Introduction to OTMA

IMS Open Transaction Manager Access (OTMA) is a transaction-based, connectionless client/server protocol.

Though easily generalized, its implementation is specific to IMS in a z/OS® sysplex environment. The domain of the protocol is restricted to the domain of the z/OS cross-system coupling facility (XCF).

OTMA addresses the problem of connecting a client to a server so that the client can support a large network, or a large number of sessions, while maintaining high performance.

Other solutions available today use network-based protocols, such as Systems Network Architecture (SNA). These protocols require a great amount of overhead because they are not transaction based.