nd forwards the packet to one of its network interfaces. The forwarding decision is usually done by looking up the destination address from another data structure called a forwarding table. The forwarding table is created by the router using the routing table and possible routing policies existing in the router. The router then creates a table where it lists which networks are accessible through which of the router's network interfaces. An IP router looks at every IP packet individually and does the forwarding decision on a packet-by-packet basis. If something changes in the router's routing table, a packet can take a different route from a preceding packet even if it has the same destination. In addition to routers, hosts make forwarding decisions. For instance, a host has to decide if it thinks the destination host is directly connected to it, or if it has to forward the packet to a router instead. This first router is often called the first-hop router. There may be multiple routers available in a network of which the host can choose. One of these routers is usually assigned as the default router for the host. If the host has no more specific information about the location of the destination host, the host sends the packet to the default router. Hence, the host's default route points to that default router. In the same way as routers may be configured with routing policy, the host might have a set routing or forwarding policy. The reasons for the policies include, security, some assumption about the cost or characteristics of a network connection, or just user Introduction preference. A corporate IT-department might configure the user's traffic to always go through an active VPN tunnel regardless of where the packet is going, in order to make sure that company secrets do not traverse through unknown networks. Some operating systems prefer a wireline connection over wireless because it is assumed to have more bandwidth and be more reliable, and some operating systems allow the user to define the preference order