NAME

       imcrc - IMC scheme configuration commands file

DESCRIPTION

       IMC scheme configuration commands are passed to ipnadmin either in a file of text lines or
       interactively at ipnadmin's command prompt (:).  Commands are interpreted line-by line,
       with exactly one command per line.

       IMC scheme configuration commands simply establish which nodes are the local node's
       parents and children within a single IMC multicast tree.  This single spanning tree, an
       overlay on a single BP-based network, is used to convey all multicast group membership
       assertions and cancellations in the network, for all groups.  Each node privately tracks
       which of its immediate "relatives" in the tree are members of which multicast groups and
       on this basis selectively forwards -- directly, to all (and only) interested relatives --
       the bundles destined for the members of each group.

       Note that all of a node's immediate relatives in the multicast tree must be among its
       immediate neighbors in the underlying network.  This is because multicast bundles can only
       be correctly forwarded within the tree if each forwarding node knows the identity of the
       relative that passed the bundle to it, so that the bundle is not passed back to that
       relative creating a routing loop.  The identity of that prior forwarding node can only be
       known if the forwarding node was a neighbor, because no prior forwarding node (aside from
       the source) other than the immediate proximate (neighboring) sender of a received bundle
       is ever known.

       IMC group IDs are unsigned integers, just as IPN node IDs are unsigned integers.  The
       members of a group are nodes identified by node number, and the multicast tree parent and
       children of a node are neighboring nodes identified by node number.

       The formats and effects of the IMC scheme configuration commands are described below.

GENERAL COMMANDS

       ?   The help command.  This will display a listing of the commands and their formats.  It
           is the same as the h command.

       #   Comment line.  Lines beginning with # are not interpreted.

       e { 1 | 0 }
           Echo control.  Setting echo to 1 causes all output printed by ipnadmin to be logged as
           well as sent to stdout.  Setting echo to 0 disables this behavior.

       h   The help command.  This will display a listing of the commands and their formats.  It
           is the same as the ? command.

KINSHIP COMMANDS

       a node_nbr { 1 | 0 }
           The add kin command.  This command adds the neighboring node identified by node_nbr as
           an immediate relative of the local node.  The Boolean value that follows the node
           number indicates whether or not this node is the local node's parent within the tree.

       c node_nbr { 1 | 0 }
           The change kin command.  This command changes the parentage status of the indicated
           relative according to Boolean value that follows the node number, as noted for the add
           kin command.

       d node_nbr
           The delete kin command.  This command deletes the immediate multicast tree relative
           identified by node_nbr.  That node still exists but it is no longer a parent or child
           of the local node.

       i node_nbr
           This command will print information (the parentage switch) for the multicast tree
           relative identified by node_nbr.

       l   This command lists all of the local node's multicast tree relatives, indicating which
           one is its parent in the tree.

EXAMPLES

       a 983 1
           Declares that 983 is the local node's parent in the network's multicast tree.

SEE ALSO

       imcadmin(1)