IBM Domino servers and Notes clients identify NSF files by their Replica IDs, and keep replicated files synchronized by bi-directionally exchanging data, metadata, and application logic and design. There are options available to define what meta-data replicates, or specifically exclude certain meta data from replicating. Replication between two servers, or between a client and a server, can occur over a network or a point-to-point modem connection. Replication between servers may occur at intervals according to a defined schedule, in near-real-time when triggered by data changes in server clusters, or when triggered by an administrator or program.