Replication means the possibility to synchronize copies of databases located on different servers, or on the server and the client computer. Each field of each document includes a time mark, and the replication is conducted using the last time value. As the replication is carried out at the separate fields level, it allows you to avoid picking out a master replica and other restrictions peculiar to replication in relational databases.

In combination with record level security, replication provides unique flexibility in developing distributed systems, for example, for connecting remote offices and subdivisions in the other cities. Owing to the combination of these features, Lotus Notes enables access to all application functions without connecting to a server. A user makes changes to the local replica of the database and then replicates them to the server, when connection with the server is set. Importantly, even if an outside user finds a way to make changes to the local replica that are not matching up with the application's business logic, it will be impossible for him to replicate those changes to the server, assuming the security was designed properly.

ERP Systems
The most successful ERP (Enterprise Resource Planning) systems are developed on top of relational DBMSs, because relational DBMSs are capable of effective processing of complex queries. A typical ERP system, such as SAP/R3, operates through a centralized server and a centralized data warehouse. Access control to this data is centralized as well. An R3 user can see all application data, though his ability to modify the data is restricted by the business logic. As a rule, to divide the whole R3 into several small parts or independent subdivisions without destroying the integrity proves to be a difficult task.

Possible integration scenarios
Based on the information above, we could draw a conclusion that Notes and ERP are not competing systems, but rather complementary ones. One of the possible integration strategies could be to use Notes as an environment for collecting and entering data for the ERP system. Primary data entry into the system could represent proposals of subdivisions and even employees, or it could be the reports on current performance.