preboot execution environment (PXE)

Preboot Execution Environment (PXE) is an industry standard for booting network-based clients. The PXE code is located in the Basic Input/Output System( BIOS) on the motherboard of the personal computer and allows the PC client to communicate with the network server. The PXE interface can be used to remotely boot the client's operating system and to remotely start and configure the client.

Preboot Execution Environment supports Dynamic Host Configuration Protocol( DHCP), which reduces the effort of assigning IP addresses to allow the client to access the network server. In addition, PXE provides several application programming interfaces( API) that are used by the BIOS of the client PC and a standardized procedure for initializing the PXE code. In addition, PXE relies on User Datagram Protocol( UDP), Transmission Control Protocol( TCP) and Trivial File Transfer Protocol ( TFTP) for data transport and transfer.

In the PXE process, the network server is notified by the client of its PXE capability. If the network server supports PXE functionality, it sends the client a list of boot servers with available operating systems. The client searches for the appropriate boot server and uses the TFTP protocol to download and execute the appropriate file by loading the operating system. If the network server does not support PXE functionality, it ignores the client request.

The clients do not need their own operating system or hard disk for PXE functionality. In the event of an error, they can be rebooted, which assists the administrator in analyzing the error and determining the cause. The aim of the Preboot Execution Environment developed by Intel in 1996 was to reduce the Total Costs of Ownership( TCO) for the administration and setup of PC clients.