The additional code in the network stack decodes and validates the DTN option included in the packet. If the
packet is a new DTN enabled packet the packet is stored, if possible, in a new record in the DTN custody store and
timers are set for the packet expiry. The packet then continues through the Contiki uIP networking stack as usual and
is forwarded onto the next node or passed to the receive code as required. This allows packets to be passed through
the network without additional delay if the network is up. As this is done regardless of whether the packet could be
stored or not, it also allows packets to bypass nodes that have filled up the custody packet buffer.