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Caveat on using Cached Routes

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• A caveat in short-circuiting the Route Request operation
  • Consider the following wireless network topology:

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  • Suppose that node K has just found a source route to node D:

    Node K sent a ROUTE REQUEST for node D: And node K got back a ROUTE REPLY from node D: Node K now has a source route to node D (and can short-circuit route request for destination D)

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  • Now consider the following Route Request operation:

    Node A sends a ROUTE REQUEST for node D: When the ROUTE REQUEST arrives at node K: Node K could short-circuit the ROUTE REQUEST: However, that would result in the following inferior source route:

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  • Rule to prevent the creation of inferior routes:Sour

    If the current source path in the route record contains a node in the appended source path: then: Short-cirucuiting the ROUTE REQUEST message is not allowed !!!