Bootstrap Protocol (BOOTP) is Networking Protocol that is used to assign dynamic IP address to workstations. BOOTP replaced RARP which has limitations of sending additional network configuration data apart from IP address and couldn’t operate across subnets as it’s OSI Layer 2 based protocol.
BOOTP operates at L4 of OSI Layer and uses UDP to carry the messages between the BOOTP Server and Client requesting for IP address and other Network Configuration. BOOTP was initially used for assigning IP address for Diskless Workstations. Later BOOTP was used to assign dynamic IP addresses for any computing workstations connected to a LAN.
Apart from IP address, BOOTP provides other network configuration like DNS IP Address, Domain Name and Default Gateway IP address for the requesting clients.
BOOTP was replaced by DHCP.
Reference
RFC – 951