In computing, BIOS is firmware used to provide runtime services for operating systems and programs and to perform hardware initialization during the booting process. The BIOS firmware comes pre-installed on an IBM PC or IBM PC compatible's system board and exists in some UEFI-based systems to maintain compatibility with operating systems that do not support UEFI native operation. The name originates from the Basic Input/Output System used in the CP/M operating system in 1975. The BIOS originally proprietary to the IBM PC has been reverse engineered by some companies looking to create compatible systems. The interface of that original system serves as a de facto standard.
In computing, booting is the process of starting a computer as initiated via hardware such as a button or by a software command. After it is switched on, a computer's central processing unit (CPU) has no software in its main memory, so some process must load software into memory before it can be executed. This may be done by hardware or firmware in the CPU, or by a separate processor in the computer system.
Trivial File Transfer Protocol (TFTP) is a simple lockstep File Transfer Protocol which allows a client to get a file from or put a file onto a remote host. One of its primary uses is in the early stages of nodes booting from a local area network. TFTP has been used for this application because it is very simple to implement.
Internet Small Computer Systems Interface or iSCSI is an Internet Protocol-based storage networking standard for linking data storage facilities. iSCSI provides block-level access to storage devices by carrying SCSI commands over a TCP/IP network. iSCSI facilitates data transfers over intranets and to manage storage over long distances. It can be used to transmit data over local area networks (LANs), wide area networks (WANs), or the Internet and can enable location-independent data storage and retrieval.
The Bootstrap Protocol (BOOTP) is a computer networking protocol used in Internet Protocol networks to automatically assign an IP address to network devices from a configuration server. The BOOTP was originally defined in RFC 951 published in 1985.
In computing, the Preboot eXecution Environment, PXE specification describes a standardized client–server environment that boots a software assembly, retrieved from a network, on PXE-enabled clients. On the client side it requires only a PXE-capable network interface controller (NIC), and uses a small set of industry-standard network protocols such as DHCP and TFTP.
A bootloader, also spelled as boot loader or called boot manager and bootstrap loader, is a computer program that is responsible for booting a computer.
In computing, Unified Extensible Firmware Interface is a specification that defines the architecture of the platform firmware used for booting the computer hardware and its interface for interaction with the operating system. Examples of firmware that implement the specification are AMI Aptio, Phoenix SecureCore, TianoCore EDK II, InsydeH2O. UEFI replaces the BIOS which was present in the boot ROM of all personal computers that are IBM PC compatible, although it can provide backwards compatibility with the BIOS using CSM booting. Intel developed the original Extensible Firmware Interface (EFI) specification. Some of the EFI's practices and data formats mirror those of Microsoft Windows. In 2005, UEFI deprecated EFI 1.10.
Linux Terminal Server Project (LTSP) is a free and open source terminal server for Linux that allows many people to simultaneously use the same computer. Applications run on the server with a terminal known as a thin client handling input and output. Generally, terminals are low-powered, lack a hard disk and are quieter and more reliable than desktop computers because they do not have any moving parts.
A diskless node is a workstation or personal computer without disk drives, which employs network booting to load its operating system from a server.
An Option ROM for the PC platform is a piece of firmware that resides in ROM on an expansion card, which gets executed to initialize the device and (optionally) add support for the device to the BIOS. In its usual use, it is essentially a driver that interfaces between the BIOS API and hardware. Technically, an option ROM is firmware that is executed by the BIOS after POST and before the BIOS boot process, gaining complete control of the system and being generally unrestricted in what it can do. The BIOS relies on each option ROM to return control to the BIOS so that it can either call the next option ROM or commence the boot process. For this reason, it is possible for an option ROM to keep control and preempt the BIOS boot process. The BIOS generally scans for and initializes option ROMs in ascending address order at 2 KB address intervals within two different address ranges above address C0000h in the conventional (20-bit) memory address space; later systems may also scan additional address ranges in the 24-bit or 32-bit extended address space.
NetBoot was a technology from Apple which enabled Macs with capable firmware to boot from a network, rather than a local hard disk or optical disc drive. NetBoot is a derived work from the Bootstrap Protocol (BOOTP), and is similar in concept to the Preboot Execution Environment. The technology was announced as a part of the original version of Mac OS X Server at Macworld Expo on 5 January 1999. NetBoot has continued to be a core systems management technology for Apple, and has been adapted to support modern Mac Intel machines. NetBoot, USB, and FireWire are some of the external volume options for operating system re-install. NetBoot is not supported on newer Macs with T2 security chip or Apple silicon.
The booting process of Windows NT is the process run to start Windows NT. The process has been changed between releases, with the biggest changes being made with Windows Vista. In versions before Vista, the booting process begins when the BIOS loads the Windows NT bootloader, NTLDR. Starting with Vista, the booting process begins with either the BIOS or UEFI load the Windows Boot Manager, which replaces NTLDR as the bootloader. Next, the bootloader starts the kernel, which starts the session manager, which begins the login process. Once the user is logged in, File Explorer, the graphical user interface used by Windows NT, is started.
Remote Initial Program Load is a protocol for starting a computer and loading its operating system from a server via a network. Such a server runs a network operating system such as LAN Manager, LAN Server, Windows NT Server, Novell NetWare, LANtastic, Solaris or Linux.
RIS, Remote Installation Services is a Microsoft-supplied server that allows PXE BIOS-enabled computers to remotely execute boot environment variables.
The EFIsystem partition or ESP is a partition on a data storage device that is used by computers having the Unified Extensible Firmware Interface (UEFI). When a computer is booted, UEFI firmware loads files stored on the ESP to start installing operating systems and various utilities.
Intel Active Management Technology (AMT) is hardware and firmware for remote out-of-band management of select business computers, running on the Intel Management Engine, a microprocessor subsystem not exposed to the user, intended for monitoring, maintenance, updating, and repairing systems. Out-of-band (OOB) or hardware-based management is different from software-based management and software management agents.
Windows Deployment Services (WDS) is a deprecated component of the Windows Server operating system that enables centralized, network-based deployment of operating systems to bare-metal computers. It is the successor to Remote Installation Services (RIS). WDS officially supports remote deployment of Windows Vista and later, as well as Windows Server 2008 and later. However, because WDS uses disk imaging, in particular the Windows Imaging Format (WIM), it could deploy virtually any operating system. This is in contrast with its predecessor, RIS, which was a method of automating the installation process.
gPXE is an open-source Preboot eXecution Environment (PXE) client firmware implementation and bootloader derived from Etherboot. It can be used to enable computers without built-in PXE support to boot from the network, or to extend an existing client PXE implementation with support for additional protocols. While standard PXE clients use TFTP to transfer data, gPXE client firmware adds the ability to retrieve data through other protocols like HTTP, iSCSI and ATA over Ethernet (AoE), and can work with Wi-Fi rather than requiring a wired connection.
iPXE is an open-source implementation of the Preboot eXecution Environment (PXE) client software and bootloader, created in 2010 as a fork of gPXE. It can be used to enable computers without built-in PXE capability to boot from the network, or to provide additional features beyond what built-in PXE provides.
