6Lo Working Group H. Wang Internet Draft P. Wang Interned status: Standards Track J. Zou Expires: March 19, 2016 X.Y. Wei Chongqing University of Posts and Telecommunications September 18, 2015 Transmission of IPv6 Packets over WIA-PA Networks draft-wang-6lo-wiapa-03 Abstract This document describes an Internet Protocol Version 6 (IPv6) packet transmission scheme for Wireless Networks for Industrial Automation- Process Automation (WIA-PA) networks. According to the specific demands of WIA-PA networks, the document proposes the improved WIA- PA protocol stack architecture for IPv6 technology, and the transmission format of IPv6 packets for WIA-PA networks. Furthermore, based on the characteristics of WIA-PA networks, the IPv6 address auto-configuration method is also proposed. Status of this Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on March 19, 2016. Copyright Notice Copyright (c) 2015 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents Wang, et al. Expires March 19, 2016 [Page 1] Internet-Draft IPv6 over WIA-PA September 2015 (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction ................................................. 3 1.1. Requirements Notation ................................... 4 1.2. Terms Uesd .............................................. 4 2. WIA-PA Standard .............................................. 4 2.1. WIA-PA Network Topology ................................. 5 2.2. WIA-PA Protocol Architecture ............................ 5 2.3. Address Types of WIA-PA Networks ........................ 7 3. Specification of IPv6 over WIA-PA Networks ................... 7 3.1. Protocol Stack .......................................... 7 3.2. Network Layer Frame Format .............................. 9 3.2.1. Network Layer Frame Format ......................... 9 3.2.2. Network Layer Command Frame ....................... 10 3.2.3. Transmission Format of IPv6 Packets ............... 11 3.3. Stateless Address Auto-Configuration Scheme ............ 12 3.4. Multicast Address Conversion Method .................... 14 4. IANA Considerations ......................................... 15 5. Security Considerations ..................................... 15 6. Conclusions ................................................. 16 7. Acknowledgments ............................................. 16 8. References .................................................. 16 8.1. Normative References ................................... 16 8.2. Informative References ................................. 16 8.3. External Informative References ........................ 17 Authors' Addresses ............................................. 17 Wang, et al. Expires March 19, 2016 [Page 2] Internet-Draft IPv6 over WIA-PA September 2015 1. Introduction It has been well known that Wireless Networks for Industrial Automation-Process Automation (WIA-PA) standard became the national standard of China, as well as the international standard approved by the International Electrotechnical Commission (IEC) in 2011. WIA-PA is an industrial wireless network standard towards industrial process automation, which consists of host, gateway, routing, field devices and handheld devices. WIA-PA networks have been widely used in factories, mines, smart home, intelligent transportation and all scenes related to the Internet of Things. Internet Protocol Version 6 (IPv6) is designed by Internet Engineering Task Force (IETF) with the advantage of high security, good mobility, address auto- configuration and abundant address resources. Recently, there has been a considerable interest in the transmission of IPv6 packets in industrial wireless sensor networks. For the research on the IPv6 key technologies and standards, IETF sets up the corresponding working groups. For instance, 6lo working group, which is devoted to applying IPv6 technology to resource-limited networks, and IPv6- based Low-power Personal Area Network (6LoWPAN) protocol has been the main standard of IPv6 application for wireless sensor networks. There exists a trend to apply IP technology to field devices for industrial applications, without a doubt, it also meets the demand of market. In 2013, ZigBee Alliance published the ZigBee IP specification, which makes a great contribution to connecting wireless sensor networks to Internet seamlessly via IPv6 technology. The network layer of ISA100.11a standard