Station-side apparatus of wavelength multiplexing PON system, wavelength and network address allotting method and program thereof

Abstract

To achieve a station-side apparatus of a wavelength multiplexing PON system, which is capable of saving the wavelength resource through automatically carrying out allotment of the wavelength and the network address to reduce the complicated work for the setting, and through dynamically allotting the wavelength without fixing it in advance. It is a station-side apparatus (OLT) of a wavelength multiplexing PON system that comprises a plurality of in-home apparatuses (ONUs). The station-side apparatus is connected to the in-home apparatuses via transmission paths including an optical multiplexing distributor, and executes allotment of the wavelength in response to wavelength allotment requests from the in-home apparatuses. The station-side apparatus comprises a wavelength/network address allotting device that is provided with a DHCP server in advance, which dynamically allots wavelength and network address to the in-home apparatus in response to the wavelength allotment request from the in-home apparatus.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates the structure of a PON system and signals transmitted therein according to an embodiment of the present invention, which describes the flow of downstream main signal;

FIG. 2 illustrates the structure of a PON system and signals transmitted therein according to an embodiment of the present invention, which describes the flow of upstream main signal;

FIG. 3 is a block diagram for showing the structure of an in-home apparatus according to the embodiment;

FIG. 4 is a block diagram for showing the structure of a station-side apparatus according to the embodiment;

FIG. 5 is a functional block diagram for showing the functions of the station-side apparatus shown in FIG. 4;

FIG. 6 is an illustration for describing an example of the wavelength allotment information that is stored in a memory of the station-side apparatus shown in FIG. 4;

FIG. 7 is an illustration for describing another example of the wavelength allotment information that is stored in the memory of the station-side apparatus shown in FIG. 4;

FIG. 8 is an illustration for describing still another example of the wavelength allotment information that is stored in the memory of the station-side apparatus shown in FIG. 4;

FIG. 9 is a flowchart for showing the operation of a control unit of the station-side apparatus shown in FIG. 4, when allotting the wavelength and the network address;

FIG. 10 is a flowchart for showing the operation of the in-home apparatus shown in FIG. 3, when allotting the wavelength and the network address;

FIG. 11 is an illustration for describing the flow of the signal when there is an allotment request from the in-home apparatus shown in FIG. 3;

FIG. 12 is an illustration for describing the flow of the signal in the station-side apparatus, when transmitting the signal in response to the allotment request of the in-home apparatus shown in FIG. 3;

FIG. 13 is an illustration for describing the flow of the signal when there is a collision in the allotment requests from the in-home apparatuses shown in FIG. 3;

FIG. 14 is an illustration for describing the flow of the signal in the station-side apparatus, when there is a collision in the allotment requests from the in-home apparatuses shown in FIG. 3;

FIG. 15 illustrates a typical format of a DHCP message;

FIG. 16 is an illustration for describing an example of the DHCP message format in which a subnet mask and the DHCP message type are stored in an OPTION field;

FIG. 17 is an illustration for describing a format of the DHCP message when a single network address and a wavelength each for the upstream and downstream are allotted to a single in-home apparatus;

FIG. 18 illustrates a format of the DHCP message when a wavelength is allotted for each application;

FIG. 19 illustrates the basic structure of a conventional PON system and signals transmitted therein, which describes the flow of the downstream signal;

FIG. 20 illustrates the basic structure of a conventional PON system and signals transmitted therein, which describes the flow of the upstream signal;

FIG. 21 illustrates the basic structure of a conventional wavelength division multiplexing PON system and signals transmitted therein, which describes the flow of the downstream multiplexed signal;

FIG. 22 illustrates the basic structure of a conventional wavelength division multiplexing PON system and signals transmitted therein, which describes the flow of the upstream multiplexed signal;

FIG. 23 is a block diagram for showing the structure of a conventional in-home apparatus; and

FIG. 24 is a block diagram for showing the structure of a conventional station-side apparatus.

Claims

1. A station-side apparatus (OLT) of a wavelength multiplexing PON system, which executes allotment of wavelengths in response to wavelength allotment requests from a plurality of in-home apparatuses (ONUs), the apparatus comprising a wavelength/network address allotting device that is provided with a DHCP server in advance, which dynamically allots a wavelength and a network address to the in-home apparatus in response to the wavelength allotment request from the in-home apparatus.

