Final answer:
New ARP table entries are created when a client issues an ARP request for an IP address not currently in the table, leading to other devices responding with the required MAC address, which is then added to the ARP table.
Step-by-step explanation:
When a client makes an ARP request that cannot be satisfied by the data already present in the ARP table, it results in the creation of new ARP table entries. The ARP (Address Resolution Protocol) table is used to maintain a correlation between IP addresses and MAC addresses. When a device wants to communicate with another device on the network, it checks its ARP table to find the MAC address associated with the IP address it wants to reach. If that information is not available, the device sends out an ARP request packet to the local network. All devices on the local network segment receive the request, but only the one with the matching IP address will respond with its MAC address. The requesting device then updates its ARP table with this new information for future communication, thus creating a new entry in the ARP table.