published by Industry Subversive Alliance (ISA) International Society of Automation has been fully compatible with 6LowPAN technology. In addition, Highway Addressable Remote Transducer (HART) fund published Wireless HART standard, and introduced the latest HART function HART-IP in Hanover Industrial Fair in 2014. Nevertheless, in China, none of the key technology of WIA-PA standard is related to IPv6, and it is rare to discuss IPv6 for WIA-PA networks abroad. It is important to realize that through IPv6 technology, we can achieve the interconnection between WIA-PA networks and Internet. For the Internet, a variety of technologies and mature applications can be extended to WIA-PA networks directly, and for WIA-PA networks, we can extend the range of transmission among industrial devices to all over the world. [RFC4944] has defined the transmission of IPv6 packets on IEEE 802.15.4. The WIA-PA standard based on IEEE 802.15.4 has been used extensively in industrial process measurement, monitoring and surveillance. In [RFC4944], IPv6 technology can be applied to support the transmission of IPv6 packets over WIA-PA networks. Wang, et al. Expires March 19, 2016 [Page 3] Internet-Draft IPv6 over WIA-PA September 2015 The aim of this document is to introduce the IPv6 transmission over WIA-PA networks. 1.1. Requirements Notation The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. 1.2. Terms Uesd WIA-PA: ''Wireless Networks for Industrial Automation-Process Automation'', a Chinese industrial wireless specification, is passed by 96% of IEC(International Electrotechnical Commission) members, and formally released as IEC/PAS 62601 standard document. IPv6: Internet Protocol Version 6 IEC: International Electrotechnical Commission IETF: Internet Engineering Task Force IEEE: Institute of Electrical and Electronic Engineers 6LoWPAN: IPv6-based Low-power Personal Area Network ISA: Industry Subversive Alliance HART: Highway Addressable Remote Transducer OSI: Open System Interconnect Reference Model MAC: Medium Access Control TDMA: Time Division Multiple Access CSMA: Carrier Sense Multiple Access PANID: Personal Area Network ID 2. WIA-PA Standard This section provides a brief overview of WIA-PA standard. We will introduce its network topology, protocol architecture and address types. Wang, et al. Expires March 19, 2016 [Page 4] Internet-Draft IPv6 over WIA-PA September 2015 2.1. WIA-PA Network Topology WIA-PA network topology SHOULD have two layers and it is a combination of star topology and mesh topology. The first layer is a MESH network, which is made up of gateways and routing nodes and can enhance robustness of WIA-PA networks. Moreover, WIA-PA networks also define redundancy gateways and redundancy routings, which enhances the reliability and self-healing capacity of the network. The second layer is a star network, which consists of routing nodes and field devices, and it is easy for network maintenance and management due to the relatively simple topology. And the WIA-PA network topology is shown in Figure 1. Host | | | | Node Gateway Node \ / \ / \ / \ / Router Router / | \ / | \ / | \ / | \ Node | \ / | Node | \ / | | / | | / \ | Node | / \ | Node \ | / \ | / \ | / \ | / Router ------- Router-----------Handheld / \ / \ Node Node Figure 1: WIA-PA Network Topology 2.2. WIA-PA Protocol Architecture WIA-PA network protocol follows OSI reference model, however, it only defines data link layer, network layer and application layer, physical layer and MAC layer are based on IEEE 802.15.4. And The WIA-PA network protocol stack is shown here: Wang, et al. Expires March 19, 2016 [Page 5] Internet-Draft IPv6 over WIA-PA September 2015 ------------+---------------------------------+ +--------------------------------------------+ | User Application Process | | Device Management Application Process | +------------+ +----------------+ +-------------------+ +----------------------+ | User | | User | |Network Management | | Security Management | |Application |...