs to purchase from you.
Reading the introduction above will hopefully give you a basic understanding what CD-ROM publishing is about.
However, it does not answer a number of questions you need to ask to determine if this is a useful technology for your organisation. To 11st just a few you need to find out - if you really need to publish large volumes of information that justify the technology If the information can be distributed on a few floppy disks, think twice before using a CD. I was able to publish all important documents from the UN World Conference on Human Rights in Vienna and its preparatory conferences on less than five floppy disks. - if a majority of your audience already has a CD-ROM drive or is planning to get one in the near future. If not, the increased cost of smaller print runs can easily eat up any savings you achieve with your CDs.
And finally, please do consider the impact on resources and the environment. Although a CD can theoretically save some 300,000 pages of printed paper, you often use just a fraction of that space while the high environmental impact of producing media and drives remains the same. Floppy disks can be reused many times and paper can be recycled to paper; an outdated CD may at best become a jewel case, while it normally ends up as long life garbage.
A practical example
Let's say you have worked for an umbrella organisation of 40 human rights groups around the world. For the annual conference you need to prepare a reader with a large number of papers and background information.
Because of the amount of material it seems impractical to send the reader by e-mail, so you decide to create a CD-ROM in order to save on printing and shipping. In an attempt to simplify your work, you appeal to all participants to send their contributions by e-mail or on disk and to use one of a few previously established document formats (i.e. ASCII-Text, Winword 5, HTML). Contributions that arrive in printed form are scanned and converted to text and images.
You are planning to publish the information on CD -ROM and also offer it on the World Wide Web. So you opt for HTML and convert all documents to HTML pages with text and images. As the deadline draws closer, you create a new directory tree on your hard disks and think up a logical directory structure for storing the individual documents.
Next you connect to the internet and download the current version of a free WWW viewer-software (i.e. Mosaic) for every operating system that your readers use. Each package is placed in a seperate subdirectory, and perhaps you'll add some instructions for installing the individual version. Don't forget to add a page that lists all the different versions and tells your reader which one to install on her operating system.
Once all documents are in place you add a number of overview documents (also in HTML) that allow access to the information by mouseclick and offer different access routes (i.e. by organisation, subject, region, etc). Since you have planned well there is time left to add additional cross-references between different documents and further enhance the informational content of the disk.
Now you can create the CDs. Since there are not too many
participants you decide to produce all of them on your CD-R drive and use the
multi session technique to be able to add more later on. You include a note
asking participants to bring the CDs with them to the conference.
Then you place the materials on your World Wide Web Server to reach an even wider audience. Because the documents were prepared using World Wide Web technologies, you can do that with out much extra work. Once the conference has begun, you start gathering the reports of the working groups and store them in your computer for further processing. Your first reader probably didn't take up the whole 650 MB capacity of the CDs. So you can offer to update the original reader disk and add the information from the conference in a second session.
When preparing the new material for the update you have the choice of just adding new documents or replacing some of them with modified versions. That way you can completely integrate the new documents with the previous reader.
When you're done, all you have to do is write the new information as the final session to the CD-ROM to obtain a completely write protected CD and mail it to the participants.
How to handle your CD-Rom
Although CDs are insensitive to many foes of the floppy disk, the tiny silver disks are by no means indestructible, and should be handled with great car. To ensure the uninhibited passing of the laser beam throughout the clear top (or rather bottom) layers of the disk, it is of utmost importance to protect the clear coating layer against scratching and abrasion.
The best way to achieve this is to always store the CDs in a clean box when they are not in use. If you use a small number of CDs frequently, consider getting a drive that uses so-called "caddies". Instead of handling the bare CD - ROM; each CD is permantly stored in a caddy and inserted with it into the drive, thus avoiding wear and scratching.
If your CD gets just a bit dusty or somebody has left fingerprints on the surface, you can usually wipe it with a clean, soft piece of cloth. Just make sure to always wipe the CD in a radial movement from the centre to the rim because if you happen to scratch the surface, the error correction of a CD can deal much better with scratches in this direction.
Creating a CD-ROM