A mode is associated with LU-LU pairs, and determines session properties for that pair. For independent APPC LU sessions, the Parallel Session Limit parameter is of particular importance, as this limit determines the number of simultaneous conversations that a session can support. If you plan to use a remote APPC LU that supports parallel sessions, it can only be used with a mode whose parallel session limit has a value greater than 1. Also, parallel sessions are not possible over DFT-type physical connections to the host.
Table 6.1 lists the modes supplied with SNA Server and describes the scenarios in which each mode can be used.
Table 6.1 SNA Server-supplied modes.
| Mode name | Suitability |
| #BATCH | Batch-oriented sessions |
| #BATCHSC | Batch-oriented sessions that employ a minimal level of routing security |
| BLANK | Sessions using a default node name, encoded as eight blank EBCDIC spaces in a BIND APPC command |
| #INTER | Interactive sessions |
| #INTERSC | Interactive sessions that employ a minimal level of routing security |
| QPCSUPP | All sessions with an AS/400 computer |
| QSERVER | Database connectivity with the ODBC host database drivers provided with SNA Server |