| Application | +-------------------+ +----------------------+ Application | Object 1 | | Object n | | | +------------+ +----------------+ | +---------------+ | | +-----------+ | | | | | Layer +--------+ ASLDE-SAP +------------+--+----+ ASLDE-SAP +-------------+ | +--------+ +--------------------+ +-----------+ | | | +-----------+ +---------------+ | | | +-------------+----------------+ +-----------+----------+ +-+-+-+ | |Communication| Polymerization |Application|Application|Management| |ASLME| | | | and | | Layer | | | | | | Mode |Depolymerization| Sublayer | Security | Services | |-SAP | | +-------------+----------------+ +-----------+----------+ +-+-+-+ | | +----------+ +-------------+ | | | ------------+--------+ NLDE-SAP +---------------------+ NLME-SAP +-------------+ | | +--------+ +---------------------+ +-------------+ | + - + | | +----------+ +-------------+ | | | | | +------------+---------+ +-------------+----------++-+-+-+ | M | | Network | Addressing | Router | Network Layer |Fragmentation|Management||NMLE | | | | Layer +------------+---------+ | and | || | | I | | | |Restructuring| Services ||-SAP | | | | +-----------------------------------------+-------------+----------++-+-+-+ | B | | | +----------+ +--------------+ | | | | | +--------+ DLDE-SAP +---------------------+ DLME-SAP +------------+ | | | | ------------+--------+ +---------------------+ +------------+ | + - + | | +----------+ +--------------+ | | | +---------------+----------+ Data +-------+--------+-----------+ +-+-+-+ | | Time |Superframe| Link | Hop | Link | Management| |DLME | | Data |Synchronization|Scheduling|Sublayer|Channel| Layer | | | | | Link +---------------+----------+ | |Security| Services | |-SAP | | Layer | +-------+--------+-----------+ +-+-+-+ | | +----------+ +--------------+ | | | +--------+ MLDE-SAP +---------------------+ MLME-SAP +------------+ +---------+ +--------+ +---------------------+ +------------+ | +----------+ +--------------+ | | IEEE 802.15.4 MAC Layer | | | ------------+---------------------------------------------------------------------+ Physical | | Layer | IEEE 802.15.4 Physical Layer | ------------+---------------------------------------------------------------------+ Figure 2: Protocol Architecture of WIA-PA Networks Wang, et al. Expires March 19, 2016 [Page 6] Internet-Draft IPv6 over WIA-PA September 2015 2.3. Address Types of WIA-PA Networks As for address types, in WIA-PA networks, all devices MUST have globally unique EUI-64 long addresses and 16-bit short addresses. Devices are assigned EUI-64 long addresses by manufacturers and 16- bit short addresses by host, and they communicate for one another with a short address. 3. Specification of IPv6 over WIA-PA Networks In this section, we define the specification of IPv6 packets over WIA-PA networks. WIA-PA standard has defined MESH router mechanism, aggregation/disaggregation and fragmentation/restructuring, thus for WIA-PA networks with IPv6 technology, we SHOULD NOT adopt the MESH router mechanism and the fragmentation/restructuring defined by 6LoWPAN. However, in [RFC4944] and [RFC6282], address compression and stateless address auto-configuration SHOULD be applied to WIA-PA networks. 3.1. Protocol Stack The IPv6 over WIA-PA protocol stack is shown in Figure 3. The protocol stack contains application layer, transport layer, network layer, data link layer and physical layer, and the functions of each layer are as follows: o Application layer: It defines the communication service to support the communications among a plurality of objects of distributed applications in industrial environment. For data communication service, it mainly includes three types of modes: client/server communication, publish/subscribe communication and report communication. o Transport layer: It uses the connectionless and small footprint UDP protocol, and provides the service between network layer and application layer. Meanwhile, it also completes the encapsulation and parsing of UDP packets and the establishment and destruction of UDP connection. o Network layer: It is divided into network layer upper and network layer lower, wherein the network layer upper is the Internet layer which consists of IP layer and adaptation layer. The main tasks of IP layer are IPv6 packets encapsulation, address resolution, and providing mobility support and stateless address auto-configuration, etc. IPv6 header compression mechanism and padding message values are Wang, et al. Expires March 19, 2016 [Page 7] Internet-Draft IPv6 over WIA-PA September 2015 executed in adaptation layer. Network layer lower is WIA-PA network layer, which is mainly used for the network layer of WIA-PA standard. In addition, MESH subnet routing and addressing are also achieved in Network layer lower. o Data link layer and physical layer: Both of them adopt the techniques of WIA-PA standard. Data link layer supports radio frequency (RF) channel access, and device network joining, etc. Physical layer is used for energy detection, channel selection, as well as starting and ending a RF transceiver. --------------+----------------------------------+ +-----------------------------------------+ | User Application Process | | Device Management Application Process | +-------------+ +----------------+ +-------------------+ +-------------------+ | User | | User | |Network Management | |Security Management| |Application |...