Communication system and method for an optical local area network

Abstract

An optical local area network includes a passive optical distribution fabric interconnecting a plurality of nodes including a first node and a plurality of remaining nodes, a hub that includes the first node and a control module, and a client network adapter coupled to each of the remaining nodes for responding to the control module. The control module controls timing for each of the client network adapters to transmit signals over the passive optical distribution fabric and distribution of signals to each of the nodes.

What is claimed is: 
     
         1 . A Local Area Network (LAN) client for a passive optical LAN, the passive optical LAN disposed to having one or more passive optical splitters for coupling the LAN client over one or more optical fibers to the head end of the passive optical LAN, the LAN client for a passive optical LAN comprising of:
 an optical interface for converting a downstream optical signal on a downstream optical wavelength to a downstream electrical signal and for converting an upstream electrical signal to an upstream optical signal and emitting the upstream optical signal on an upstream optical wavelength;   at least one network interface for receiving user data; and   a control module electrically coupled to the optical interface and electrically coupled to the at least one network interface and wherein the control module processes the downstream electrical signal having a downstream control and downstream data information to recover an upstream bandwidth allocation from the downstream control information and wherein the control module receives user data from the at least one network interface and the control module responsive to the upstream bandwidth allocation generates the upstream electrical signal having upstream control and upstream data information and wherein at least a portion of the user data is included in the upstream data information,   whereby the LAN client for a passive optical LAN communicates user data upstream responsive to an upstream bandwidth allocation.   
     
     
         2 . The LAN client for a passive optical LAN of  claim 1 , wherein the control module includes an Ethernet MAC. 
     
     
         3 . The LAN client for a passive optical LAN of  claim 1 , wherein the control module includes a passive optical LAN protocol processor. 
     
     
         4 . The LAN client for a passive optical LAN of  claim 1 , wherein the control module further adjusts timing of the generation of the upstream electrical signal responsive to receiving a response delay message. 
     
     
         5 . The LAN client for a passive optical LAN of  claim 1 , wherein the control module is configured to receive in the downstream electrical signal a network identification address assigned to the LAN client and wherein the network identification address can be used by the control module for receiving downstream data information addressed to the LAN client for a passive optical LAN. 
     
     
         6 . The LAN client for a passive optical LAN of  claim 1 , wherein the control module performs operation administration and maintenance (OAM) message processing. 
     
     
         7 . The LAN client for a passive optical LAN of  claim 1 , wherein the control module is configured to manage the transmission and reception of optical data link layer communications through the optical interface based on at least one optical data link layer address and wherein the control module includes an Ethernet Media Access Control (MAC) configured to enable Ethernet communications through the at least one network interface. 
     
     
         8 . The LAN client for a passive optical LAN of  claim 1 , wherein the LAN client adjusts the optical power level of the upstream optical signal responsive to receiving a message. 
     
     
         9 . The LAN client for a passive optical LAN of  claim 1 , wherein the LAN client receives a request for new LAN clients to identify themselves and the LAN client responds with a message including a serial number for identifying the LAN client. 
     
     
         10 . The LAN client for a passive optical LAN of  claim 1 , wherein the downstream control information includes a consecutive sequence of bits for the LAN client to identify the beginning of a downstream frame, wherein the downstream frame includes the downstream control and data information. 
     
     
         11 . The LAN client for a passive optical LAN of  claim 1 , wherein the upstream control information includes user data buffering status information. 
     
     
         12 . The LAN client for a passive optical LAN of  claim 1 , wherein the control module processes the downstream electrical signal having successive downstream frames. 
     
     
         13 . The LAN client for a passive optical LAN of  claim 12 , wherein a downstream frame includes a first number of downstream subframes having one or more downstream formats and wherein each downstream subframe includes a second number of downstream slots of time. 
     
     
         14 . The LAN client for a passive optical LAN of  claim 13 , wherein a downstream subframe includes a downstream communication channel for communicating the upstream bandwidth allocation for provisioning upstream slots of time to the LAN client for a passive optical LAN. 
     
     
         15 . The LAN client for a passive optical LAN of  claim 12 , wherein a downstream frame includes downstream packet data and wherein downstream packet data includes a downstream packet header and downstream packet payload and wherein the downstream packet header includes a field indicating the length of the downstream packet payload. 
     
