Router VE1 has just received a packet and needs to route it. What two actions must this router take in order to route incoming p

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问题 Router VE1 has just received a packet and needs to route it. What two actions must this router take in order to route incoming packets? (Choose two)
A. Inspect the routing table to select the best path to the destination network addresses.
B. Validate sources of routing information.
C. Inspect the ARP table to verify a legitimate source MAC address for each packet.
D. Identify the destination network address of each packet.
E. Verify the receipt of routed packets by the next hop router.
F. Identify the source network address of each packet.

选项

答案A,D

解析 Explanation:
The router decides how to forward an incoming packet by finding the routes that "match" the destination address of the packet, and then forwarding it according to the most narrowly applicable one.

A packet matches a route in the following way: a packet has (among other things) a destination address in its header, a route contains either a network or a host address, a network mask (netmask), and instructions on how to forward a packet using the route.

The packet matches the route if its destination address is part of the address subspace defined by the network address or exactly matches the host address of the route. A route is more narrowly applicable than another if the address subspace defined by its network address contains fewer actual addresses than the other, which is indicated by the netmask. An entry with a host address, rather than a network address, is the narrowest kind.
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