| Application | +-------------------+ +-------------------+ Application | Object 1 | | Object n | | | +-------------+---+----------------+--+------------+-----------+----------+ | Layer |Communication| | Polymerization | Application |Application|Management| | | | | and | | Layer | | | | Mode | |Depolymerization| Sublayer | Security | Services | | --------------+-------------+---+----------------+---------------+-----------+----------+ | Transport | | | Layer | UDP Transport Layer | | --------------+-------------------------------------------------------------------------+ M | Internet Layer| | | /Network Layer+----------------------+ +------------+------------------+ | Upper |Address Configuration | IP Layer | Address | Adaptation | I | +----------------------+ |Compression | Layer | | Network | +------------+ | | Layer -------+-----------------------------------------+-------------------------------+ B | +--------------------+ +----------------+-----------+ | WIA-PA Network| Management Services| WIA-PA Network Layer | Fragmentation | Router | | Layer/Network +--------------------+ | /Restructuring | | | Layer Lower | +----------------+-----------+ | --------------+---------------+----------+-------------+-------+--------+-----------+---+ | | Time |Superframe| Data | Hop | Link | Management| | | Data |Synchronization|Scheduling| Link |Channel| Layer | | | | Link +---------------+----------+ Sublayer | |Security| Services | | | Layer | +-------+--------+-----------+ | | +-------------------------------------------------------------------------+ | | IEEE 802.15.4 MAC Layer | | --------------+-------------------------------------------------------------------------+ | Physical Layer| IEEE 802.15.4 Physical Layer | | --------------+-------------------------------------------------------------------------+-----+ Figure 3: IPv6 over WIA-PA Protocol Stack Wang, et al. Expires March 19, 2016 [Page 8] Internet-Draft IPv6 over WIA-PA September 2015 3.2. Network Layer Frame Format In order to introduce IPv6 technology to WIA-PA networks, we combine WIA-PA standard and IPv6 technology, adding Internet layer and transport layer to previous WIA-PA network protocol stack, where adaptation layer and IP layer MUST be included in Internet layer. 3.2.1. Network Layer Frame Format The WIA-PA network frame format with IPv6 technology is shown in Figure 4. If the command frames interact with each other, the frame format SHOULD NOT include Internet layer, transport layer and application layer, and if the IPv6 packets interact for one another, the frame format for IPv6 packets is as follows: +-------+-----------+---------------------+--------------+---------+---------------------+----+ | MAC |Data Link | WIA-PA | Internet |Transport| Application | | | Layer | Layer | Network Layer | Layer | Layer | Layer |Load| | Header| Header | Header | Header | Header | Header | | +-------+-----------+---------------------+-------+------+---------+-------+------+------+----+ | | |Network Frame Control| | | | | | | | | | +-------+-------------+ | | | | | | | | | | | Destination | | | | | | | | | | | | Address | | | | | | | | |Source |Destination| Router+-------------+Message| Other| UDP | APS |Serial|Frame |Load| |Address| Address | Field | Source |Values |Fields| Header | Frame |Number|Length| | | | | | Address | | | |Control| | | | | | | +-------------+ | | | | | | | | | | | Router ID | | | | | | | | | | +-------+-------------+ | | | | | | | | | | Other Fields | | | | | | | | +-------+-----------+---------------------+-------+------+---------+-------+------+------+----+ Figure 4: IPv6 over WIA-PA Frame Format The IPv6 packets make a modification on the frame control field of WIA-PA network layer header, which mainly defines bit5 of the frame control field. When