This is part three of a continuing series on the application of the Service Oriented Architecture (SOA) design pattern to library systems. In the first part, the SOA concept was compared to a transportation network and the basic foundation for defining SOA was set down. The second part described what a "service" in SOA could be and proposed an example using OCLC's WorldCat interface with item status information being pulled from a library catalog system. That part also left off with a teaser about the juxtaposition of "inventory control system" with "local catalog system" — a foreshadowing of the topic of this post: what to do about the Monolithic (er... "Integrated") Library System.
How did we get where we are today?
Wikipedia has the most concise description of the state of library automation today:
Before the advent of computers, libraries frequently used a card catalog to index its holdings. Computers were used to automate the card catalog, thus the term automation system. Since the late 1980s, multi-tasking modules allowed business functions to be integrated. Instead of having to open up separate applications, library staff could now use a single application with multiple functional modules.
Adapted from "Integrated library system." Wikipedia, The Free Encyclopedia. 20 Sep 2006, 19:29 UTC. Wikimedia Foundation, Inc. 20 Sep 2006 http://en.wikipedia.org/wiki/Integrated_library_system&oldid=76840266#History.
As this article points out, libraries have a grand tradition of applying technology to its business problems. These "integrated library systems" (ILS) — so named for their unified functions of public search, circulation (check-in/check-out), acquisitions, and cataloging (description) — propelled library staff productivity to magnitudes not seen before. "Those systems," notes Marshall Breeding, "came quite close to delivering comprehensive automation for libraries."
So why change? Marshall goes on to say, "the ILS remains shackled to the antiquated print-based paradigm for library automation." Today's integrated library system is ill-equipped to handle the desired integration of formats (audio, video, journal article) and delivery mechanisms (online versus on-site) of our users. It is also not a nimble platform; as a single, all-encompassing application, bug fixes and new functionality across the entire must be wrapped in a software distribution to be released to users.
This post is not intended to be an exhaustive examination of the problems with the software design model of current ILS applications; there is a growing body of analysis and commentary on that point. Rather, the rest of this post seeks to point a way forward — a path that involves the dis-integration ("un-integration"? or, as Marshall put it, "re-integration"?) of the integrated library system.
What is the Integrated library System?
What I propose is that we think back to a time before we had the luxury of an integrated library system, and remember the pieces that over the past few decades we have worked so hard to bring together.
Discovery Tool / Indexing Tool
Sometimes called a "search engine", the term "Discovery" more accurately describes the activity of our users. There is more here, though, then just splitting off the public interface of the existing ILS. A true SOA Discovery Tool is more akin to Roy Tennant's "Only Librarians Like to Search, Everyone Else Likes to Find" mantra — there should be one Discovery Tool for the user that, a la Google or Amazon, searches across the entire content space to bring the best information results back to the user. Maybe it helps to think of the Discovery Tool as a portal through which the user finds any nugget of information available in the library's sphere of content; that nugget may be a book, a journal article, a web page, a video, a dissertation, or any other piece of content.
Speaking of Roy's mantra, I may be showing a bit of a bias here towards one particular solution by pairing the Discovery Tool with an Indexing Tool. The underlying presumption here is that there will be One Common Index for all library content. Given the issues surrounding metasearch (particularly the speed at which a metasearch query can be executed), getting a zippy response for a SOA interaction really requires that an index already exist that is used to answer the query. This bias is fueled, admittedly, by OhioLINK's fortunate position of storing and serving much of the content under license from publishers/producers from our own servers. When you actually have access to the content and underlying metadata, you can think about creating One Common Index for all of that content. So use of the Discovery Tool is inexorably linked to the Indexing Tool.
Inventory Control Tool
Based on the previous posting, you could probably guess that this tool was coming. What else would you call an activity that keeps track of what items are located where in, if you'll pardon the analogy, a warehouse full of books? Inventory Control is a problem that has been solved time and time again with greater and greater efficiency by industries other than libraries, and I think it is about time that we start to be able to take advantage of some of those efficiencies. (Interestingly enough, I've noticed an increase of "global logistics" companies on the ALA exhibitor floor. I stopped and talked with one of them, and he mentioned some of the work that his company was doing — fascinating stuff for perhaps another blog post someday.)
A library's inventory control challenge is modestly similar to that of a video rental store: we need to track what is within our confines and what has been "rented." That leads us right into the next tool.
Point-of-Sale (a la video rental) Tool / User Directory Tool
If our inventory control is similar to that of a video rental store, our "check out" is their "rental" and our "check in" is their "return." If we can make that analogy, our circulation system is a kind of Point-of-Sale system.
If that analogy holds, then their customer database is like out patron database. In any case, we will need a User Directory Tool where demographic information is kept as well as information about users' "rentals." The User Directory Tool can also be a source of authentication and authorization as well as other functions such as storing recommendations and annotations. (More on this topic to come at a later time.)
Ordering and Receiving Tool
This, quite frankly, has to be the least "library" of all of the components that make up an ILS. After all, doesn't just about every business have some sort of acquisitions, receiving, and accounts payable workflow? Is there anything about an Ordering and Receiving Tool that is unique to the libraries? From a broad perspective, what is being "bought" is a description of an item — a record number, if you will, coming out of the Description Tool (see below).
If ordering and receiving is the least "library-like" aspect of the ILS, item description has to be the most uniquely library activity. Who else gets as passionate about how items are described? Large parts of our professional training are devoted to the creation and use of descriptive metadata. (For the outsiders peeking into the library profession through these postings: yes, it's true...this is what most librarians, at some level, get really excited about.)
Unlike the integrated library systems in use today, however, our next generation Description Tool must be multi-lingual: MARC
There is more to come in our exploration of general Tools and specific Services that we might find in a Library Service Oriented Architecture environment. The next posting in this series, however, will explore the important distinction between SOA and another buzz-phrase making the rounds: "Web Services".
Thanks go out to Richard Wallis at Talis and Lorcan Dempsey at OCLC for their comments so far. I'm on the home stretch towards a plateau in this series and which point I'll take a step back, absorb your observations, and reflect them back out in subsequent postings. Everyone else, please feel free to join in on the conversation as well, whether it be through comments here or commentary elsewhere.
[20060921T0820 Missed the "p" in Lorcan's last name -- my humble apologies, Lorcan.]
The text was modified to update a link from http://en.wikipedia.org/wiki/Integrated_library_system&oldid=76840266#History to http://en.wikipedia.org/wiki/Integrated_library_system?oldid=76840266#History on January 13th, 2011.
The text was modified to update a link from http://blogs.talis.com/panlibus/archives/2006/09/a_library_soa_e.php to http://blogs.capita-libraries.co.uk/panlibus/2006/09/20/a_library_soa_e/ on August 27th, 2012.
The text was modified to update a link from http://www.cdlib.org/inside/news/presentations/rtennant/2005niso/ to http://roytennant.com/presentations/older/2005niso/ on November 13th, 2012.