A DHCP client ID is an optional parameter a device can use to identify itself on a network. While some routers and other networking equipment retrieve and store this information, most rely on media access control, or MAC, addresses.
While DHCP client IDs are rarely required, they can make managing a network simpler by identifying individual computers in a human-readable format. Network administrators don't have to look up individual MAC addresses.
In contrast to older networking technology, DHCP makes connecting to a network simpler. The client computer doesn't have to request a particular IP address; instead, the DHCP server provides one. For publicly accessible networks, this flexibility allows for quick connections.