bit5 is equal to 0, it indicates the packet MUST be a protocol data unit of WIA-PA network layer, and when bit5 is equal to 1, if package type is a WIA-PA network layer command frame, it indicates the packet MUST be an IPv6 related command frame, and if package type is a WIA-PA network layer packet, it indicates the packet MUST be an IPv6 packet then passes it to the upper layer to resolve. The revised WIA-PA network layer frame control field is shown in Figure 5. Wang, et al. Expires March 19, 2016 [Page 9] Internet-Draft IPv6 over WIA-PA September 2015 +-----------+-----------------+-----------+-----------------+---------------+--------------+ |Bit: 0-1 | 2 | 3 | 4 | 5 | 6-7 | +-----------+-----------------+-----------+-----------------+---------------+--------------+ | Packet | Fragmentation | P/S | Certification | IPv6 Packet | Retention | | Type | Flag | Flag | Flag | Flag | | +-----------+-----------------+-----------+-----------------+---------------+--------------+ Figure 5: Network Layer Frame Control Field 3.2.2. Network Layer Command Frame In order to solve the problem of nodes getting the network prefix or IPv6 address, our document defines the following five categories of IPv6 network layer command frame: 1) Enhanced IPv6 joining response command frame: The command identifier is defined as ''129'', and it SHOULD be used for IPv6 nodes to reply the access network request. Network layer frame format of the response is shown in Figure 6. According to the ways to distribute IPv6 addresses or prefixes by host, the values of response command frame related field to be different. +-------+-------------------------------------------------------------------------------------+ |Network| | | Layer | Network Layer Load | | Header| | +-------+----------+-----+------------------+--------------+---------------------+------------+ | | | | Physical Address | Short Address| IPv6 Address Option | | | Header| Command |Added| of Devices | of Devices | of Devices |IPv6 Address| | |Identifier|State| to be added | to be added | to be added | /Prefix | +-------+----------+-----+------------------+--------------+---------------------+------------+ Figure 6: Enhanced IPv6 Joining Response Command Frame 2) Query short address request command frame: The command identifier is defined as ''130'', and the packet SHOULD be used for devices to query their own short addresses according to IPv6 addresses. Its frame format is shown here: +------------------------+--------------------------------------------+ | Network Layer Header | Network Layer Load | +------------------------+-----------------------+--------------------+ | Header | Command Identifier | IPv6 Address | +------------------------+-----------------------+--------------------+ Figure 7: Query Short Address Request Command Frame 3) Query short address response command frame: The command identifier is Wang, et al. Expires March 19, 2016 [Page 10] Internet-Draft IPv6 over WIA-PA September 2015 defined as ''131'', and the packet SHOULD be used for host to send a short address query request result to devices. Its frame format is shown here: +----------------------+-------------------------------------------------------------------+ | Network Layer Header | Network Layer Load | +----------------------+------------------+-------------------+------------+---------------+ | Header |Command Identifier| Execution Results |IPv6 Address| Short Address | +----------------------+------------------+-------------------+------------+---------------+ Figure 8: Query Short Address Response Command Frame 4) Query IPv6 address request command frame: The command identifier is defined as ''132'', and the packet SHOULD be used for devices to query IPv6 addresses according to their own short addresses. Its frame format is shown here: +------------------------+--------------------------------------------+ | Network Layer Header | Network Layer Load | +------------------------+-----------------------+--------------------+ | Header | Command Identifier | Short Address | +------------------------+-----------------------+--------------------+ Figure 9: Query IPv6 Address Request Command Frame 5) Query IPv6 address response command frame: The command identifier is defined as ''133'', and the packet SHOULD be used for host to send an IPv6 address query request result to devices. Its frame format is shown here +----------------------+-------------------------------------------------------------------+ | Network Layer Header | Network Layer Load | +----------------------+------------------+-------------------+-------------+--------------+ | Header |Command Identifier| Execution Results |Short Address| IPv6 Address | +----------------------+------------------+-------------------+-------------+--------------+ Figure 10: Query IPv6 Address Response Command Frame 3.2.3. Transmission Format of IPv6 Packets For the transmission of IPv6 packets, our document combines 6LoWPAN address compression method and the ways to obtain IPv6 address to define the following four kinds of header format of Internet layer, and the format of Internet layer header is shown here: Wang, et al. Expires March 19, 2016 [Page 11] Internet-Draft IPv6 over WIA-PA September 2015 +-------+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+--------------------+ |Bit: 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | Lengthen | +-------+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+--------------------+ | FLAG | TF | NH| HLIM |CID|SAC| SAM | M |DAC| DAM | | +---------------+-------+---+-------+---+---+-------+---+---+-------+ Other Fields | | Dispatch | IPHC Basic Coding | | +-----------------------------------+-------------------------------+--------------------+ Figure 11: Internet Layer Header Format The Internet layer headers of IPv6 packets have different dispatch due to the devices use different ways to get IPv6 address. And the four different types of dispatch mentioned above are as follows: 1) If the devices communicate with extranet devices, we SHOULD use uncompressed IPv6 packets during transmission, then the Internet layer header contains dispatch and other fields, where the dispatch is ''01000001'' and other fields are the related fields of IPv6 header. 2) If the IPv6 address prefix of devices is the entire network unified prefix, the IPv6 packets are stateless compression. In this case, the Internet layer header only contains dispatch and address compression coding with the value of ''011TT1HH00110011'', where the value of ''TT'' represents IPv6 header compression about Traffic Class, and the value of ''HH'' represents IPv6 header compression about Hop Limit. 3) If is not the entire network unified prefix, the IPv6 packets are state compression, and the Internet layer header also includes dispatch and the address compression coding with the value of ''0111111001110111''. 4) If the devices use the IPv6 header compression algorithm of 6LoWPAN to partially compress IPv6 header, the Internet layer header contains dispatch, address compression coding and other fields, where other fields are the uncompressed part of IPv6 header. 3.3. Stateless Address Auto-Configuration Scheme All devices SHOULD be distributed prefixes or IPv6 addresses by host, and the process modes of devices are different due to the various distribution ways. There are three approaches as follows: 1) Unified network prefix: Host distributes a unified whole network prefix to each device, and the devices can generate IPv6 addresses with address configuration method. Then, we have the following four categories of IPv6 address: Wang, et al. Expires March 19, 2016 [Page 12] Internet-Draft IPv6 over WIA-PA September 2015 o The automatically generated IPv6 link-local address in the process of device initialization: The IPv6 link-local address SHOULD be composed by prefix and interface identifier, where the prefix is ''FE80::0'', and the interface identifier is the negation of bit7 of EUI-64 physical address. The EUI-64 link-local address is shown here: +------------------------+-----------------------+--------------------+ | Bit: 1-10 | 11-64 | 65-128 | +------------------------+-----------------------+--------------------+ | 1111111010 | 0 | EUI-64 | +------------------------+-----------------------+--------------------+ Figure 12: EUI-64 Link-local Address o The IPv6 link-local address generated by the short address distributed by gateway: The prefix is ''FE80::0'', the interface identifier is generated by the short address and the negation of bit7 of PANID. Due to the addresses are all composed by prefix and interface identifier, only difference in composition, no more reiteration here. The short address link-local address is shown here: +-----------+-------+---------+---------+------------------+---------+---------------------+ | Bit: 1-10 | 11-64 | 65-80 | 81-88 | 89-104 | 105-112 | 113-128 | +-----------+-------+---------+---------+------------------+---------+---------------------+ | 1111111010| 0 | PANID | 0 | 1111111111111110 | 0 |16-bit Short Address | +-----------+-------+---------+---------+------------------+---------+---------------------+ Figure 13: Short Address Link-local Address o The IPv6 unicast address generated by the unified whole network prefix distributed by host and EUI-64 physical address: The prefix is a unified whole network prefix distributed by host, the interface identifier is the negation of bit7 of EUI-64 physical address, and the EUI-64 unicast address is shown in Figure 14, where N is the prefix length. +------------------------+-----------------------+--------------------+ | Bit: 1-N | 64-N | 65-128 | +------------------------+-----------------------+--------------------+ | Prefix | 0 | EUI-64 | +------------------------+-----------------------+--------------------+ Figure 14: EUI-64 Unicast Address o The IPv6 unicast address generated by the unified whole network prefix distributed by host and the short address distributed by gateway: The prefix is a unified whole network prefix distributed by Wang, et al. Expires March 19, 2016 [Page 13] Internet-Draft IPv6 over WIA-PA September 2015 host, the interface identifier is generated by the short address and the negation of bit7 of PANID, and the short address unicast address is shown here: +-----------+-------+---------+---------+------------------+---------+---------------------+ | Bit: 1-N | 64-N | 65-80 | 81-88 | 89-104 | 105-112 | 113-128 | +-----------+-------+---------+---------+------------------+---------+---------------------+ | Prefix | 0 | PANID | 0 | 1111111111111110 | 0 |16-bit Short Address | +-----------+-------+---------+---------+------------------+---------+---------------------+ Figure 15: Short Address Unicast Address 2) Non-Unified network prefix: Host distributes the entire network non- uniform prefix to devices, through the prefix, devices can generate IPv6 address with address configuration method. Consequently, it can also generate four kinds of IPv6 address, and the way is consistent with the unified one. 3) IPv6 address: Host distributes IPv6 address to devices. Then, two kinds of IPv6 address can be generated, one is the IPv6 address distributed by host, the other is the IPv6 link-local address generated by EUI-64 physical address, as shown in figure 12. 3.4. Multicast Address Conversion Method In WIA-PA networks, there MUST be two types of address: EUI-64 long address and 16-bit short address. In order to achieve the conversion between WIA-PA network address and IPv6 network address, for EUI-64 long address, we complete the conversion with the use of address configuration method in [RFC4944]. And the short address is divided into broadcast address and unicast address, the unicast address uses the address configuration method in [RFC4944], the definition of broadcast address is according to the broadcast address set by WIA- PA standard and the structural properties of IPv6 multicast address. Several types of WIA-PA broadcast address are shown here: +-------------+---------------------+-----------------+-----------------+-----------------+ | Broadcast | Broadcast Address |The Whole Network| MESH Network | Gateway | |Address Types| within the Cluster |Broadcast Address|Broadcast Address|Broadcast Address| +-------------+---------------------+-----------------+-----------------+-----------------+ | Broadcast |Cluster Address x.25 | 255.255 | 255.0 | 0.255 | | Addresses | x Range: 1-254 | | | | +-------------+---------------------+-----------------+-----------------+-----------------+ Figure 16: WIA-PA Broadcast Address Wang, et al. Expires March 19, 2016 [Page 14] Internet-Draft IPv6 over WIA-PA September 2015 The IPv6 multicast address is shown in Figure 17. In [RFC4291], IPv6 multicast address defines its top eight is ''11111111''. Besides, the second field is a flag field, it is permanent when the multicast address is ''0000'', and it is temporary when ''0001''. The third field is a range field, the different values represent the different range. The broadcast address of our document is only for devices in link- local, and the range field indicates link-local when it is ''0010''. +------------+---------+-----------+---------------+ | Bit: 0-7 | 8-11 | 12-15 | 16-128 | +------------+---------+-----------+---------------+ | 11111111 | Flags | Scope | Group ID | +------------+---------+-----------+---------------+ Figure 17: IPv6 Multicast Address As shown in Figure 18, we define IPv6 broadcast address for WIA-PA networks, where the broadcast address within the cluster is ''FF12::x .FF''. Due to the broadcast address within the cluster is non-permanent distribution, thus its flag field is ''1'', and ''x'' indicates the cluster address of network, which is located in ''1- 254''. In addition, the broadcast address of entire network is ''FF02::1'', which represents all field devices from broadcast to network. The broadcast address of MESH network is ''FF02::2'', which represents all routers from broadcast to network, and the broadcast address of gateway is ''FF02::FF''. +----------------+------------------+-----------------+-----------------+-----------------+ | Broadcast |Broadcast Address |The Whole Network| MESH Network | Gateway | | Address Types |within the Cluster|Broadcast Address|Broadcast Address|Broadcast Address| +----------------+------------------+-----------------+-----------------+-----------------+ | WIA-PA Network | FF12::x. FF | FF02::1 | FF02::2 | FF02::FF | | IPv6 Broadcast | x Range: 1-254 | | | | +----------------+------------------+-----------------+-----------------+-----------------+ Figure 18: IPv6 Broadcast Address 4. IANA Considerations There are no IANA considerations related to this document. 5. Security Considerations In industrial environment, the wireless networks share the same place and time. In this case, if the security mechanism is not very brilliant, it will seriously affect the system's information security. The security mechanism is beyond the scope of this draft. Wang, et al. Expires March 19, 2016 [Page 15] Internet-Draft IPv6 over WIA-PA September 2015 6. Conclusions This document proposed a scheme which is suitable for the transmission of IPv6 packets over WIA-PA networks. Protocol architecture, IPv6 specific command frame, the transmission format of packets in adaptation layer and multicast address conversion method are all defined in this document. 7. Acknowledgments We are grateful to the authors of [RFC4944] and [RFC6282] and the members of the IETF 6LoWPAN working group. 8. References 8.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing Architecture", RFC 4291, February 2006. [RFC4944] Montenegro, G., Kushalnagar, N., Hui, J., and Culler, D., "Transmission of IPv6 Packets over IEEE 802.15.4 Networks", RFC 4944, September 2007. [RFC6282] J. Hui, Ed, "Compression Format for IPv6 Datagrams over IEEE 802.15.4-Based Networks", RFC 6282, September 2011. 8.2. Informative References [EUI-64] IEEE, "GUIIDELINES FOR 64-BIT GLOBAL IDENTIFIER (EUI-64) REGISTRATION AUTHORITY", IEEE Std http://standards.ieee.org/regauth/oui/tutorials/EUI64.html, November 2012. [I-D.ietf-6lo-btle] Nieminen, J., Savolainen, T., Isomaki, M., Patil, B., Shelby, Z., and C. Gomez, "Transmission of IPv6 Packets over BLUETOOTH Low Energy", draft-ietf-6lo-btle-00 (work in progress), November 2013. Wang, et al. Expires March 19, 2016 [Page 16] Internet-Draft IPv6 over WIA-PA September 2015 8.3. External Informative References [WIA-PA] IEC/PAS 62601 Ed.1.0[S], WIA-PA communication network and communication profile, 2009. [ISA100.11a] ISA100.11a Working Group,''Wireless systems for industrial automation: Process control and related applications,'' ISA100.11a Draft standard, September 2008. [IEEE802.15.4] IEEE Computer Society, "IEEE Std. 802.15.4-2006", June 2006. Authors' Addresses Heng Wang Chongqing University of Posts and Telecommunications 2 Chongwen Road Chongqing, 400065 China Phone: (86)-23-6248-7845 Email: wangheng@cqupt.edu.cn Ping Wang Chongqing University of Posts and Telecommunications 2 Chongwen Road Chongqing, 400065 China Phone: (86)-23-6246-1061 Email: wangping@cqupt.edu.cn Ji Zou Chongqing University of Posts and Telecommunications 2 Chongwen Road Chongqing, 400065 China Phone: (86)-23-6246-1061 Email: 976345534@qq.com Wang, et al. Expires March 19, 2016 [Page 17] Internet-Draft IPv6 over WIA-PA September 2015 Xinyu Wei Chongqing University of Posts and Telecommunications 2 Chongwen Road Chongqing, 400065 China Phone: (86)-23-6246-1061 Email: 1294945391@qq.com Wang, et al. Expires March 19, 2016 [Page 18]