6LoWPAN (

acronym An acronym is a word or name formed from the initial components of a longer name or phrase. Acronyms are usually formed from the initial letters of words, as in ''NATO'' (''North Atlantic Treaty Organization''), but sometimes use syllables, as ...

of "

IPv6 Internet Protocol version 6 (IPv6) is the most recent version of the Internet Protocol (IP), the communication protocol, communications protocol that provides an identification and location system for computers on networks and routes traffic ...

over Low-Power Wireless

Personal Area Networks Personal may refer to: Aspects of persons' respective individualities * Privacy * Personality * Personal, personal advertisement, variety of classified advertisement used to find romance or friendship Companies * Personal, Inc., a Washington ...

") in '6LoWPAN: The Embedded Internet', Shelby and Bormann redefine the 6LoWPAN acronym as "IPv6 over lowpower wireless area networks," arguing that "Personal" is no longer relevant to the technology. was a working group of the

Internet Engineering Task Force The Internet Engineering Task Force (IETF) is a standards organization for the Internet and is responsible for the technical standards that make up the Internet protocol suite (TCP/IP). It has no formal membership roster or requirements and a ...

(IETF). It was created with the intention of applying the

Internet Protocol The Internet Protocol (IP) is the network layer communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet. IP h ...

(IP) even to the smallest devices,Mulligan, Geoff
"The 6LoWPAN architecture"
EmNets '07: Proceedings of the 4th workshop on Embedded networked sensors, ''ACM'', 2007 enabling low-power devices with limited processing capabilities to participate in the

Internet of Things The Internet of things (IoT) describes physical objects (or groups of such objects) with sensors, processing ability, software and other technologies that connect and exchange data with other devices and systems over the Internet or other comm ...

. The 6LoWPAN group defined encapsulation, header compression, neighbor discovery and other mechanisms that allow IPv6 to operate over

IEEE 802.15.4 IEEE 802.15.4 is a technical standard which defines the operation of a low-rate wireless personal area network (LR-WPAN). It specifies the physical layer and media access control for LR-WPANs, and is maintained by the IEEE 802.15 working group, ...

based networks. Although

IPv4 Internet Protocol version 4 (IPv4) is the fourth version of the Internet Protocol (IP). It is one of the core protocols of standards-based internetworking methods in the Internet and other packet-switched networks. IPv4 was the first version de ...

and IPv6 protocols do not generally care about the

physical Physical may refer to: *Physical examination In a physical examination, medical examination, or clinical examination, a medical practitioner examines a patient for any possible medical signs or symptoms of a medical condition. It generally co ...

and MAC layers they operate over, the low power devices and small packet size defined by IEEE 802.15.4 make it desirable to adapt to these layers. The base specification developed by the 6LoWPAN IETF group is (updated by with header compression, with neighbor discovery optimization, with selective fragment recovery and with smaller changes in and ). The problem statement document is . IPv6 over

Bluetooth Low Energy Bluetooth Low Energy (Bluetooth LE, colloquially BLE, formerly marketed as Bluetooth Smart) is a wireless personal area network technology designed and marketed by the Bluetooth Special Interest Group (Bluetooth SIG) aimed at novel applications in ...

using 6LoWPAN techniques is described in .

Application areas

The targets for IPv6 networking for low-power radio communication are devices that need

wireless Wireless communication (or just wireless, when the context allows) is the transfer of information between two or more points without the use of an electrical conductor, optical fiber or other continuous guided medium for the transfer. The most ...

connectivity to many other devices at lower

data rates In the pursuit of knowledge, data (; ) is a collection of discrete values that convey information, describing quantity, quality, fact, statistics, other basic units of meaning, or simply sequences of symbols that may be further interpreted. ...

for devices with very limited power consumption. One real-world example is Tado°'s individual room heating controllers. The header compression mechanisms in are used to allow IPv6 packets to travel over such networks. IPv6 is also in use on the

smart grid A smart grid is an electrical grid which includes a variety of operation and energy measures including: *Advanced metering infrastructure (of which smart meters are a generic name for any utility side device even if it is more capable e.g. a f ...

enabling

smart meter A smart meter is an electronic device that records information such as consumption of electric energy, voltage levels, current, and power factor. Smart meters communicate the information to the consumer for greater clarity of consumption beha ...

s and other devices to build a micro mesh network before sending the data back to the billing system using the IPv6 backbone. Some of these networks run over IEEE 802.15.4 radios, and therefore use the header compression and fragmentation as specified by RFC6282.

Thread

Thread is a standard from a group of more than fifty companies for a protocol running over 6LoWPAN to enable home automation. The specification is available at no cost , but paid membership is required to implement the protocol. Version 1.0 of the specification was published on 2015-10-29. The protocol will most directly compete with

Z-Wave Z-Wave is a wireless communications protocol used primarily for residential and commercial building automation. It is a mesh network using low-energy radio waves to communicate from device to device, allowing for wireless control of smart home d ...

and

Zigbee Zigbee is an IEEE 802.15.4-based specification for a suite of high-level communication protocols used to create personal area networks with small, low-power digital radios, such as for home automation, medical device data collection, and othe ...

IP.

Matter

Matter In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume. All everyday objects that can be touched are ultimately composed of atoms, which are made up of interacting subatomic partic ...

, which started as Project CHIP (Connected Home over IP) is an effort to standardize a protocol stack that could run over 6LoWPAN to enable home automation, by combining it with

DTLS Datagram Transport Layer Security (DTLS) is a communications protocol providing security to datagram-based applications by allowing them to communicate in a way designed to prevent eavesdropping, tampering, or message forgery. The DTLS protocol i ...

CoAP Constrained Application Protocol (CoAP) is a specialized Internet application protocol for constrained devices, as defined iRFC 7252 It enables those constrained devices called "nodes" to communicate with the wider Internet using similar protocols ...

and MQTT-SN

Functions

As with all link-layer mappings of IP, RFC4944 provides a number of functions. Beyond the usual differences between L2 and L3 networks, mapping from the IPv6 network to the IEEE 802.15.4 network poses additional design challenges (see for an overview).

Adapting the packet sizes of the two networks

IPv6 requires the link

maximum transmission unit In computer networking, the maximum transmission unit (MTU) is the size of the largest protocol data unit (PDU) that can be communicated in a single network layer transaction. The MTU relates to, but is not identical to the maximum frame size that ...

(MTU) to be at least 1280 octets. In contrast, IEEE 802.15.4's standard

frame A frame is often a structural system that supports other components of a physical construction and/or steel frame that limits the construction's extent. Frame and FRAME may also refer to: Physical objects In building construction *Framing (con ...

size is 127 octets. A maximum frame overhead of 25 octets and an optional but highly recommended security feature at the link layer poses an additional overhead of up to 21 octets are for AES-CCM-128. This leaves only 81 octets for the upper layers. Since this is so much less than 1280, 6LowPAN defines a fragmentation and reassembly layer. Further, the standard IPv6 Header is 40 octets long, so header compression is defined as well.

Address resolution

IPv6 nodes are assigned 128 bit

IP address An Internet Protocol address (IP address) is a numerical label such as that is connected to a computer network that uses the Internet Protocol for communication.. Updated by . An IP address serves two main functions: network interface ident ...

es in a hierarchical manner, through an arbitrary length network prefix. IEEE 802.15.4 devices may use either of IEEE 64 bit extended addresses or, after an association event, 16 bit addresses that are unique within a PAN. There is also a PAN-ID for a group of physically collocated IEEE 802.15.4 devices.

Differing device designs

devices are intentionally constrained in form factor to reduce costs (allowing for large-scale network of many devices), reduce power consumption (allowing battery powered devices) and allow flexibility of installation (e.g. small devices for body-worn networks). On the other hand, wired nodes in the IP domain are not constrained in this way; they can be larger and make use of mains power supplies.

Differing focus on parameter optimization

IPv6 nodes are geared towards attaining high speeds.

Algorithm In mathematics and computer science, an algorithm () is a finite sequence of rigorous instructions, typically used to solve a class of specific Computational problem, problems or to perform a computation. Algorithms are used as specificat ...

s and

protocol Protocol may refer to: Sociology and politics * Protocol (politics), a formal agreement between nation states * Protocol (diplomacy), the etiquette of diplomacy and affairs of state * Etiquette, a code of personal behavior Science and technolog ...

s implemented at the higher layers such as TCP kernel of the

TCP/IP The Internet protocol suite, commonly known as TCP/IP, is a framework for organizing the set of communication protocols used in the Internet and similar computer networks according to functional criteria. The foundational protocols in the suit ...

are optimized to handle typical network problems such as congestion. In IEEE 802.15.4-compliant devices, energy conservation and code-size optimization remain at the top of the agenda.

Adaptation layer for interoperability and packet formats

An adaptation mechanism to allow interoperability between IPv6 domain and the IEEE 802.15.4 can best be viewed as a layer problem. Identifying the functionality of this layer and defining newer packet formats, if needed, is an enticing research area. proposes an adaptation layer to allow the transmission of IPv6 datagrams over IEEE 802.15.4 networks.

Addressing management mechanisms

The management of addresses for devices that communicate across the two dissimilar domains of IPv6 and IEEE 802.15.4 is cumbersome, if not exhaustingly complex.

Routing considerations and protocols for mesh topologies in 6LoWPAN

Routing per se is a two phased problem that is being considered for low-power IP networking: * Mesh routing in the personal area network (PAN) space. * The routability of packets between the IPv6 domain and the PAN domain. Several routing protocols have been proposed by the 6LoWPAN community such as LOAD, DYMO-LOW, HI-LOW. However, only two routing protocols are currently legitimate for large-scale deployments: LOADng standardized by the

ITU The International Telecommunication Union is a specialized agency of the United Nations responsible for many matters related to information and communication technologies. It was established on 17 May 1865 as the International Telegraph Unio ...

under the recommendatio
ITU-T G.9903
and RPL standardized by the IETF ROLL working group.

Device and service discovery

Since IP-enabled devices may require the formation of

ad hoc network An ad hoc network refers to technologies that allow network communications on an ad hoc basis. Associated technologies include: *Wireless ad hoc network *Mobile ad hoc network * Vehicular ad hoc network ** Intelligent vehicular ad hoc network * Prot ...

s, the current state of neighboring devices and the services hosted by such devices will need to be known. IPv6 neighbour discovery extensions is an internet draft proposed as a contribution in this area.

Security

IEEE 802.15.4 nodes can operate in either secure mode or non-secure mode. Two security modes are defined in the specification in order to achieve different security objectives: Access Control List (ACL) and Secure mode

References

{{cite IETF , title = IPv6 over Low-Power Wireless Personal Area Networks (6LoWPANs): Overview, Assumptions, Problem Statement, and Goals , rfc = 2460 , sectionname = Packet Size Issues , last1 = Deering , first1 = A. , author2 = Cisco , first3 = R. , last3 = Hinden , author4 = Nokia , date = December 1998 , publisher =

IETF The Internet Engineering Task Force (IETF) is a standards organization for the Internet and is responsible for the technical standards that make up the Internet protocol suite (TCP/IP). It has no formal membership roster or requirements and a ...

, access-date = 2022-06-24 , quote = IPv6 requires that every link in the internet have an MTU of 1280 octets or greater.

External links

Internet Engineering Task Force (IETF)6lowpan.tzi.org
IPv6 Wireless networking standards