Operations, administration and maintenance (OAM) systems and methods for packet switched data networks
View Patent ↗The invention includes a protocol, systems and methods for operating, administering, and maintaining (OAM) physical links in a network that carries packet switched data. A network control point implementing the protocol assigns addresses to all ports of the network, discovers network topology and capabilities, and initializes remote parameters through OAM frames sent to the ports. The OAM protocol maintains all physical transmission links through the communication of OAM frames with information concerning link errors and the status of ports and boxes. The OAM frame has a preamble that is an inverse of a preamble of a data frame, allowing decoupling of the OAM and data services. The OAM frames are initiated and terminated at the physical layer of the network. Ports of the network may include ASIC integrated circuits that create, transmit, receive, and process the OAM frames at the physical layer of the ports.
1. A data communication method comprising:
forming or receiving first and second data frames, the first and second data frames each having a preamble and a payload following the preamble, the preamble of the first data frame being an inverse of the preamble of the second data frame; and
forwarding the first and second data frames to different protocol stack layer recipients based on the different preambles thereof.
2. The method of claim 1 , wherein a sole recipient of any forwarded said first data frame is a physical layer of a protocol stack, any said second data frame being forwarded to a layer of the protocol stack higher than the physical layer.
3. The method of claim 1 , wherein the different recipients are different layers of a protocol stack.
4. A data communication method comprising:
receiving first and second data frames, the first and second data frames including a preamble and a payload following the preamble; and
multiplexing the first and second data frames between a plurality of possible protocol services based on a contents of the different preambles thereof,
wherein the preamble of the first data frame is an inverse of the preamble of the second data frame.
5. The method of claim 4 , wherein a preamble having a first bit pattern causes the first data frame to be forwarded in the multiplexing step to a physical layer port, and a preamble having a second bit pattern causes the first data frame to be forwarded in the multiplexing step to a protocol layer higher than the physical layer.
6. A data communication method comprising:
receiving first and second frames, each of the first and second frames including a preamble, the second frame including an initial portion serving as a start of frame delimiter;
multiplexing the second frame between a plurality of possible protocol services based on a content of the initial portion,
wherein the preamble of the first frame is an inverse of the preamble of the second frame.