7-99
ATM Switch Router Software Configuration Guide
OL-7396-01
Chapter 7
Configuring Virtual Connections
Input Translation Table Management
On initial configuration of the
atm input-xlate-table autominblock
command, ITT memory may
already be somewhat fragmented due to previous commands.
The effect of the fragmentation can be minimized by configuring, when first using the VPI, a
cross-connect that uses the maximum VCI on a VPI. Note, however, that this should not be considered
the best everyday practice; in general, for effective automatic determination of minimum block size on
a VPI, a PVC should be configured by using the planned maximum VCI on a VPI.
When autominblock mode is disabled (via use of the
no
form of the command), all previously entered
minblock configuration commands entered without the
force
keyword are lost.
Unless one of the
atm
input-xlate-table
configuration commands is entered, the system operates as it
did prior to these enhancements.
Whether or not the
atm input-xlate-table autominblock
configuration is in effect, the user can
configure
atm input-xlate-table minblock
for interface/VPIs, (if the
force
keyword is used). The affect
of the
minblock
command in the various situations in which it can be used is shown in
Table 7-5
:
Table 7-5
autominblock-force minblock Interaction Matrix
autominblock
mode enabled
force minblock with
command keyword used
Effect
True
True
Command accepted; value
rounded up and used as
block-size hint, value not
overridden by automatic
analysis; value will be
nvgened.
True
False
Command accepted; value
rounded up used as a floor for
block-size hint; value may be
overridden by automatic
analysis; value not necessarily
nvgened.
False
True
Command accepted; value
rounded up and used as
block-size hint; value will be
nvgened
False
False
Command not accepted.
