Cisco IOS
The Internetworking Operating System (IOS) is a family of proprietary network operating systems used on several router and network switch models manufactured by Cisco Systems. The system is a package of routing, switching, internetworking, and telecommunications functions integrated into a multitasking operating system. Although the IOS code base includes a cooperative multitasking kernel, most IOS features have been ported to other kernels, such as Linux and QNX, for use in Cisco products. Not all Cisco networking products run IOS. Exceptions include some Cisco Catalyst switches, which run IOS XE, and Cisco ASR routers, which run either IOS XE or IOS XR; both are Linux-based operating systems. For data center environments, Cisco Nexus switches (Ethernet) and Cisco MDS switches ( Fibre Channel) both run Cisco NX-OS, also a Linux-based operating system. History The IOS network operating system was created from code written by William Yeager at Stanford University, which w ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Command-line Interface
A command-line interpreter or command-line processor uses a command-line interface (CLI) to receive commands from a user in the form of lines of text. This provides a means of setting parameters for the environment, invoking executables and providing information to them as to what actions they are to perform. In some cases the invocation is conditional based on conditions established by the user or previous executables. Such access was first provided by computer terminals starting in the mid-1960s. This provided an interactive environment not available with punched cards or other input methods. Today, many users rely upon graphical user interfaces and menu-driven interactions. However, some programming and maintenance tasks may not have a graphical user interface and use a command line. Alternatives to the command-line interface include text-based user interface menus (for example, IBM AIX SMIT), keyboard shortcuts, and various desktop metaphors centered on the pointer (usual ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Command-line Interface
A command-line interpreter or command-line processor uses a command-line interface (CLI) to receive commands from a user in the form of lines of text. This provides a means of setting parameters for the environment, invoking executables and providing information to them as to what actions they are to perform. In some cases the invocation is conditional based on conditions established by the user or previous executables. Such access was first provided by computer terminals starting in the mid-1960s. This provided an interactive environment not available with punched cards or other input methods. Today, many users rely upon graphical user interfaces and menu-driven interactions. However, some programming and maintenance tasks may not have a graphical user interface and use a command line. Alternatives to the command-line interface include text-based user interface menus (for example, IBM AIX SMIT), keyboard shortcuts, and various desktop metaphors centered on the pointer (usual ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Cisco IOS XR
IOS XR is a release train of Cisco Systems' widely deployed Internetwork Operating System (IOS), used on their high-end Network Convergence System (NCS) and carrier-grade routers such as the ASR 9000 series and Carrier Routing System series of routers. Architecture According to Cisco's product literature, IOS XR shares very little infrastructure with the other IOS trains, and is instead built upon a " preemptive, memory protected, multitasking, microkernel-based operating system". The microkernel was formerly provided by QNX; versions 6.0 onwards use the Wind River Linux distribution. IOS XR aims to provide the following advantages over the earlier IOS trains: * Improved high availability (largely through support for hardware redundancy and fault containment methods such as protected memory spaces for individual processes and process restartability) * Better scalability for large hardware configurations (through a distributed software infrastructure and a two-stage ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Cisco Nexus Switches
The Cisco Nexus series switches are modular and fixed port network switches designed for the data center. Cisco Systems introduced the Nexus Series of switches on January 28, 2008. The first chassis in the Nexus 7000 family is a 10-slot chassis with two supervisor engine slots and eight I/O module slots at the front, as well as five crossbar switch, crossbar switch fabric modules at the rear. Beside the Nexus 7000 there are also other models in the Nexus range. All switches in the Nexus range run the modular NX-OS firmware/operating system on the fabric. NX-OS has some high-availability features compared to the well-known Cisco IOS. This platform is optimized for high-density 10 Gigabit Ethernet. The Nexus switching range Cisco Nexus OS Software Defined Networking (SDN) allows the same policies that govern Identity and Access Management (IAM) to dictate levels of access to applications and data through a totally converged infrastructure not possible with legacy network and syste ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Process (computing)
In computing, a process is the instance of a computer program that is being executed by one or many threads. There are many different process models, some of which are light weight, but almost all processes (even entire virtual machines) are rooted in an operating system (OS) process which comprises the program code, assigned system resources, physical and logical access permissions, and data structures to initiate, control and coordinate execution activity. Depending on the OS, a process may be made up of multiple threads of execution that execute instructions concurrently. While a computer program is a passive collection of instructions typically stored in a file on disk, a process is the execution of those instructions after being loaded from the disk into memory. Several processes may be associated with the same program; for example, opening up several instances of the same program often results in more than one process being executed. Multitasking is a method to allow ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Run To Completion Scheduling
