OpenLink Product Overview Express Edition Drivers OpenLink's Express Edition drivers are similar to OpenLink's Single-Tier drivers. They require a single installation on the machine that hosts the client application. Whereas Single-Tier drivers establish connectivity via the database native client or use of the database wire protocol, Express Edition drivers establish connectivity through use of 3rd-party, native JDBC drivers that pre-exist on the client machine.Express Edition drivers are lightweight, low cost drivers that are suitable for environments wherein performance is not a critical issue. Likewise, Express Edition drivers should not be advanced when there is a need for exceptional stability or security. Single-Tier drivers provide better performance, and Multi-Tier drivers provide the most reliable stability and advanced security features.