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US 5,856,972 AGranted
Duplicate message detection method and apparatus
AssigneeEchelon Corporation
InventorsGlen M. Riley, Robert A. Dolin, Jr.
Life of this patent
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AssigneeEchelon Corporation
InventorsGlen M. Riley, Robert A. Dolin, Jr.
Estimating the term…
A method of determining a transaction identifier for a message to be sent from a node on a network. The node has an address table and a memory. The method comprising the steps of: accessing the address table to determine an address for the message; and accessing the transaction identifier at a memory location corresponding to the address.
An apparatus for communicating messages on a network, said apparatus including:
A method for determining a transaction identifier for a message to be sent from a node on a network, said node having an address table and a memory, said method comprising the steps of:
A node for preparing a message for transmission to one of a plurality of other nodes on a network, said node comprising:
A method of generating a transaction identifier for a message, said message to be sent on a network from a node, said message including information for a second node in said network, said node including a processor and a memory, said processor being coupled to said memory, said node being coupled in communications with said network, said method comprising the steps of:
An apparatus for communicating messages on a network, said apparatus including:
A method of generating a transaction identifier for a message to be sent from a first node to a second node on a network including a plurality of nodes, said first node including a processor and a memory coupled to said processor, said method comprising the steps of:
Dependencies are inferred from the claim text.
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From the US filing history. Foreign family members aren’t listed.
Arrangements specially adapted for the transmitter end: scheduling and prioritising arrangements
Arrangements specially adapted for the receiver end: scheduling and prioritising arrangements
Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols: network security protocols
By using return channel: in which the return channel carries supervisory signals, e.g. repetition request signals
Term ended 1 Sep 2014 (estimated)
USPTO file history isn’t available for this patent, so only indexed dates are shown.
1. Field of Invention
The present invention relates to the field of network communications. In particular, the present invention describes improved duplicate message detection.
2. Description of Related Art
The present invention is illustrated by way of example, and not limitation, in the figures. Like references indicate similar elements.
FIG. 1 illustrates a node upon which one embodiment of the present invention can be implemented.
FIG. 2 illustrates an example control system network.
An improved method and apparatus for detecting duplicate messages is described. In the following description, numerous specific details are set forth such as a variable configuration table entry format, etc., in order to provide a thorough understanding of the present invention. It will be obvious, however, to one skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known circuits, structures and techniques have not been shown in detail in order not to unnecessarily obscure the present invention.
Some embodiments of the present invention use different data structures than those described in detail herein. For example, sets, collections, lists, or arrays, can be used instead of tables. Therefore, when a reference is made to a particular data structure, a different data structure can be substituted without deviating from the scope of the invention. Often, what is important is the kinds of data contained in the data structures, not necessarily the actual data structures themselves.
In one embodiment of the present invention, a separate transaction id space is maintained for each address that a sender node can communicate to (the sender node's list of addresses). This effectively increases the usable transaction space for each network address, without increasing the number of bits needed to represent a transaction id. In one embodiment, duplicate addresses can occur in the sender node's list of addresses. In this embodiment, the sender node uses the same transaction space for the two (or more) addresses. This helps prevent a receiver from erroneously identifying a message as being a duplicate message.