CDL Depends on Control
In order to properly implement CDL, a library must have the ability to restrict access to digital files in two primary ways: the CDL system must restrict concurrent usage (how many copies are open at a time) and must enforce expiration (how long each copy can remain open).
- Restrict the number of open copies, to maintain "Owned to Loaned" ratio
- Force-close documents when the loan period expires
- Log usage data while respecting user privacy