A network processor is an integrated circuit

Integrated circuit

An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material...

 which has a feature set specifically targeted at the networking application domain.

Network processors are typically software programmable devices and would have generic characteristics similar to general purpose central processing unit

Central processing unit

The central processing unit is the portion of a computer system that carries out the instructions of a computer program, to perform the basic arithmetical, logical, and input/output operations of the system. The CPU plays a role somewhat analogous to the brain in the computer. The term has been in...

s that are commonly used in many different types of equipment and products.

History of development

In modern telecommunications network

Telecommunications network

A telecommunications network is a collection of terminals, links and nodes which connect together to enable telecommunication between users of the terminals. Networks may use circuit switching or message switching. Each terminal in the network must have a unique address so messages or connections...

s, information (voice, video, data) is now transferred as packet data (termed packet switching

Packet switching

Packet switching is a digital networking communications method that groups all transmitted data – regardless of content, type, or structure – into suitably sized blocks, called packets. Packet switching features delivery of variable-bit-rate data streams over a shared network...

) rather than previously in older telecommunications networks as analog signal

Analog signal

An analog or analogue signal is any continuous signal for which the time varying feature of the signal is a representation of some other time varying quantity, i.e., analogous to another time varying signal. It differs from a digital signal in terms of small fluctuations in the signal which are...

s such as in the public switched telephone network

Public switched telephone network

The public switched telephone network is the network of the world's public circuit-switched telephone networks. It consists of telephone lines, fiber optic cables, microwave transmission links, cellular networks, communications satellites, and undersea telephone cables, all inter-connected by...

 (PSTN) or analog TV/Radio

Radio

Radio is the transmission of signals through free space by modulation of electromagnetic waves with frequencies below those of visible light. Electromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space...

 networks. The processing of these packets has resulted in the creation of integrated circuit

Integrated circuit

An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material...

s (IC) that are optimised to deal with this form of packet data. Network Processors have specific features or architectures that are provided to enhance and optimise packet processing within these networks.

Network processors have evolved into ICs with specific functions. This evolution has resulted in more complex and more flexible ICs being created. The newer circuits are programmable and thus allow a single hardware

Computer hardware

Personal computer hardware are component devices which are typically installed into or peripheral to a computer case to create a personal computer upon which system software is installed including a firmware interface such as a BIOS and an operating system which supports application software that...

 IC design to undertake a number of different functions, where the appropriate software is installed.

Network processors are used in the manufacture of many different types of network equipment

Networking hardware

Networking hardware typically refers to equipment facilitating the use of a computer network. Typically, this includes routers, switches, hubs, gateways, access points, network interface cards, Networking cables, network bridges, modems, ISDN adapters, firewalls and other equipments.In the most...

 such as:

• Routers, software router
  Software router
  Software router is a term denoting a computer or a PC designated to do the task of routing packets between networks. Because real hardware routers are costly , this technique of modifying the PC and using it as a router is desired...
  
  s and switches
  Network switch
  A network switch or switching hub is a computer networking device that connects network segments.The term commonly refers to a multi-port network bridge that processes and routes data at the data link layer of the OSI model...
  
  
• Firewalls
• Session Border Controller
  Session Border Controller
  A session border controller is a device regularly deployed in Voice over Internet Protocol networks to exert control over the signaling and usually also the media streams involved in setting up, conducting, and tearing down telephone calls or other interactive media communications.SBC's original...
  
  s
• Intrusion detection devices
• Intrusion prevention devices
• Network monitoring
  Network monitoring
  The term network monitoring describes the use of a system that constantly monitors a computer network for slow or failing components and that notifies the network administrator in case of outages...
  
   systems

Generic functions

In the generic role as a packet processor, a number of optimised features or functions are typically present in a network processor, these include:

• Pattern matching - the ability to find specific patterns of bits or bytes within packets in a packet stream.
• Key lookup for example, address lookup - the ability to quickly undertake a database lookup using a key (typically an address on a packet) to find a result, typically routing
  Routing
  Routing is the process of selecting paths in a network along which to send network traffic. Routing is performed for many kinds of networks, including the telephone network , electronic data networks , and transportation networks...
  
   information.
• Computation
• Data bitfield manipulation - the ability to change certain data fields contained in the packet as it is being processed.
• Queue management - as packets are received, processed and scheduled to be sent onwards, they are stored in queues.
• Control processing - the micro operations of processing a packet are controlled at a macro level which involves communication and orchestration with other nodes in a system.
• Quick allocation and re-circulation of packet buffers.

