Transmission device and upgrade method thereof

Abstract

A transmission device comprises a plurality of types of exchangeable duplexed interface cards on a receiving side and a transmitting side; an STS or VC switch card having functions of setting a signal route between the interface cards by an STS or VC on the receiving side and the transmitting side and of switching over a duplexed system in at least one of an interface card unit, a line unit, an STS path unit and a VC path unit; and a monitoring portion controlling the STS switch card and the transmitting side interface cards upon switching, and setting a signal route. For upgrading the transmission device, when an interface card is upgraded in service by increasing a transmission capacity of the duplexed already-existing interface cards, an interface card on a standby side is exchanged with an interface card having a larger capacity, the monitoring portion performs the same setting as that of an interface card on an active side, switches over the interface card on the standby side to the active side as well as the interface card on the active side to the standby side, by controlling the STS or VC switch card and a switch portion of the transmitting side interface card, and exchanges the interface card with an interface card having the capacity.

Dependencies are inferred from the claim text.