4.1. Task 4.1: Using ARP Utilities

IP devices keep a table known as an ARP cache. A cache is a temporary table, the contents of which age and disappear from the table from lack of use, based on a configurable timer. Each time the entry is used, its individual timer is reset, lengthening its stay in the cache. An ARP cache stores IP-address-to-MAC-address resolutions for other IP devices on the local subnet. Recall that IP hosts build their ARP cache through link-local broadcasts that remain on the immediate subnet only. An ARP broadcast goes out when the routing process, on either a source or intermediate system, determines the next-hop device, even if it's the final destination, which lies in its local subnet by definition.

The Layer 2 frame's ...

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