Method of establishing a flow in an ATM based MPOA network

In an Asynchronous Transfer Mode (ATM) based Multiple Protocol Over ATM (MPOA) network running LAN Emulation (LE) and having an ingress MPOA Client (I-MPC), ingress MPOA Server (I-MPS), egress MPS (E-MPS) and an egress MPC (E-MPC), a method of controlling the routing of a data flow from a source to a destination, said method comprising the steps of:

• establishing a data path from said source to said destination via a default path established between said I-MPC, said I-MPS, said E-MPS and said E-MPC;
• establishing a data path from said source to said destination via a shortcut path established directly between said I-MPC and said E-MPC;
• providing a security field for indicating whether said flow is permitted to be routed via said shortcut path rather than said default path;
• and
• routing said flow over said default path or said shortcut path in accordance with the contents of said security field.

In an Asynchronous Transfer Mode (ATM) based Multiple Protocol Over ATM (MPOA) network running LAN Emulation (LE) and having an ingress MPOA Client (I-MPC), ingress MPOA Server (I-MPS), egress MPS (E-MPS) and an egress MPC (E-MPC), a method of load sharing a plurality of data flows, said method comprising the steps of:

• establishing a data path from a source to a destination via a default path established between said I-MPC, said I-MPS, said E-MPS and said E-MPC;
• establishing a data path from said source to said destination via a shortcut path established directly between said I-MPC and said E-MPC;
• providing a flow route field for indicating whether said flow is to be routed over said default path or said shortcut path;
• providing a flow priority field for indicating the level of priority assigned to said flow;
• determining whether said flow is to be routed via said default path or said shortcut path in accordance with the level of congestion on said default path and said shortcut path and with the value of said flow priority field associated with said flow;
• and
• routing said flow over said default path or said shortcut path in accordance with the results of said step of determining.

In an Asynchronous Transfer Mode (ATM) based Multiple Protocol Over ATM (MPOA) network running LAN Emulation (LE) and having an ingress MPOA Client (I-MPC), ingress MPOA Server (I-MPS), egress MPS (E-MPS) and an egress MPC (E-MPC), a method of learning about past MPOA resolution successes and failures, said method comprising the steps of:

• establishing a data path from said source to said destination via a default path established between said I-MPC, said I-MPS, said E-MPS and said E-MPC;
• establishing a data path from said source to said destination via a shortcut path established directly between said I-MPC and said E-MPC;
• providing a flow route field for indicating whether said flow is to be routed over said default path or said shortcut path;
• providing a success field for indicating whether the establishment of an MPOA shortcut route was successful or not for this particular flow;
• determining whether the current flow is to be routed over said shortcut route or said default route in accordance with the shortcut establishment successes and failures of one or more previous flows;
• and
• routing said flow over said default path or said shortcut path in accordance with the results of said step of determining.

In an ingress Multiple Protocol Over ATM (MPOA) Client (I-MPC) device, a method of controlling the routing of a data flow from a source to a destination, said method comprising the steps of:

• implementing the client side of the MPOA protocol;
• providing an ingress cache table comprising a flow route field for indicating whether a flow is to be routed over a default path or a shortcut path;
• and
• determining whether a flow is to be routed via said default path or said shortcut path and for setting said flow route field in accordance thereto;
• and
• routing said flow in accordance with said flow route field.

In an ingress Multiple Protocol Over ATM (MPOA) Client (I-MPC) device, a method of load sharing a plurality of data flows, said method comprising the steps of:

• implementing the client side of the MPOA protocol;
• providing an ingress cache table comprising a flow route field for indicating whether a flow is to be routed over a default path or a shortcut path;
• determining the congestion level of said default path and said shortcut path;
• determining, whether a flow is to be routed via said default path or said shortcut path based on said congestion level and for setting said flow route field in accordance thereto;
• and
• routing said flow in accordance with said flow route field.

In an ingress Multiple Protocol Over ATM (MPOA) Client (I-MPC) device, a method of load sharing a plurality of data flows, said method comprising the steps of:

• implementing the client side of the MPOA protocol;
• providing an ingress cache table comprising a flow route field for indicating whether a flow is to be routed over a default path or a shortcut path and a flow priority field for indicating the priority assigned to a flow;
• determining the congestion level of said default path and said shortcut path;
• determining, whether a flow is to be routed via said default path or said shortcut path based on said congestion level and for setting said flow route field in accordance thereto;
• and
• routing said flow in accordance with said flow route field.

In an ingress Multiple Protocol Over ATM (MPOA) Client (I-MPC) device, a method comprising the steps of:

• implementing the client side of the MPOA protocol;
• providing an ingress cache table comprising a flow route field for indicating whether a flow is to be routed over a default path or a shortcut path and an establishment success field for indicating the success or failure of the establishement attempt of a shortcut path;
• storing the results of attempts to establish shortcut virtual circuits in said establishment success field of said ingress cache table;
• searching said ingress cache table for similar flows upon said MPC means receiving a new flow;
• determining, whether a flow is to be routed via said default path or said shortcut path based on said step of searching and for setting said flow route field in accordance thereto;
• and
• routing said flow in accordance with said flow route field.