Conversation type
The APPC conversation type defines how data is passed on and retrieved from APPC verbs.
It is similar in concept to file blocking and affects both ends of the conversation.
APPC supports two types of conversations:
- Basic conversation
- This low-conversation allows programs to exchange data in a standardized format. This format is
a stream of data containing 2-byte length fields (referred to as LLs) that specify the amount of
data to follow before the next length field. The typical data pattern is:
Each grouping ofLL, data, LL, dataLL, datais referred to as a logical record. A basic conversation is used to send multiple segments with one verb and to receive maximum data with one verb. - Mapped conversation
- This high-conversation allows programs to exchange arbitrary data records in data formats approved by application programmers. One send verb results in one receive verb, and z/OS® and VTAM® handle the buffering.
Related Reading: For more information on basic and mapped conversations, see
- Systems Network Architecture: LU 6.2 Reference: Peer Protocols and
- Systems Network Architecture: Transaction Programmer's Reference Manual for LU Type 6.2