Migration assist device, migration method and optical access system

A transition method performed by a transition assistance device that assists device replacement in an optical access system including:

• a transition source subscriber line terminal station device before device replacement, the transition source subscriber line terminal station device communicating with a higher-level device and one or more subscriber line terminal devices;
• and a transition destination subscriber line terminal station device that is a device replacement destination, wherein
• the transition assistance device includes a first member, and a second member that is movable,
• the first member includes a first port for connecting to the transition source subscriber line terminal station device, and a second port for connecting to the transition destination subscriber line terminal station device,
• the second member includes a third port for connecting to the one or more subscriber line terminal devices connected to the transition source subscriber line terminal station device, and
• at a start of the device replacement, the transition assistance device is not connected to the transition destination subscriber line terminal station device via the second port, and the first port and the third port are connected to each other via a connection line, the transition method comprising:
• cutting the connection line connecting the first port and the third port to each other after the transition assistance device is connected to the transition destination subscriber line terminal station device via the second port;
• moving the second member after the connection line is cut;
• and
• connecting the second port and the third port to each other with connection lines after movement of the second member.

An optical access system including:

• a transition source subscriber line terminal station device before device replacement, the transition source subscriber line terminal station device communicating with a higher-level device and one or more subscriber line terminal devices;
• and a transition destination subscriber line terminal station device that is a device replacement destination,
• the optical access system comprising
• a transition assistance device that assists device replacement between the transition destination subscriber line terminal station device and the one or more subscriber line terminal devices,
• wherein
• the transition assistance device includes:
• a first member, and a second member that is movable, wherein
• the first member includes a first port for connecting to the transition source subscriber line terminal station device, and a second port for connecting to the transition destination subscriber line terminal station device,
• the second member includes a third port for connecting to the one or more subscriber line terminal devices connected to the transition source subscriber line terminal station device, and
• at a start of the device replacement, the transition assistance device is not connected to the transition destination subscriber line terminal station device via the second port, and the first port and the third port are connected to each other via a connection line;
• a cutting unit that cuts the connection line connecting the first port and the third port to each other after the transition assistance device is connected to the transition destination subscriber line terminal station device via the second port;
• a movement control unit that moves the second member after the connection line is cut by the cutting unit;
• and
• a connection unit that connects the second port and the third port to each other with connection lines after movement of the second member, and
• the transition destination subscriber line terminal station device includes:
• a higher-level device side transition unit including a higher-level port for connecting to the higher-level device and a first transition port that transfers data transferred from the higher-level device to the transition source subscriber line terminal station device;
• a transfer table setting unit that changes a setting of a transfer table in which a port at which data is received, a destination of the data, and a port of a transfer destination of the data are associated with each other;
• and
• a transfer control unit that performs data transfer to the transition source subscriber line terminal station device via at least the first transition port in accordance with the transfer table.