OSI/AS Management Programming Manual

ALTER SERVICE Command
Commands and Responses
5–86 056785 Tandem Computers Incorporated
For X.25 subnetworks: OSI/TS will adjust the value of ZTPDU-SIZE to not
exceed the value of the X25AM SYSGEN attribute MAXIOSIZE. The value
initially set by the OSI manager is 512 bytes.
ZXSUM
specifies whether the checksum field is added to each TPDU. This field
applies only to protocol class 4 communication. If this field is set to
ZSPI-VAL-TRUE, the checksum field is added; if it is set to ZSPI-VAL-FALSE,
the checksum is not added. The value initially set by the OSI manager is ZSPI-
VAL-FALSE.
ZEXT-FRMT
specifies whether the credit and sequence number of the TPDUs should be in
extended format. This field applies only to protocol class 2, 3, or 4
communication. If this field is set to ZSPI-VAL-TRUE, the extended format is
used; if it is set to ZSPI-VAL-FALSE, the normal format is used. The value
initially set by the OSI manager is ZSPI-VAL-FALSE.
ZMULTIPLEX
specifies whether multiple outgoing transport connections are allowed to be
mapped onto one network connection. This field applies only to protocol class
2, 3, or 4 communication over a connection-mode network service (CONS;
X.25 is an example). If this field is set to ZSPI-VAL-TRUE, multiplexing is
attempted; if it is set to ZSPI-VAL-FALSE, multiplexing is not attempted. The
value initially set by the OSI manager is ZSPI-VAL-FALSE.
Multiplexing requires that two or more transport connections have the same
local and remote NSAP addresses; have ZCLASS set to 2, 3, or 4; and have
ZMULTIPLEX set to ZSPI-VAL-TRUE. If these conditions are met, the
maximum number of outgoing transport connections that can be multiplexed
is determined by the Layer 3 SERVICE attribute ZX25NCON-MULTIPLEX.
ZREXMIT-TIMEOUT
is the maximum amount of time that the transport entity should wait for an
acknowledgment before resending the TPDU. This field applies only to
protocol class 4 communication. The waiting time is expressed in hundredths
of a second (0.01 seconds per increment). The values range from 100 (1
second) through 3000 (30 seconds). The value initially set by the OSI manager
is 1000 (10 seconds).
ZREF-TIMEOUT
is the maximum amount of time that the transport entity should wait before
reusing any reference or sequence number. The waiting time is expressed in
hundredths of a second (0.01 seconds per increment). The values range from
300 (3 seconds) through 18000 (180 seconds). The value initially set by the OSI
manager is 3000 (30 seconds).