The Distributed Relational Database Architecture (DRDA) is an open architecture that allows disparate applications and database systems to communicate and interoperate. DRDA communications can occur over multiple network transport protocols.
Each level of DRDA implementations has increased the level of support for distributed computing. Along with other significant enhancements, DRDA Level 3 introduced support for direct TCP/IP connections. DB2 hosts that support DRDA Level 3 or later can use either of the following network protocols to communicate with client computers:
SNA LU 6.2, which exchanges commands and data as SNA LU 6.2 conversations.
TCP/IP, which uses Distributed Data Management (DDM) commands to send requests and replies between the requester and the database server.
StarPipes for Windows can transfer the incoming messages as SNA-APPC conversations to DB2, or allow the TCP/IP messages to flow directly to the DB2 host unchanged. The DB2 system must support DRDA over TCP/IP to receive TCP/IP messages unchanged. (Refer to System Requirements for a list of the DB2 versions that support native TCP/IP connections.)
Be sure to review the topic, DRDA Security Flows, if you want to allow StarPipes to pass encrypted user IDs and passwords to a DB2 host.