Expand Configuration and Management Manual (H06.21+, J06.10+)

Expand Modifiers
Expand Configuration and Management Manual — 529522-013
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NEXTSYS n
NEXTSYS n
Default: 255
Units: Not applicable
Range: 0 through 254
This path modifier is applicable to all Exp
and line types. This modifier specifies the
number of the system connected to the other end of the line. If you do not specify the
NEXTSYS modifier, it defaults to an invalid value (255), and an operator message
occurs during the initialization of this Expand line-handler process. The path will not be
operational until you alter the NEXTSYS modifier to a valid value using either the WAN
subsystem SCF ALTER DEVICE command or the Expand subsystem SCF ALTER
PATH command.
OSSPACE n
Default: 32767
Units: Words
Range: 3072 through 32767
This path modifier is applicable to all Expand line types. This modifier defines the
maximum buffer size for storing out-of-sequence (OOS) packets, in words. The OOS
buffer is in the data segment or the extended data segment. Networks that include
multi-line paths might require all Expand line-handler processes to have more than the
default buffer size for storing OOS packets.
OSTIMEOUT n
Default: 300 (3 seconds)
Units: 0.01 seconds
Range: 10 through 32767 (0.1 seconds through 5:27.67 minutes)
This path modifier is applicable to all Expand line types. This modifier specifies the
amount of time, in one-hundredth of a second increments, that out-of-sequence (OOS)
packets are held before they are discarded. For example, an OSTIMEOUT modifier
value of 300 is equal to 3 seconds. In general, the OSTIMEOUT modifier value should
be greater than the L2TIMEOUT modifier value and less than the L4TIMEOUT modifier
value.
The OSTIMEOUT modifier must be set to the same value for every Exp
and line-
handler process on every node in the network. If congestion control is enabled for any
system in the network, an OSTIMEOUT modifier value of at least 3 seconds is
recommended.
Note. The OSSPACE modifier is currently ignored. The amount of space allocated to out-of-
sequence (OOS) packets is limited by the OSTIMEOUT modifier and by the base size of the
line handler’s data segment. The OSSPACE modifier can be used in the future, in which case
its default, units, and range might be different. For this reason, the recommended setting for
OSSPACE is to not specify it, but to let the default be used.