Run-to-completion scheduling or nonpreemptive scheduling is a scheduling model in which each task runs until it either finishes, or explicitly yields control back to the scheduler. Run to completion systems typically have an event queue which is serviced either in strict order of admission by an event loop, or by an admission scheduler which is capable of scheduling events out of order, based on other constraints such as deadlines. Some preemptive multitasking scheduling systems behave as run-to-completion schedulers in regard to scheduling tasks at one particular process priority level, at the same time as those processes still preempt other lower priority tasks and are themselves preempted by higher priority tasks. See also * Deadline scheduling * Preemptive multitasking * Cooperative multitasking Cooperative multitasking, also known as non-preemptive multitasking, is a style of computer multitasking in which the operating system never initiates a context switch from a ru ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Monolithic Kernel
A monolithic kernel is an operating system architecture where the entire operating system is working in kernel space. The monolithic model differs from other operating system architectures (such as the microkernel architecture) in that it alone defines a high-level virtual interface over computer hardware. A set of primitives or system calls implement all operating system services such as process management, concurrency, and memory management. Device drivers can be added to the kernel as modules. Loadable modules Modular operating systems such as OS-9 and most modern monolithic operating systems such as OpenVMS, Linux, BSD, SunOS, AIX, and MULTICS can dynamically load (and unload) executable modules at runtime. This modularity of the operating system is at the binary (image) level and not at the architecture level. Modular monolithic operating systems are not to be confused with the architectural level of modularity inherent in server-client operating systems (and its derivat ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Embedded Event Manager
Cisco Embedded Event Manager (EEM) is a feature included in Cisco's IOS operating system (and some other Cisco OSes such as IOS-XR, IOS-XE, and NX-OS) that allow programmability and automation capabilities inside the device. EEM allows the behavior of a Cisco device to adapt to specific user requirements by allowing scripting, thresholding, proactive actions, data collection and event management inside the Cisco device itself. Using EEM, problems can be identified and resolved automatically in advance by setting event triggers (called Event Detectors) to watch for specific types of situations or thresholds, or run a set of actions periodically. Cisco embedded management family EEM is a member of a family of embedded management technologies in Cisco IOS including SNMP, NetFlow, IP SLA, Web Services Management Agent, Syslog, ESM (Embedded Syslog Manager), ERM (Embedded Resource Manager), EMM (Embedded Menu Manager), Tcl and Service Diagnostics. When a situation is detected by EE ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Command (computing)
In computing, a command is a directive to a computer program to perform a specific task. It may be issued via a command-line interface, such as a shell, or as input to a network service as part of a network protocol, or as an event in a graphical user interface triggered by the user selecting an option in a menu. Specifically, the term ''command'' is used in imperative computer languages. The name arises because statements in these languages are usually written in a manner similar to the imperative mood used in many natural languages. If one views a statement in an imperative language as being like a sentence in a natural language, then a command is generally like a verb in such a language. Many programs allow specially formatted arguments, known as flags or options, which modify the default behaviour of the program, while further arguments may provide objects, such as files, to act on. As an analogy to a natural language, the flags are adverbs, while the other arguments are o ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Kalpana (company)
Kalpana was a computer-networking equipment manufacturer located in Silicon Valley which operated during the 1980s and 1990s. Its co-founders, Vinod Bhardwaj, an entrepreneur of Indian origin,Network world website Network website and Larry Blair named the company after Bhardwaj's wife, Kalpana, whose name means "imagination" in . was Kalpana's vice president of prod ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Stanford University
Stanford University, officially Leland Stanford Junior University, is a private research university in Stanford, California. The campus occupies , among the largest in the United States, and enrolls over 17,000 students. Stanford is considered among the most prestigious universities in the world. Stanford was founded in 1885 by Leland and Jane Stanford in memory of their only child, Leland Stanford Jr., who had died of typhoid fever at age 15 the previous year. Leland Stanford was a U.S. senator and former governor of California who made his fortune as a railroad tycoon. The school admitted its first students on October 1, 1891, as a coeducational and non-denominational institution. Stanford University struggled financially after the death of Leland Stanford in 1893 and again after much of the campus was damaged by the 1906 San Francisco earthquake. Following World War II, provost of Stanford Frederick Terman inspired and supported faculty and graduates' entrepreneu ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
William Yeager
William "Bill" Yeager (born June 16, 1940, San Francisco) is an American engineer. He is best known for being the inventor of a packet-switched, "Ships in the Night," multiple-protocol router in 1981, during his 20-year tenure at Stanford's Knowledge Systems Laboratory as well as the Stanford University Computer Science department. The code routed Parc Universal Packet (PUP), XNS, IP and CHAOSNet. The router used Bill's Network Operating System (NOS). The NOS also supported the EtherTIPS that were used throughout the Stanford LAN for terminal access to both the LAN and the Internet. This code was licensed by Cisco Systems in 1987 and comprised the core of the first Cisco IOS. This provided the groundwork for a new, global communications approach. He is also known for his role in the creation of the IMAP mail protocol. In 1984 he conceived of a client/server protocol, designed its functionality, applied for and received the grant money for its implementation. In 1985 Mark Crisp ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |