OSI/AS Management Programming Manual

ALTER SERVICE Command
Commands and Responses
056785 Tandem Computers Incorporated 5–85
ZCLASS
is the preferred transport protocol class to be used. The values for this field
are as follows:
ZOSI-VAL-CLASS-0
ZOSI-VAL-CLASS-1
ZOSI-VAL-CLASS-2
ZOSI-VAL-CLASS-3
ZOSI-VAL-CLASS-4
For LAN networks, and for X.25 networks when the Layer 3 attribute ZIP-X25-
SNDCF is set to ZSPI-VAL-TRUE, ZCLASS must be ZOSI-VAL-CLASS-4. The
ZCLASS value initially set by the OSI manager is null, but can be altered by
the values of ZNETTYPE and ZMULTIPLEX, as follows:
If ZNETTYPE is and ZMULTIPLEX is set to then ZCLASS is
A ZSPI-VAL-TRUE 2
A ZSPI-VAL-FALSE 0
B ZSPI-VAL-TRUE 3
B ZSPI-VAL-FALSE 1
C ZSPI-VAL-TRUE 4
C ZSPI-VAL-FALSE 4
ZALT-CLASS
is the alternative protocol class to be used if the class specified in ZCLASS is
not supported by the remote system. If ZCLASS has the value
ZOSI-VAL-CLASS-0, then ZALT-CLASS is not applicable. The values for this
field are the same as for ZCLASS.
The valid combinations of preferred protocol class and alternative protocol
class are as follows:
If the preferred class is an acceptable alternative class is
0 not applicable
1 0 or 1
2 0 or 2
3 0, 1, 2, or 3
4 0, 1, 2, 3, or 4.
If the preferred class and alternative class are the same, only that one class is
acceptable. The value initially set by the OSI manager is no alternative class.
ZTPDU-SIZE
is the maximum size (in bytes) of a transport protocol data unit (TPDU). The
acceptable values for this field are 128, 256, 512, 1024, 2048, 4096, and 8192
bytes. The values 4096 and 8192 are valid only when ZCLASS is 1, 2, 3, or 4.