What is 'Gratuitous ARP'? Why is it needed?

1). The form that a piece of data takes at any layer is called a 2). By sending smaller individual pieces from source to destination, many different conversations can be interleaved on the network, called 3). When a host needs to send messages using a one-to-many delivery option, it is referred to as a 4). is disintegrated at each router and is reformed to be sent to the next hop. 5). IP address has a network portion and a portion