×

System for locating a node containing a requested resource and for selectively verifying the presence of the resource at the node

  • US 5,222,242 A
  • Filed: 09/28/1990
  • Issued: 06/22/1993
  • Est. Priority Date: 09/28/1990
  • Status: Expired due to Fees
First Claim
Patent Images

1. In a computer network which includes a plurality of end nodes, at least one network node server for each of said end nodes, and resources associated with said end nodes and said network nodes, each said network node server having a cache directory of information relating to the location and characteristics of at least some of the resources in the network, a method of initiating establishment of a session between a source logical unit associated with a network resource at one of said end nodes and network nodes and a target logical unit associated with a network resource at another one of said end nodes and network nodes, said method comprising the steps of:

  • generating a LOCATE request at the source logical unit, said LOCATE request identifying a target resource at the target logical unit and including a verification flag indicating whether the location and characteristics of the target resource need be verified in a reply to the LOCATE request;

    transmitting the LOCATE request to the network node server for the node containing the source logical unit; and

    processing the LOCATE request at the network node server, said processing step further comprising the steps ofsearching the cache directory of the network node for any entry relating to the target resource,if target resource the entry is not found in the searched directory, then initiating a search for the target resource elsewhere in the network by forwarding the search request to other nodes in the network,if the target resource entry is found in the searched directory, then checking the verification flag in the LOCATE request to determine whether the resource location and characteristics are to be verified,if the verification flag indicates verification is not required, returning a LOCATE reply to the node containing the source logical unit, said LOCATE reply being based on the contents of the directory entry,if the verification flag indicates verification is required, forwarding the LOCATE request to the node identified in the directory entry as containing the target resource, receiving a LOCATE reply originating at the node identified in the directory entry, and returning the LOCATE reply to the node containing the source logical unit, said LOCATE reply being based on the verified contents of the directory entry.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×