Nortel DMS-100 Series Maintenance Manual page 36

1-20 Maintenance overview
Note: When an office receives an initial software load with the new node
table management system, the CM gains control. The CM gains control of
compatible XPM node and terminal tables during the next scheduled
CDT/XPM node data audits. If the system takes an XPM out-of-service
(OOS), the CM does not assume control automatically. The audits must
convert an XPM to the CDT management system and align the CM with the
node tables. When this condition occurs, the CM assumes control.
The CM starts the audit request to an XPM with a VERTUPLE message.
The message has a parameter that identifies how the XPM must respond.
The XPM can send a message with specified tuples of data or a checksum of
the table. The system requests tuple data to supply the CM with the required
information to convert an XPM to CDT management control. If differences
are present between the active and inactive unit tables, the CM aligns to the
active unit table. The CM sets the XPM ISTb. After the system converts an
XPM to CDT, the system always requests a checksum of the table. The
system requests this checksum when the CDT audit runs.
The system uses checksums of node and port table data to verify
synchronization of XPM nodes under the CDT management system. To
calculate checksums, the system regenerates each tuple in the XPM table.
After the system formats a tuple, the system calculates the checksum for that
tuple. The system adds the calculated checksum to the table checksum for
that XPM. The system verifies the XPM checksums against corresponding
checksums that the CM generates. In both methods, when synchronization
does not occur, that unit is set ISTb. During the next audit cycle, the system
clears the ISTb condition if the unit checksum coincides with the CM
checksum.
The XPM node and port tables are compressed when the system takes both
units OOS and downloads new configuration data. This process allows the
CM to manage the node and port tables correctly.
The CM becomes more active in the maintenance of the node table integrity
in XPMs. When the CM becomes more active, the XPMs become less
active. The XPM must accept the CM data as the XPM receives the CM
data. The XPM cannot correct or adjust data.
297-8231-550 Standard 09.01 August 1998
The system adds a new XPM, but not during a one night process (ONP)
conversion. Nodes added during ONP are not new nodes. These nodes
must be in-service.