Method for requesting identification of a neighbor node in a data processing I/O system
First Claim
1. In a computer system having a plurality of communicating nodes in a network of communicating nodes, in which each of said communicating node has a unique identifier which does not change if a node location is later changed in the network, the method comprising the steps of:
- communicating by any node with not more than one neighboring node at a time in a selected transmission direction without requiring an identifier of the neighboring node for requesting the identifier of the neighboring node;
sending by a requesting node of a request-identifier frame to the one neighboring node in the selected transmission direction within the network of communication nodes;
transmitting by the neighboring node of an identifier-response frame to said requesting node in response to the sending step, said identifier-response frame including a validity code for indicating if the identifier-response frame contains a valid identifier of the neighboring node;
returning by the neighboring node of a not-available-indicator value in a valid field of the identifier-response frame if a previously established identifier for the neighboring node is not available to the neighboring node,returning by the neighboring node of an available-indicator value in the valid field if the identifier of the neighboring node is available to the neighboring node;
repeating the sending step by the requesting node if said not-available-indicator value in the identifier-response frame is received by the requesting node; and
suspending the sending step when the repeating step is unsuccessful.
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Accused Products
Abstract
A method for acquiring the node identifier of a node in a data processing input/output (I/O) system having a plurality of nodes. This procedure is part of the initialization of each node in the I/O system and may be used to establish the configuration of the I/O system such that if a connection breaks or a fault occurs between nodes, the configuration can be confirmed after the break or fault is corrected. This prevents data from being sent to the wrong device if lines were connected in a different configuration during the correction of a fault. The node identifier is a worldwide-unique identifier such that only one node is identified by a node identifier. The node identifier contains a validity code that specifies if the node identifier is valid. Also disclosed is a retry procedure for retrying the acquisition of a node identifier if the acquired node identifier is not valid, and a deferral procedure which defers the retry procedure if a link is not available.
65 Citations
9 Claims
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1. In a computer system having a plurality of communicating nodes in a network of communicating nodes, in which each of said communicating node has a unique identifier which does not change if a node location is later changed in the network, the method comprising the steps of:
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communicating by any node with not more than one neighboring node at a time in a selected transmission direction without requiring an identifier of the neighboring node for requesting the identifier of the neighboring node; sending by a requesting node of a request-identifier frame to the one neighboring node in the selected transmission direction within the network of communication nodes; transmitting by the neighboring node of an identifier-response frame to said requesting node in response to the sending step, said identifier-response frame including a validity code for indicating if the identifier-response frame contains a valid identifier of the neighboring node; returning by the neighboring node of a not-available-indicator value in a valid field of the identifier-response frame if a previously established identifier for the neighboring node is not available to the neighboring node, returning by the neighboring node of an available-indicator value in the valid field if the identifier of the neighboring node is available to the neighboring node; repeating the sending step by the requesting node if said not-available-indicator value in the identifier-response frame is received by the requesting node; and suspending the sending step when the repeating step is unsuccessful. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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Specification