To forward packets by the best possible route, NetWare routers maintain a routing information table that holds information about all the segments on the network. Ticks to LAN segment Contains an estimate of the time necessary to reach the destination segment.
Immediate address Contains the node number of the router that can forward packets to each segment.
The method that drivers use for estimating the time delay on a segment depends on the segment type. For example, the delay for a T1 link normally ranges from six to seven ticks. If this delay changes, the driver will inform its router. For NetWare versions prior to 2.16c, the routing information table keeps a list of all alternate routes for each network number in case the primary shortest route to a network number goes down. In other words, if the router can reach the segment through more than one of its NICs, it will make a record of all routes.