What happens if the device does not know the MAC address of the router it wants to use to perform indirect routing services?
the source issues an ARP request.
The ARP request will be picked up by a router connected to the same network as the source.
This router will issue an ARP reply to the device that originated the ARP request.
The reply will contain the MAC address of the non-local router.
Thus, without the ARP request ever going beyond the local network, the source is able to obtain the addressing information it needs in order to send data to devices located on distant networks.