Optical crossconnect system and its controller and method

• US 20020197001A1
• Filed: 06/19/2002
• Published: 12/26/2002
• Est. Priority Date: 06/25/2001
• Status: Abandoned Application

• Current Assignee: KDDI Corporation
• Original Assignee: KDDI Corporation
• Inventors: Tanaka, Hideaki, Otani, Tomohiro, Suzuki, Masatoshi, Hayashi, Michiaki
• Application Number:
  US10/176,000
• Publication Number:
  US 20020197001A1
• Time in Patent Office: Days
• US Class Current: 385/17
• CPC Class Codes: G02B 6/356 in an optical cross-connect device, e.g. routing and switching aspects of interconnecting different paths propagating different wavelengths to (re)configure the various input and output links switching polarized beams G02B6/3594; power equalizers G02B6/356 and G02B6/3594; path selecting means H04Q11/0001
• CPC Class Codes: G02B 6/3562 Switch of the bypass type, i.e. enabling a change of path in a network, e.g. to bypass a failed element in the network
• CPC Class Codes: H04Q 11/0005 Switch and router aspects
• CPC Class Codes: H04Q 2011/0024 using space switching
• CPC Class Codes: H04Q 2011/0039 Electrical control
• CPC Class Codes: H04Q 2011/0043 Fault tolerance
• CPC Class Codes: H04Q 2011/0056 Clos

Abstract

An optical crossconnect system comprises an input stage including a plurality of input matrix switches, each having a plurality of input ports and a plurality of output ports, an output stage including a plurality of output matrix switches, each having a plurality of input ports and a plurality of output ports, and an intermediate stage including a plurality of intermediate matrix switches, each having a plurality of input ports and a plurality of output ports. Each input port of each intermediate matrix switch connects to an output port which corresponds to the intermediate matrix switch, at an input matrix switch corresponding to the input port in the plurality of input matrix switches. Each output port of each intermediate matrix switch connects to an input port, which corresponds to the intermediate matrix switch, at an output matrix switch corresponding to the output port in the plurality of output matrix switches. At least one output port nearest to the input side in each of the plurality of input matrix switches is reserved for protection and at least one input port nearest to the output side in each of the plurality of output matrix switches is reserved for protection.

Claims

1. An optical crossconnect system comprising:

an input stage including a plurality of input matrix switches, each having a plurality of input ports and a plurality of output ports;

an output stage including a plurality of output matrix switches, each having a plurality of input ports and a plurality of output ports; and

an intermediate stage including a plurality of intermediate matrix switches, each having a plurality of input ports and a plurality of output ports;

wherein each input port of each intermediate matrix switch connects to an output port which corresponds to the intermediate matrix switch, at an input matrix switch corresponding to the input port in the plurality of input matrix switches;

each output port of each intermediate matrix switch connects to an input port, which corresponds to the intermediate matrix switch, at an output matrix switch corresponding to the output port in the plurality of output matrix switches; and

at least one output port nearest to the input side in each of the plurality of input matrix switches is reserved for protection and at least one input port nearest to the output side in each of the plurality of output matrix switches is reserved for protection.

2. The crossconnect system of claim 1 further comprising:

a fault table to store whether any fault exists in the input matrix switch, the output matrix switch, and the intermediate matrix switch;

a working route table to store working routes; and

a controller to refer to the fault table and working route table according to a fault occurrence in any of the input matrix switch, the output matrix switch, and the intermediate matrix switch and to set a new route which bypasses the fault part.

3. A controller to control routes of an optical crossconnect apparatus comprising an input stage having a plurality of input matrix switches, an output stage having a plurality of output matrix switches, and a plurality of intermediate matrix switches including at least one reserved intermediate matrix switch, the controller comprising:

a fault table to store whether any fault exists and where a fault locates in the plurality of input matrix switches, the plurality of output matrix switches, and the plurality of intermediate matrix switches;

a working route table to store working routes of the optical crossconnect apparatus;

a fault location determining apparatuses to determine a fault occurrence location; and

a route controller to set a new route on a fault occurrence between an input port and an output port of the optical crossconnect apparatus whose route is blocked by the fault;

wherein the route controller comprising;

