Which two benefits are provided by using a hierarchical addressing network addressing scheme?

Which two benefits are provided by using a hierarchical addressing network addressing
scheme? (Choose two.)

A.
reduces routing table entries

B.
auto-negotiation of media rates

C.
efficient utilization of MAC addresses

D.
dedicated communications between devices

E.
ease of management and troubleshooting

Explanation:
Here are some of the benefits of hierarchical addressing:
Reduced number of routing table entries—Whether it is with your Internet routers or your
internal routers, you should try to keep your routing tables as small as possible by using
route summarization. Route summarization is a way of having a single IP address represent
a collection of IP addresses; this is most easily accomplished when you employ a
hierarchical addressing plan. By summarizing routes, you can keep your routing table entries
(on the routers that receive the summarized routes) manageable, which offers the following
benefits:
More efficient routing
A reduced number of CPU cycles when recalculating a routing table or sorting through the
routing table entries to find a match
Reduced router memory requirements
Reduced bandwidth required to send the fewer, smaller routing updates
Faster convergence after a change in the network
Easier troubleshooting
Increased network stability

Efficient allocation of addresses—Hierarchical addressing lets you take advantage of all
possible addresses because you group them contiguously
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