US 6,985,488 B2 · Method and apparatus for transporting packet data over an optical network

Abstract

A method, apparatus and network for transporting layer-2 frames, such as Ethernet MAC, ATM AAL5, and Frame Relay, over SONET, SDH, or OTN transport networks is disclosed. The method establishes “pseudo-wires” between, for example, SONET switches and directly on top of the SONET layer. The method may implement MPLS signaling protocols on traditional SONET switches for the purpose of aggregating layer-2 frames from the transport network edges, while the transport network itself is independent from IP and MPLS routing. This approach provides a number of advantages to the network carriers in terms of operation and equipment expense reduction. To enable the transport network to be independent from IP and MPLS, and avoid subsequent IP control message processing inside the networks, an edge-to-edge “tunneling” mechanism is designed to transmit control messages as a part of the SONET (or SDH or OTN) frame payload.

Claims25

Dependent claims

A method of transporting packet data and command messages through a communications network having at least one optical connection provided between provider edge nodes of the communications network, comprising:

establishing a pseudo-wire directly over the optical connection and between the provider edge nodes of the communications network;
tunneling the packet data within the established pseudo-wire and over the optical connection established between the provider edge nodes of the communications network;
tunneling command messages within the same optical connection established that is used to transport the packet data between the provider edge nodes of the communications network;
said establishing a pseudo-wire including negotiating an encapsulation label for the packet data to be transmitted between the provider edge nodes;
said tunneling packet data including utilizing the negotiated encapsulation label for the packet data;
and
associating the tunneled packet data with a corresponding tunneled command message,
said associating step including building a session table storing the negotiated encapsulation label for the packet data associated with the command message, the command message encapsulation label, and a control message ID.

5 more elements

A method of transporting a customer data flow including a sequence of data packets that are associated with one another over an optical network, comprising:

terminating client frames in the customer data flow holding the sequence of data packets;
appending an encapsulation label to the data packets whose client frames have been terminated;
originating an optical connection between provider edge nodes of the optical network to carry the data packets with the appended encapsulation label;
transmitting the data packets with the appended encapsulation label over the optical connection using an optical signal transport frame;
tunneling at least one command message associated with the customer data flow within the optical signal transport frame used by said transmitting step;
aggregating a plurality of data flows each of which includes a sequence of data packets that are associated therewith;
said terminating step terminating client frames in each of the customer data flows;
said appending step appending a different encapsulation label to the data packets from different customer flows;
said originating an optical connection step originating an optical connection between provider edge nodes of the optical network to carry one or more of the sequences of data packets associated with the plurality of data flows;
said transmitting step transmitting the sequences of data packets with the appended encapsulation labels over the optical connection using optical signal transport framing;
and
tunneling at least one command message associated with at least one of the customer data flows within the optical signal transport frame used by said transmitting step.

9 more elements

A packet processing engine for a provider edge node of an optical communications network, comprising:

a session table storing outgoing optical circuit connection identification data and encapsulation label data associated with control messages;
and
a controller operatively connected to said session table, said controller looking up the data stored in said session table to determine the encapsulation label and outgoing optical circuit connection for a received control message;
said controller encapsulating the received control message with the determined encapsulation label and injecting the encapsulated control message into the determined outgoing optical circuit connection.

1 more element

Dependencies are inferred from the claim text.

Method and apparatus for transporting packet data over an optical network

Life of this patent

Method and apparatus for transporting packet data over an optical network

Life of this patent

Abstract

Claims25