英语翻译

英语翻译
The three methods proposed in this paper much differ from each
other in time required for the additional operations of database
migration and checkpoint.As for the additional operations of
database migration,the CS method requires the longest time
and the LS method is the next.Especially,since the CS method
writes the backup to disk at every migration,this method requires
much longer time than other two methods.On the other
hand,as for the additional operations of checkpoint,the NS
method requires longest time and the LS method is the next.
Especially,since the NS method requires many message transmissions,
the method requires much longer time than other two
methods.In a practical environment,we should select the optimal
method among them according to the features of the system.
Here,we estimate the extra processing time caused by each
method and we perform a simple performance evaluation.From
the result,we show the optimal method for a given system enbironment.
To formulate the processing time of each method,
we use the parameters shown in Table 1.The parameters about
oata transmission are based on the prospect of the near future
distributed systems with world-wide scale.First,the value of
the propagation delay,d,represents the world-wide ATM-VLAN.