first route controlling mode to refer the fault table and the working route table when a fault occurs in at least one of the input and output stages, to make a list of intermediate matrix switches which can newly connect between an input port and an output port of the optical crossconnect apparatus whose route is blocked by the fault from the intermediate matrix switches except for the reserved intermediate matrix switch, to determine an intermediate matrix switch to be used from the list, and to construct a new route;

second route controlling mode to refer the fault table and the working route table when a fault occurs only in the intermediate stage, to make a list of intermediate matrix switches which can newly connect an input port and an output port of the optical crossconnect apparatus whose route is blocked by the fault from the intermediate matrix switches except for the intermediate matrix switch having the fault and the reserved intermediate matrix switch, to determine an inter mediate matrix switch to be used from the list, and to construct a new route;

third route controlling mode to refer the fault table and the working route table when a fault occurs in both input stage and the intermediate stage and a fault occurs in both output stage and intermediate stage, and to construct a new route between an input port and an output port of the optical crossconnect apparatus whose route is blocked by the fault using the reserved intermediate matrix switch in the intermediate matrix switches.

4. The controller of claim 3 wherein the route controller performs a route control using the first route controlling mode when no reserved intermediate matrix switch is available in the third route controlling mode.

5. The controller of claim 3 wherein the route controller performs construction of a new route in order of the first, third, and second route controlling modes.

6. The controller of claim 3 wherein each input port of each intermediate matrix switch connects to an output port, which corresponds to the intermediate matrix switch, at an input matrix switch corresponding to the input port in the plurality of input matrix switches;

each output port of each intermediate matrix switch connects to an input port, which corresponds to the intermediate matrix switch, at an output matrix switch corresponding to the output port in the plurality of output matrix switch; and

at least one output port nearest to an input side in each of the plurality of input matrix switch is reserved for protection and at least one input port nearest to an output side in each of the plurality of output matrix switches is reserved for protection.

7. A controlling method to control an optical crossconnect apparatus comprising an input stage having a plurality of input matrix switches, an output stage having a plurality of output matrix switches, and an intermediate stage having a plurality of intermediate matrix switches including at least one reserved intermediate matrix switches, the method comprising:

a fault storing step to store in a fault table whether and where a fault exists in the plurality of input matrix switches, the plurality of output matrix switches, and the plurality of intermediate matrix switches;

an working route storing step to store in a working route table about working route of the optical crossconnect apparatus;

a fault location determining step to determine a fault occurrence location;

a first route controlling step to refer the fault table and the working route table when any fault occurs in at least one of the input and output stages, to make a list of intermediate matrix switches which can newly connect between an input port and an output port of the optical crossconnect apparatus whose route is blocked by the fault, to determine an intermediate matrix switch to be used from the list, and to construct a new route;

a second route controlling step to refer to the fault table and the working route table when a fault occurs only in the intermediate stage, to make a list of intermediate matrix switches which can connect between an input port and an output port of the optical crossconnect apparatus whose route is blocked by the fault from the intermediate matrix switches except for the intermediate matrix switch having the fault and the reserved intermediate matrix switch, to determine an intermediate matrix switch to be used from the list, and to construct a new route; and

a third route controlling step to refer to the fault table and the working route table when a fault occurs in both input stage and intermediate stage and a fault occurs in both output stage and intermediate stage, and to construct a new route between an input port and an output port of the optical crossconnect apparatus whose route is blocked by the fault using the reserved intermediate matrix switch in the intermediate matrix switches.

8. The controlling method of an optical crossconnect apparatus of claim 7 further comprising a step to perform the first route controlling step when no reserved intermediate matrix switch is available in the third route controlling step.

9. The controlling method of an optical crossconnect apparatus of claim 7 to perform construction of a new route in order of the first, third, and second route controlling steps.

10. The controlling method of an optical crossconnect apparatus of claim 7 wherein:

each input port of each intermediate matrix switch connects to an output port, which corresponds to the intermediate matrix switch, at an input matrix switch corresponding to the input port in the plurality of input matrix switches;

each output port of each intermediate matrix switch connects to an input port, which corresponds to the intermediate matrix switch, at an output matrix switch corresponding to the output port in the plurality of output matrix switches; and

at least one output port nearest to an input side in each of the plurality of input matrix switches is reserved for protection and at least one input port nearest to an output side in each of the plurality of output matrix switches is reserved for protection.