Addr Encap Interface 53.24 - Hardware 0000. Routers must have a unique address for each AppleTalk interface as well. Certain router implementations do not support dynamic assignment, so addresses must be explicitly assigned to each AppleTalk interface through the router s configuration management system. Other routers perform AARP as described. An end node obtains zone and internetwork information from routers on the network by broadcasting ZIP messages requesting this information.
Routers supply the zone name to network range bindings in ZIP replies.
Like IP and IPX, routers forward data packets from source nodes to destination nodes across heterogeneous media. When a router receives a DDP packet, it checks to see if the packet's destination network number is the local network. If it is, the router passes the packet down to the data link layer which forwards the packet toward the destination node. If the destination network number is a different network, the router refers to its routing tables to determine the next hop on the shortest path toward the destination. When the router attempts to send a packet to a given AppleTalk address, it scans its local AARP cache to find the corresponding hardware address.