| 摘要 |
PROBLEM TO BE SOLVED: To realize a protection system for facilitating countermeasures to any communication abnormality which is made valid to an optical network(PON) in which simplexed equipment and duplexed equipment is allowed to coexist. SOLUTION: This optical network in which simplexed equipment and duplexed equipment 11(0) and 11(1) is allowed to coexist is provided with transmission path switching means 12 and 22, so that different transmission paths defined on a logical layer in a higher order than that of a physical layer forming an optical transmission system 2 can be individually assigned to the present system and preliminary system of the multiplexed equipment. This optical network is also provided with a subscriber side transmission path converting means 13 for converting the transmission path into a specific transmission path assigned to the downstream side, and a station side transmission path converting means 23 for converting the transmission path into a specific transmission path assigned to an upstream side. |
