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Network Router User Manual

ManualsBrandsSiemens ManualsNetwork RouterGENERAL INTERFACE FOR NETWORK APPLICATIONS V 4.0
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GINA V4.0 System Administrator Guide – September 2000 211
Glossary
Druck vom 24. 01.2001 17:01.06 fachwort
T-ORB
The Transaction-monitored Object Request Broker allows local objects to send
messages to remote objects with transaction monitoring. This means that not only the
(persistent) states of the object, but also the messages undergo transaction monitoring.
The sender does not have to worry about communication details.
time request
In the T-ORB procedure “time request”, a call is executed either at a certain time
(absolutely) or with a certain time delay (relatively). A client does not wait for the result
of a time request. Any events that may occur are thus discarded (see also →notifi-
cation).
transaction
A transaction is an operation which is executed in accordance with the all-or-nothing
rule. Transactions must comply with the ACID property (Atomicity, Consistency,
Isolation, Durability):
A transaction is atomic, i.e. it is executed without “interruption” as a result of individual
steps. A transaction changes an inconsistent state to a consistent state. Transactions
are isolated, i.e. any inconsistent interim states that may exist are not visible from the
outside. Their results are permanent, i.e. protected from errors.
see also →end of transaction
transaction-monitored request/call
A transaction-monitored request/call is carried out in a →transaction in accordance with
the all-or-nothing rule.
Transaction-monitored calls can occur in a distributed way under T-ORB. They then
form a →distributed transaction. A transaction-monitored call can be terminated with a
commit or a rollback.
transaction manager
see →transaction monitor
transaction monitor
A transaction monitor or transaction manager coordinates a number of →resource
managers and combines their →local transactions in a →distributed transaction
operation to form a →global transaction.
transient
In contrast to a →persistent object, the life span of a transient object is limited by the life
span of its process. Normal C++ objects are transient objects.