LwIP
Encyclopedia
lwIP is a widely used open source
TCP/IP stack designed for embedded system
s. lwIP was originally developed by Adam Dunkels
at the Swedish Institute of Computer Science
and is now developed and maintained by a world wide network of developers led by Kieran Mansley.
lwIP is used by many manufacturers of embedded systems. Examples include Altera
(in the Nios II
operating system
), Analog Devices
(for the Blackfin
DSP
chip), Xilinx
and Honeywell
(for some of their FAA certified avionics systems).
The focus of the lwIP TCP/IP implementation is to reduce resource usage while still having a full scale TCP. This makes lwIP suitable for use in embedded systems with tens of kilobytes of free RAM and room for around 40 kilobytes of code ROM.
Open source
The term open source describes practices in production and development that promote access to the end product's source materials. Some consider open source a philosophy, others consider it a pragmatic methodology...
TCP/IP stack designed for embedded system
Embedded system
An embedded system is a computer system designed for specific control functions within a larger system. often with real-time computing constraints. It is embedded as part of a complete device often including hardware and mechanical parts. By contrast, a general-purpose computer, such as a personal...
s. lwIP was originally developed by Adam Dunkels
Adam Dunkels
Adam Dunkels, Ph.D., is a Swedish software engineer, researcher and co-founder of the Networked Embedded Systems Group at the Swedish Institute of Computer Science in Kista, Sweden. His research is mainly focused on networking technology and distributed communication for small embedded devices and...
at the Swedish Institute of Computer Science
Swedish Institute of Computer Science
The Swedish Institute of Computer Science, SICS, is an independent non-profit research organization with a research focus on applied computer science. The institute carries out research in a number of areas, including networked embedded systems, future Internet technologies, large scale...
and is now developed and maintained by a world wide network of developers led by Kieran Mansley.
lwIP is used by many manufacturers of embedded systems. Examples include Altera
Altera
Altera Corporation is a Silicon Valley manufacturer of PLDs . The company offered its first programmable logic device in 1984. PLDs can be reprogrammed during the design cycle as well as in the field to perform multiple functions, and they support a fairly fast design process...
(in the Nios II
Nios II
Nios II is a 32-bit embedded-processor architecture designed specifically for the Altera family of FPGAs. Nios II incorporates many enhancements over the original Nios architecture, making it more suitable for a wider range of embedded computing applications, from DSP to system-control.Nios II is...
operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
), Analog Devices
Analog Devices
Analog Devices, Inc. , known as ADI, is an American multinational semiconductor company specializing in data conversion and signal conditioning technology, headquartered in Norwood, Massachusetts...
(for the Blackfin
Blackfin
The Blackfin is a family of 16- or 32-bit microprocessors developed, manufactured and marketed by Analog Devices. The family is characterized by their built-in, fixed-point digital signal processor functionality supplied by 16-bit Multiply–accumulates , accompanied on-chip by a small and...
DSP
Digital signal processor
A digital signal processor is a specialized microprocessor with an architecture optimized for the fast operational needs of digital signal processing.-Typical characteristics:...
chip), Xilinx
Xilinx
Xilinx, Inc. is a supplier of programmable logic devices. It is known for inventing the field programmable gate array and as the first semiconductor company with a fabless manufacturing model....
and Honeywell
Honeywell
Honeywell International, Inc. is a major conglomerate company that produces a variety of consumer products, engineering services, and aerospace systems for a wide variety of customers, from private consumers to major corporations and governments....
(for some of their FAA certified avionics systems).
The focus of the lwIP TCP/IP implementation is to reduce resource usage while still having a full scale TCP. This makes lwIP suitable for use in embedded systems with tens of kilobytes of free RAM and room for around 40 kilobytes of code ROM.
lwIP features
- IPInternet ProtocolThe Internet Protocol is the principal communications protocol used for relaying datagrams across an internetwork using the Internet Protocol Suite...
(Internet Protocol) including packet forwarding over multiple network interfaces - ICMPInternet Control Message ProtocolThe Internet Control Message Protocol is one of the core protocols of the Internet Protocol Suite. It is chiefly used by the operating systems of networked computers to send error messages indicating, for example, that a requested service is not available or that a host or router could not be...
(Internet Control Message Protocol) for network maintenance and debugging - IGMP (Internet Group Management Protocol) for multicast traffic management
- UDPUser Datagram ProtocolThe User Datagram Protocol is one of the core members of the Internet Protocol Suite, the set of network protocols used for the Internet. With UDP, computer applications can send messages, in this case referred to as datagrams, to other hosts on an Internet Protocol network without requiring...
(User Datagram Protocol) including experimental UDP-lite extensions - TCPTransmission Control ProtocolThe Transmission Control Protocol is one of the core protocols of the Internet Protocol Suite. TCP is one of the two original components of the suite, complementing the Internet Protocol , and therefore the entire suite is commonly referred to as TCP/IP...
(Transmission Control Protocol) with congestion control, RTT estimation and fast recovery/fast retransmit - Specialized raw/native API for enhanced performance
- Optional Berkeley-like socket APIBerkeley socketsThe Berkeley sockets application programming interface comprises a library for developing applications in the C programming language that perform inter-process communication, most commonly for communications across a computer network....
- DNSDomain name systemThe Domain Name System is a hierarchical distributed naming system for computers, services, or any resource connected to the Internet or a private network. It associates various information with domain names assigned to each of the participating entities...
(Domain names resolver) - SNMPSimple Network Management ProtocolSimple Network Management Protocol is an "Internet-standard protocol for managing devices on IP networks. Devices that typically support SNMP include routers, switches, servers, workstations, printers, modem racks, and more." It is used mostly in network management systems to monitor...
(Simple Network Management Protocol) - DHCP (Dynamic Host Configuration Protocol)
- AUTOIP / Link-local addressLink-local addressA link-local address is an Internet Protocol address that is intended only for communications within the segment of a local network or a point-to-point connection that a host is connected to. Routers do not forward packets with link-local addresses....
(for IPv4, conforms with RFC 3927) - PPPPoint-to-Point ProtocolIn networking, the Point-to-Point Protocol is a data link protocol commonly used in establishing a direct connection between two networking nodes...
(Point-to-Point Protocol) - ARPAddress Resolution ProtocolAddress Resolution Protocol is a telecommunications protocol used for resolution of network layer addresses into link layer addresses, a critical function in multiple-access networks. ARP was defined by RFC 826 in 1982. It is Internet Standard STD 37...
(Address Resolution Protocol) for Ethernet