NAME

       imcfw - bundle route computation task for the IMC scheme

SYNOPSIS

       imcfw

DESCRIPTION

       imcfw is a background "daemon" task that pops bundles from the queue of bundle destined
       for IMC-scheme (Interplanetary Multicast) endpoints, determines which "relatives" on the
       IMC multicast tree to forward the bundles to, and appends those bundles to the appropriate
       queues of bundles pending transmission to those proximate destinations.

       For each possible proximate destination (that is, neighboring node) there is a separate
       queue for each possible level of bundle priority: 0, 1, 2.  Each outbound bundle is
       appended to the queue matching the bundle's designated priority.

       Proximate destination computation is determined by multicast group membership as resulting
       from nodes' registration in multicast endpoints, governed by multicast tree structure as
       configured by imcadmin(1).

       imcfw is spawned automatically by bpadmin in response to the 's' (START) command that
       starts operation of Bundle Protocol on the local ION node, and it is terminated by bpadmin
       in response to an 'x' (STOP) command.  imcfw can also be spawned and terminated in
       response to START and STOP commands that pertain specifically to the IMC scheme.

EXIT STATUS

       "0" imcfw terminated, for reasons noted in the ion.log log file.  If this termination was
           not commanded, investigate and solve the problem identified in the log file and use
           bpadmin to restart imcfw.

       "1" imcfw could not commence operations, for reasons noted in the ion.log log file.
           Investigate and solve the problem identified in the log file, then use bpadmin to
           restart imcfw.

FILES

       No configuration files are needed.

ENVIRONMENT

       No environment variables apply.

DIAGNOSTICS

       The following diagnostics may be issued to the ion.log log file:

       imcfw can't attach to BP.
           bpadmin has not yet initialized BP operations.

       imcfw can't load routing database.
           ipnadmin has not yet initialized the IPN scheme.

       Can't create lists for route computation.
           An unrecoverable database error was encountered.  imcfw terminates.

       'imc' scheme is unknown.
           The IMC scheme was not added when bpadmin initialized BP operations.  Use bpadmin to
           add and start the scheme.

       Can't take forwarder semaphore.
           ION system error.  imcfw terminates.

       Can't exclude sender from routes.
           An unrecoverable database error was encountered.  imcfw terminates.

       Can't enqueue bundle.
           An unrecoverable database error was encountered.  imcfw terminates.

BUGS

       Report bugs to <ion-bugs@korgano.eecs.ohiou.edu>

SEE ALSO

       bpadmin(1), imcadmin(1), bprc(5), imcrc(5)