2. The station-side apparatus of a wavelength multiplexing PON system as claimed in claim 1, wherein the wavelength/network address allotting device comprises a wavelength/network address storing device for storing a plurality of wavelengths and network addresses to be allotted, and has a function of calling the wavelength and the network address from the wavelength/network address storing device according to an allotment request signal from the in-home apparatus, and transmitting the wavelength and the network address as an allotment signal when starting up the system (collecting and returning the allotted wavelength and the network address to the wavelength/network address storing device when closing the system).

3. The station-side apparatus of a wavelength multiplexing PON system as claimed in claim 2, comprising: an allotment request signal receiving device for receiving the allotment request signal as a first wavelength control signal that is common to the plurality of in-home apparatuses; and an allotment signal transmitting device for transmitting the allotment signal as a second wavelength control signal that is common to the plurality of in-home apparatuses.

4. The station-side apparatus of a wavelength multiplexing PON system as claimed in claim 3, comprising: a collision detecting device for detecting with the first wavelength control signal that the allotment request signals from the plurality of in-home apparatuses are collided; and a collision signal transmitting device for transmitting a collision signal commonly to the plurality of in-home apparatuses by the second wavelength control signal when the collision detecting device detects a collision.

5. The station-side apparatus of a wavelength multiplexing PON system as claimed in claim 1, wherein the wavelength/network address allotting device has a function of allotting a different wavelength and network address for each of work contents of the in-home apparatus.

6. A wavelength and network address allotting method which executes allotment of wavelengths by a station-side apparatus (OLT) of a wavelength multiplexing PON system in response to wavelength allotment requests from a plurality of in-home apparatuses (ONUs), the method comprising steps of: an allotment request receiving step which receives the wavelength allotment request from the in-home apparatus;a wavelength allotting step which dynamically allots the wavelength and the network addresses to the in-home apparatus in response to the received allotment request by using a DHCP server that is provided in advance; andan allotment wavelength transmitting step which transmits the allotted wavelength and the network address to the in-home apparatus that has transmitted the allotment request.

7. A wavelength and network address allotting method which executes allotment of wavelengths by a station-side apparatus (OLT) of a wavelength multiplexing PON system in response to wavelength allotment requests from a plurality of in-home apparatuses (ONUs), the method comprising steps of: an allotment request receiving step which, when starting up the wavelength multiplexing PON system, receives the allotment requests from the in-home apparatuses by using a first wavelength control signal that is common to the plurality of in-home apparatuses;a collision detecting step which detects a collision between the allotment requests that are transmitted from the plurality of in-home apparatuses;a readout step which reads out the wavelength and the network address to be allotted from a wavelength/network address storing device, when a collision is not detected in the collision detecting step; andan allotment signal transmitting step which transmits and allots the wavelength and the network address read out in the readout step to the in-home apparatus as an allotment signal by using a second wavelength control signal that is common to the plurality of in-home apparatuses.

8. The wavelength and network address allotting method as claimed in claim 7, comprising a collision signal transmitting step which transmits a common collision signal to the plurality of in-home apparatuses by using a second wavelength control signal, when a collision is detected in the collision detecting step.

9. A wavelength and network address allotting program for allowing a computer, which constitutes a station-side apparatus of a wavelength multiplexing PON system that is constituted with a plurality of in-home apparatuses and the station-side apparatus that is connected to the plurality of in-home apparatuses via transmission paths including an optical multiplexing distributor, to execute: an allotment request reception processing function which performs reception processing of a wavelength allotment request from the in-home apparatus;a wavelength allotment processing function which dynamically allots the wavelength and the network address to the in-home apparatus in response to the reception-processed allotment request by using a DHCP server that is provided in advance; andan allotted wavelength transmission processing function which performs transmission processing of the allotted wavelength and the network address to the in-home apparatus that has transmitted the allotment request.

10. A wavelength and network address allotting program for allowing a computer, which constitutes a station-side apparatus of a wavelength multiplexing PON system that is constituted with a plurality of in-home apparatuses and the station-side apparatus that is connected to the plurality of in-home apparatuses via transmission paths including an optical multiplexing distributor, to execute: an allotment request reception processing function which, when starting up the wavelength multiplexing PON system, receives the allotment requests transmitted from the in-home apparatuses by using a first wavelength control signal that is common to the plurality of in-home apparatuses;a collision information processing function which, when a collision is detected between the allotment requests transmitted from the plurality of in-home apparatuses, performs processing of information on the detected collision;a readout processing function which reads out the wavelength and the network address to be allotted from a wavelength/network address storing device, when a collision between the allotment requests is not detected; andan allotment signal transmission processing function which transmits and allots the wavelength and the network address read out in the readout step to the in-home apparatus as an allotment signal by using a second wavelength control signal that is common to the plurality of in-home apparatuses.