Architectural paradigms

In order to deal with high data-rates, several architectural paradigms have been commonly used:

• Pipeline of processors - each stage of the pipeline consisting of an entire processor performing one of the functions listed above.
• Parallel processing
  Parallel processing
  Parallel processing is the ability to carry out multiple operations or tasks simultaneously. The term is used in the contexts of both human cognition, particularly in the ability of the brain to simultaneously process incoming stimuli, and in parallel computing by machines.-Parallel processing by...
  
   with multiple processors, often including multithreading.
• specialized microcode
  Microcode
  Microcode is a layer of hardware-level instructions and/or data structures involved in the implementation of higher level machine code instructions in many computers and other processors; it resides in special high-speed memory and translates machine instructions into sequences of detailed...
  
  d engines to more efficiently accomplish the tasks at hand.
• recently, multicore
  Multi-core (computing)
  A multi-core processor is a single computing component with two or more independent actual processors , which are the units that read and execute program instructions...
  
  d architectures are used for higher layers (L4-L7), application processing.

Additionally, traffic management, which is a critical element in L2-L3 network processing and used to be executed by a variety of co-processors, becomes in integral part of the network processor architecture, and a substantial part of its silicon area ("real estate") is devoted to the integrated traffic manager

Applications

Using the generic function of the network processor, a software program implements an application that the network processor executes, resulting in the piece of physical equipment performing a task or providing a service. Some of the applications types typically implemented as software running on network processors are:

• Packet or frame discrimination and forwarding, that is, the basic operation of a router or switch
  Network switch
  A network switch or switching hub is a computer networking device that connects network segments.The term commonly refers to a multi-port network bridge that processes and routes data at the data link layer of the OSI model...
  
  .
• Quality of service
  Quality of service
  The quality of service refers to several related aspects of telephony and computer networks that allow the transport of traffic with special requirements...
  
   (QoS) enforcement - identifying different types or classes of packets and providing preferential treatment for some types or classes of packet at the expense of other types or classes of packet.
• Access Control functions - determining whether a specific packet or stream of packets should be allowed to traverse the piece of network equipment.
• Encryption
  Encryption
  In cryptography, encryption is the process of transforming information using an algorithm to make it unreadable to anyone except those possessing special knowledge, usually referred to as a key. The result of the process is encrypted information...
  
   of data streams - built in hardware-based encryption engines allow individual data flows to be encrypted by the processor.
• TCP offload
  TCP Offload Engine
  TCP offload engine or TOE is a technology used in network interface cards to offload processing of the entire TCP/IP stack to the network controller...
  
   processing

See also

• Content processor
  Content processor
  Content processors are sometimes confused with network processors that inspect the packet payload of an IP packet travelling through a computer network. These components allow for the design and deployment of next-generation networking systems that can make packet or message processing decisions...
  
  
• Multi core Processor
  Multi-core (computing)
  A multi-core processor is a single computing component with two or more independent actual processors , which are the units that read and execute program instructions...
  
  
• Knowledge based processor
  Knowledge-based processor
  Knowledge-based processors are used for processing packets in computer networks. Knowledge-based processors are essential for the long term success of the IPv6 . The buildout of the IPv6 network is inevitable as it provides the means to an improved and secure networking system...
  
  
• Active networking
  Active Networking
  Active networking is a communication pattern that allows packets flowing through a telecommunications network to dynamically modify the operation of the network.- How it works :...
  
  
• Computer engineering
  Computer engineering
  Computer engineering, also called computer systems engineering, is a discipline that integrates several fields of electrical engineering and computer science required to develop computer systems. Computer engineers usually have training in electronic engineering, software design, and...
  
  
• Internet
  Internet
  The Internet is a global system of interconnected computer networks that use the standard Internet protocol suite to serve billions of users worldwide...
  
  
• List of defunct Network Processor companies
• Network Processing Forum
  Network Processing Forum
  The Network Processing Forum was organized to facilitate and accelerate the development of next-generation networking and telecommunications products based on network processing technologies. The NPF was merged into the Optical Internetworking Forum in June 2006. The NPF produces Hardware,...
  
  
• Queueing theory
  Queueing theory
  Queueing theory is the mathematical study of waiting lines, or queues. The theory enables mathematical analysis of several related processes, including arriving at the queue, waiting in the queue , and being served at the front of the queue...