| 摘要 |
PROBLEM TO BE SOLVED: To substitute another address translation router when any operation abnormality occurs at an address translation router. SOLUTION: Plural address translation routers 1 exist and an address table 11 therefor is backed up in a backup device 2. When the operation abnormality of any address translation router is detected by an address translation router monitoring part 22, by transferring the address translation router, where the operation abnormality occurs, to the other address translation router, the backup device 2 can perform the substitution of the address translation router where the operational abnormality occurs. |
