Network efficiency is improved by building and maintaining path integrity
tables in nodes of a network. The tables include path integrity
information for paths associated with the nodes. A path is defined by a
source address, a destination address and a port or version number. Once
a node is made aware of a path, either by handling network message
traffic associated with the path or through manual entry, the node
maintains path status information with information provided by normal
network message traffic, or absent the normal network message traffic, by
transmitting Echo Request messages and processing information related to
Echo Response messages or the lack thereof. Information related to paths
that are disabled for longer than a disabled path duration limit is
deleted from the tables. A Gratuitous GTP Echo Response message can
notify other nodes of an administrative state change in a node.