A large segment in the ebook market that Adobe Content Server (ACS) serves is in the book lending segment: libraries. A set of DRM permissions is used in ACS to facilitate the concept of ebook lending, which fortunately, emulates closely the familiar lending of a physical book in a library. When I go to borrow a book from a brick-and-mortal library, I know that, 1) the library has limited copies of the book that I am interested in; 2) if I borrow a book, I need to return it by a certain date (expiration time); 3) I can return the book before the expiration date (early return); and 4) the library probably has a limit on how many books I can borrow at any given time (I have never tried to borrow a really large number of books at once, so I don’t know whether there is such a limit, and if so, what it is.)
ACS emulates these properties closely with four permission settings that can be set; three of which are properties of an ebook: 1) expiration time, 2) returnable property, 3) the number of copies a book can be loaned out; and lastly, 4) as a property of the library (an ACS distributor), the maximum number of books a single user can borrow at any given time.
The expiration time on the ACS Read permission can be set to expire either after a certain period of time after a book is downloaded or at a specific date. For loaned books, it is more common to set the expiration time to a specific period of time, such as 14 or 21 days. But you can set this to any length of time.
There are two permissions settings grouped under the ACS “Loan” permission. It is important to understand that this set of permissions is what distinguishes a “loan” book, not the expiration time.
The “Returnable Loan” property is a true/false permission property. Setting this permission enables the feature commonly known as “Early Return” which some reader applications support. When this is supported in a reader application, a user can “return” an ebook before it expires. After a book is returned, the book becomes unreadable in the reader application, and the count of the available copies on the server side goes up by one, to permit subsequent lending of the same book to another user.
In addition to the returnable flag, you can also set the maximum concurrent copies of a book that can be loaded out at any given time. Download of a loaned book decreases this number by one, and an early return of the book increases this number by one. Note that it often takes time for ACS to register an early return, so you may not see a change in the number of copies available for loan as soon as an early return occurs. If this number is set to -1, or left blank, when you first add the loan settings, it means that there is no limit.
These are the basics of setting up ebooks for loans. Let’s now use this to address some of the commonly asked questions.
How to add loan permissions in ACS?
A common way to do this is to add a distribution rights type. You can name it “Loan” or something else. A book can have one or many sets of distribution rights. If you don’t need other kind of permissions, you can have just one for the loan. To add a distribution rights type, use “+” next to the DISTRIBUTION RIGHTS.
Be sure to use the name you assigned for this distribution rights type in the download link that you send to users to invoke the right set of permissions.
How to make “borrow” button work in ACS sample bookstore?
The ACS sample bookstore comes with two buttons that mimick the process of buying or borrowing a book from the store. One is named “Purchase”, and the other one “Borrow”. To use the “Borrow” button, the distribution rights type must be named “Loan.” It doesn’t matter what specific loan permission settings you use.
Can a book have loan permission without expiration?
Generally, it wouldn’t make sense to loan books without any expiration. However, technically, the expiration permission can be independently set so it is possible to set loan settings without an expiration time.
Can a book have expiration date without loan settings?
Yes, the expiration restricts how long a user can read the book, and you can set this permission without setting the loan property. For example, you may want to build a business model that ebooks are valid for a certain period of time, for example, textbooks for teachers and students that you want to be valid for a year. Since this is not a loan in the sense that you don’t need to control the number of copies out on loan, and there is no reason for early return, you only need to set the expiration date without adding those loan permissions.
What is the difference between an expiring book and a loan book?
Because expiration and loan settings are not tied to each other, you can have books set to expire but not be returnable as a loaned item. An expiring book doesn’t have to have the loan properties. Conversely, a loaned book does not have to have an expiration date. In practice, they usually go hand in hand.
What is “MAX LOAN COUNT” in “DISTRIBUTOR INFO” tab?
One of the distributor properties shown in ACS admin console for a selected distributor is “MAX LOAN COUNT.” This can have a value of 1 to 50,000. The value controls how many loaned books a single user can have at any given time. Note that this is the count for a single user. There is no limit in the total number of books that a distributor can sell or lend to all users.
I think this covers about all the basics specifically related to ACS loaned ebooks. If you have any questions, please comment to this post or email us at email@example.com.