| 摘要 |
A data processing system includes microcomputers 3, a host computer 5 with an associated modem bank 6 and file servers 10 connected in a token ring network 2. Generation and communication of documents is carried out by retrieval of programs from a general file server 10(a) and message and knowledge databases are set up in a communications file microcomputer 3 creates a record of all additional data stored server 10(b). To ensure that data is not lost, each in the fixed disk during a back-up period. Each general file server 10(a) includes a control circuit 12 arranged to poll each microcomputer 3 to retrieve additional data not already stored in the general file server 10(a), and at the end of each backup period each microcomputer 3 downloads additional data to a security file server 10(c) for transmission to a back-up tape drive 15. Each file server has an uninterruptible a power supply and writes data in parallel to a pair of disk drives. A network monitoring circuit 8 monitors errors in transmission of tokens which are not received. <IMAGE> |
