Library /sys$common/syshlp/nclhelp.hlb set, routing, phaseiv_maximum_visits  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Support: All
    Default: 63            Value: 1-63

    Maximum number of visits that a packet can make to this node
    before Routing assumes that the packet is looping. This
    characteristic is only used by the Phase IV routing algorithm
    (that is, the routing-vector algorithm).