Storage area network extension over passive optical networks using parallel signal detection

• US 8,200,086 B2
• Filed: 03/07/2008
• Issued: 06/12/2012
• Est. Priority Date: 09/11/2007
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Laboratories America Inc (NEC Corporation)
• Inventors: Luo, Yuanqiu, Yin, Si, Yu, Jianjun, Zong, Lei
• Primary Examiner(s): Curs, Nathan
• Assistant Examiner(s): NGO, TANYA T
• Application Number:
  US12/044,417
• Publication Number:
  US 20090067839A1
• Time in Patent Office: 1,558 Days
• Field of Search: 398/76, 398/43, 398/58
• US Class Current: 398/58
• CPC Class Codes: H04J 14/0226 Fixed carrier allocation, e.g. according to service
• CPC Class Codes: H04J 14/0227 Operation, administration, maintenance or provisioning [OAMP] of WDM networks, e.g. media access, routing or wavelength allocation
• CPC Class Codes: H04J 14/0246 using one wavelength per ONU
• CPC Class Codes: H04J 14/0247 Sharing one wavelength for at least a group of ONUs
• CPC Class Codes: H04J 14/0252 Sharing one wavelength for at least a group of ONUs, e.g. for transmissions from-ONU-to-OLT or from-ONU-to-ONU
• CPC Class Codes: H04J 14/0282 WDM tree architectures
• CPC Class Codes: H04J 14/0298 with sub-carrier multiplexing [SCM]
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
• CPC Class Codes: H04Q 11/0067 Provisions for optical access or distribution networks, e.g. Gigabit Ethernet Passive Optical Network (GE-PON), ATM-based Passive Optical Network (A-PON), PON-Ring
• CPC Class Codes: H04Q 2011/0069 using dedicated optical channels

Abstract

A storage area network extension, network and method include a storage terminal coupled to a remote node. The remote node is connected to a passive optical network (PON) for transferring data signals in the PON and storage signals to/from the storage terminal by employing subcarrier channels in the PON to enable concurrent bidirectional transfer of the data and the storage signals. A storage area network is coupled to the storage terminal and configured to store and retrieve the storage signals for transfer over the PON.

Claims

1. A storage area network extension, comprising:

a storage terminal coupled to a remote node, the remote node being connected to a passive optical network (PON) for transferring data signals in the PON and storage signals to/from the storage terminal by employing subcarrier channels in the PON to enable concurrent bidirectional transfer of the data and the storage signals, wherein the data signals are multiplexed on a baseband signal using time division multiplexing and wherein the storage signals are carried by dedicated passband signals to provide storage data security; and

a storage area network coupled to the storage terminal and configured to store and retrieve the storage signals for transfer over the PON,

wherein the PON includes an optical line terminal (OLT) configured to employ subcarrier modulation (SCM) and parallel signal detection (PSD) to enable the concurrent transmission of the data and the storage signals.

2. The extension as recited in claim 1, wherein the OLT includes a single photo detector to employ parallel signal detection (PSD) for all subcarriers and at least one filter coupled to the photodetector to distinguish received signals.

3. The network as recited in claim 1, further comprising at least one optical network unit (ONU) coupled to a local network to receive and transmit the data signals to and from the OLT.

4. The network as recited in claim 3, wherein the data signals are modulated using time division multiplexing (TDM) and time division multiple access (TDMA) between the ONU and the OLT.

5. The network as recited in claim 1, further comprising a plurality of optical network units (ONU), each ONU employing a different subcarrier wavelength for transferring data signals.

6. An optical network, comprising:

a passive optical network (PON) configured to connect a core network with one of or more local networks for the transfer of data signals multiplexed on a baseband signal using time division multiplexing; and

a storage area network configured to share PON components for transferring storage signals carried by dedicated passband signals to provide storage data security by employing subcarrier channels in the PON to enable concurrent bidirectional transfer of the data and the storage signals,

wherein the PON includes an optical line terminal (OLT) configured to employ subcarrier modulation (SCM) and parallel signal detection (PSD) to enable the concurrent transmission of the data and the storage signals.

7. The network as recited in claim 6, wherein the OLT includes a single photo detector to employ parallel signal detection (PSD) for all subcarriers and at least one filter is employed to distinguish signals.

8. The network as recited in claim 6, further comprising at least one optical network unit (ONU) coupled to a local network to receive and transmit the data signals.

9. The network as recited in claim 6, wherein the data signals are modulated using time division multiplexing (TDM) and time division multiple access (TDMA) between the ONU and the OLT.

10. The network as recited in claim 6, further comprising a plurality of optical network units (ONU), each ONU employing a different subcarrier wavelength for transferring data signals.

11. A method for communication over a passive optical network (PON), comprising:

transferring data signals multiplexed on a baseband signal using time division multiplexing over a passive optical network (PON) which connects a core network with one or more local networks; and

transferring storage signals carried by dedicated passband signals to provide storage data security to and from a storage area network configured to share PON components by employing subcarrier channels in the PON such that concurrent bidirectional transfer of the data and the storage signals is enabled,

wherein the PON includes an optical line terminal (OLT) configured to employ subcarrier modulation (SCM) and parallel signal detection (PSD) to enable the concurrent transmission of the data and the storage signals.

12. The method as recited in claim 11, further comprising modulating/demodulating data signals using time division multiplexing (TDM) and time division multiple access (TDMA) respectively.

13. The method as recited in claim 11, further comprising a plurality of optical network units (ONU), each ONU employing a different subcarrier wavelength for transferring data signals.