APPC (LUTYPE6.2) links and parallel sessions

For APPC, the sessions are grouped into modesets. Each modeset is defined in the macro method with a TYPE=MODESET macro, and the equivalent in RDO is one SESSIONS definition on the CSD file.

The ISC link is defined by:
DFHTCT TYPE=SYSTEM,SYSIDNT=ssss,ACCMETH=VTAM,TRMTYPE=LUTYPE62
The parallel sessions for the link are defined collectively by:
DFHTCT TYPE=MODESET,MODENAM=mmmmmmmm,SYSIDNT=ssss,
       MAXSESS=(m1,m2)
DFHCSDUP MIGRATE produces a CONNECTION definition from the TYPE=SYSTEM macro:
DEFINE CONNECTION(ssss) ACCESSMETHOD(VTAM) PROTOCOL(APPC)
and a SESSIONS definition from the TYPE=MODESET macro:
DEFINE SESSIONS(xxxxxxx)  CONNECTION(ssss) PROTOCOL(APPC)
       MAXIMUM(m1,m2)     MODENAME(mmmmmmmm)
The SESSIONS name xxxxxxxx is derived from the old SYSIDNT value concatenated with a 3-character identifier generated using the same algorithm as the old macro. For example, for SYSIDNT=SYS1:
MODESET1: MAXSESS=4  gives SESSIONS(SYS1AAC) (starting count)
MODESET2: MAXSESS=2  gives SESSIONS(SYS1AAG) (MODESET1 + 4)
MODESET3: MAXSESS=3  gives SESSIONS(SYS1AAI) (MODESET2 + 2)

The MODENAME name mmmmmmmm is the macro MODENAM value.