bpclock - Online in the Cloud

PROGRAM:

NAME

bpclock - Bundle Protocol (BP) daemon task for managing scheduled events

SYNOPSIS

bpclock

DESCRIPTION

bpclock is a background "daemon" task that periodically performs scheduled Bundle Protocol
activities. It is spawned automatically by bpadmin in response to the 's' 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.

Once per second, bpclock takes the following action:

First it (a) destroys all bundles whose TTLs have expired, (b) enqueues for re-
forwarding all bundles that were expected to have been transmitted (by convergence-
layer output tasks) by now but are still stuck in their assigned transmission queues,
and (c) enqueues for re-forwarding all bundles for which custody has not yet been
taken that were expected to have been received and acknowledged by now (as noted by
invocation of the bpMemo() function by some convergence-layer adapter that had CL-
specific insight into the appropriate interval to wait for custody acceptance).

Then bpclock adjusts the transmission and reception "throttles" that control rates of
LTP transmission to and reception from neighboring nodes, in response to data rate
changes as noted in the RFX database by rfxclock.

bpclock then checks for bundle origination activity that has been blocked due to
insufficient allocated space for BP traffic in the ION data store: if space for bundle
origination is now available, bpclock gives the bundle production throttle semaphore
to unblock that activity.

Finally, bpclock applies rate control to all convergence-layer protocol inducts and
outducts:

For each induct, bpclock increases the current capacity of the duct by the
applicable nominal data reception rate. If the revised current capacity is
greater than zero, bpclock gives the throttle's semaphore to unblock data
acquisition (which correspondingly reduces the current capacity of the duct) by
the associated convergence layer input task.

For each outduct, bpclock increases the current capacity of the duct by the
applicable nominal data transmission rate. If the revised current capacity is
greater than zero, bpclock gives the throttle's semaphore to unblock data
transmission (which correspondingly reduces the current capacity of the duct) by
the associated convergence layer output task.

EXIT STATUS

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

"1" bpclock was unable to attach to Bundle Protocol operations, probably because bpadmin
has not yet been run.

Use bpclock online using onworks.net services