PowerOn Auto Provisioning (POAP) on Cisco Nexus 9000 Series Switches automates the process of upgrading software images and installing configuration files on devices being deployed for the first time. When a device with POAP boots without a startup configuration, it enters POAP mode, locates a DHCP server, and bootstraps itself with its interface IP address, gateway, and DNS server IP addresses. The device also obtains the IP address of a TFTP server and downloads a configuration script that enables the switch to download and install the appropriate software image and configuration file. Since only UDP is permitted between the Nexus 9000 switch and the server hosting the Cisco NX-OS system images, the TFTP transfer protocol, which uses UDP, must be defined1. References: * Cisco Nexus 9000 Series NX-OS Fundamentals Configuration Guide, which details the use of POAP and the requirements for network infrastructure including a DHCP server and a TFTP server