     
         16 . The LAN client for a passive optical LAN of  claim 15 , wherein the downstream packet payload includes at least a portion of an Ethernet frame or a Fibre Channel frame. 
     
     
         17 . The LAN client for a passive optical LAN of  claim 1 , wherein the upstream optical signal is emitted in one or more upstream slots of time forming one or more upstream frames as governed by the upstream bandwidth allocation. 
     
     
         18 . The LAN client for a passive optical LAN of  claim 17 , wherein upstream frames includes a first number of upstream subframes having one or more upstream formats. 
     
     
         19 . The LAN client for a passive optical LAN of  claim 17 , wherein upstream frames includes an upstream packet header and an upstream packet payload and wherein the upstream packet header includes a field indicating an upstream packet payload length. 
     
     
         20 . The LAN client for a passive optical LAN of  claim 19 , wherein the upstream packet payload includes at least a portion of an Ethernet frame or a Fibre Channel frame. 
     
     
         21 . The LAN client for a passive optical LAN of  claim 1 , wherein the optical interface includes one or more optical fiber connectors selected from the group consisting essentially of:
 Subscriber Connector (SC);   Lucent Connector (LC);   Fiber Channel (FC);   Straight TP (ST); and   Miniature Unit (MU).   
     
     
         22 . The LAN client for a passive optical LAN of  claim 1 , wherein the at least one network interface is configured to communicate using a protocol from the group consisting essentially of:
 IEEE 10 Mbit Ethernet;   IEEE 100 Mbit Ethernet;   IEEE 1000 Mbit Ethernet;   Fibre Channel;   IEEE 802.11;   IEEE 802.16; and   Digital Subscriber Line (DSL)   
     
     
         23 . A Local Area Network (LAN) client for a passive optical LAN, the passive optical LAN disposed to having one or more passive optical splitters for coupling the LAN client over one or more optical fibers to the head end of the passive optical LAN, the LAN client for a passive optical LAN comprising of:
 an optical interface for converting a downstream optical signal on a downstream optical wavelength to a downstream electrical signal and for converting an upstream electrical signal to an upstream optical signal and emitting the upstream optical signal on an upstream optical wavelength;   at least one network interface for receiving user data; and   a control module electrically coupled to the optical interface and electrically coupled to the at least one network interface and wherein the control module processes the downstream electrical signal having a downstream control and downstream data information to recover an upstream bandwidth allocation from the downstream control information wherein the upstream bandwidth allocation includes a start and end time slot number or a start time and length of time and wherein the control module receives user data from the at least one network interface and the control module responsive to the upstream bandwidth allocation generates the upstream electrical signal having upstream control and upstream data information and wherein at least a portion of the user data is included in the upstream data information,   whereby the LAN client for a passive optical LAN communicates user data upstream responsive to an upstream bandwidth allocation.   
     
     
         24 . A Local Area Network (LAN) client for a passive optical LAN, the passive optical LAN disposed to having one or more passive optical splitters for coupling the LAN client over one or more optical fibers to the head end of the passive optical LAN, the LAN client for a passive optical LAN comprising of:
 an optical interface for converting a downstream optical signal on a downstream optical wavelength to a downstream electrical signal and for converting an upstream electrical signal to an upstream optical signal and emitting the upstream optical signal on an upstream optical wavelength;   at least one network interface for receiving user data; and   a control module electrically coupled to the optical interface and electrically coupled to the at least one network interface and wherein the control module processes the downstream electrical signal having a downstream control and downstream data information to recover an upstream bandwidth allocation from the downstream control information wherein the upstream bandwidth allocation includes a start and end time slot number or a start time and length of time and wherein the control module receives user data from the at least one network interface and the control module responsive to the upstream bandwidth allocation generates the upstream electrical signal having upstream control and upstream data information and wherein at least a portion of the user data is included in the upstream data information,   whereby the LAN client for a passive optical LAN ends the optical upstream signal emissions responsive to the end time slot number or the end of the length of time and whereby the LAN client for a passive optical LAN communicates user data upstream responsive to an upstream bandwidth allocation.