- What are an EUI-48 and an EUI-64?
- How can I obtain a universally unique MAC/Ethernet address?
- I need unique numbers in my standard, what are my options?
- What costs are involved with obtaining an assignment?
- What is the difference between a publicly-listed and a privately-registered assignment?
- My company wants an additional block of addresses for our new project. Can we receive one?
- What if my company’s contact information changes after I receive the assignment?
- How can I obtain the names and assignments of those companies who have registered an assignment?
- My organization is writing a standard or specification that will include the use of the OUI. How do I make sure this is okay with the IEEE Registration Authority Committee (IEEE RAC)?
- Can I resell or distribute a segment of the assignment after I obtain it?
- Can my assignment be used with Bluetooth?
- Who can I contact if I have additional questions?
OUI, EUI-48, EUI-64, MAC ADDRESSES, CID
- What is a MA-L, MA-M, or MA-S assignment?
- What address block should I apply for?
- What is a Company ID (CID)?
- Who can apply for a Standard Group MAC Address Assignment?
- What is an Organizationally Unique Identifier (OUI)?
- Is it permissible to use the value of zero (00-00-00) as a placeholder for an OUI to be assigned later?
- What is a "company_id"?
- What is an Individual Address Block (IAB)?
- What is a 36-bit Organizationally Unique Identifier(OUI-36)?
- What standards are involved with EUI-48, EUI-64, OUI and CID assignments?
- What is an Ethertype?
- I’m developing a new protocol; can I get an Ethertype assignment?
- What are the criteria for an Ethertype assignment?
- What is an Ethertype subtype?
- What is a Vendor Specific Protocol?
- How can I obtain an Ethertype assignment?
IEEE 1451.4™-2004 Registration Activities
- What is IEEE Std 1451.4™-2004, what are its uses and how does it work?
- What are the benefits of using IEEE Std 1451.4-2004?
- What is an IEEE 1451.4 manufacturer_ID?
- What is a URN and why is it needed?
- What is a transducer electronic data sheet (TEDS)?
- What is a template?
- Who writes templates, where may they be obtained and how may I publish one?
- What is the template description language?
- How can I obtain a manufacturer ID?
- How can I obtain an assignment of a URN Block(s)?
- What are the costs involved in obtaining a manufacturer ID or URN block assignment, or in publishing a new template? What is the method of payment?
- How may I obtain the names and ID numbers of those companies who own a manufacturer ID or URN block assignment?
- May I re-sell or distribute a segment of the URN block after I obtain it?
- My company wants an additional manufacturer ID number for our new project. Can we receive one?
Provider Service Identifier Registration Activities
- What is a PSID?
- Who maintains PSID allocations?
- What is the PSID used for?
- Do I need a new PSID to be allocated to my service?
- Where can I find a list of already allocated PSIDs?
- What are testing PSIDs?
- What size PSID should I request?
- What is p-encoding?
- How many PSIDs can I request at one time?
- Can I request a specific PSID value?
- What is the process for requesting a PSID?
- What is expected of the assignee of a PSID?
- How can I learn more about PSIDs and DSRC WAVE based systems?
IEEE 802.16™ Operator ID Registration Activites
- What is an Operator ID (OpID)?
- Is an IEEE-assigned Operator ID required in order to deploy an IEEE 802.16 network?
- Why do I need an Operator ID?
- WCan I use another assignment as an IEEE 802.16 Operator ID, or vice versa?
- What is a Base Station ID?
- How can I obtain the names and ID numbers of those companies who own an IEEE 802.16 Operator ID?
- Can I re-sell the IEEE 802.16 Operator ID after I obtain it?
- How can I obtain an assignment of an IEEE 802.16™ Operator ID?
- My company needs multiple IEEE 802.16 Operator ID s for multiple networks. Can we receive them?
- My regulator requires that I use my E.212 MCC-MNC to identify my network. How can I do this with IEEE Std 802.16 and OpID?
- If my organization already has an E.212 MCC-MNC allocation, are we compelled to use it as the Operator ID with our 802.16 network? Are we disallowed from applying for an 802.16-specific OpID from the IEEE Registration Authority?
- Are there geographic restrictions on the use of an OpID?
- Are all of the OpIDs globally unique?
- If we do not apply for our own OpID to program into our base stations, will they all have the same "default" operator ID?
- When may I make use of the Public OpID Pool?
- What is the probability of duplication of a private network ID?
What are an EUI-48 and an EUI-64?
The 48-bit Extended Unique Identifier (EUI-48) and 64-bit Extended Unique Identifier (EUI-64) are globally unique identifiers used for identification of objects. Objects may be a hardware device (e.g., a network interface), a function (e.g., to identify a clock function) and similar applications. EUI-48 and EUI-64 are most commonly used for IEEE 802® universally unique MAC addresses.
EUI-48 and EUI-64 identifiers are assigned in various block sizes (MA-L, MA-M, and MA-S).
For more information, please see the tutorials on use of EUI-48 and EUI-64.(Back to top)
How can I obtain a universally unique MAC/Ethernet address?
Blocks of universally unique MAC addresses/Ethernet addresses are assigned by the IEEE Registration Authority (RA). The RA makes these assignments to customers in three (3) block sizes: (MA-L = ~16 Million addresses, MA-M = ~1 Million addresses, MA-S = 4,096 addresses). Individual (i.e. single) addresses are not available from the IEEE. A 48-bit universally unique MAC address is formally referred to as an EUI-48.A 64-bit universally unique MAC address is formally referred to as an EUI-64.There is a monetary charge made by the IEEE RA for an address block.
Once you have checked against the appropriate public listing to verify your company does not already have an assignment, you may log in or create an account to request one. If the company already has an assignment, send an e-mail to the IEEE Registration Authority requesting the contact information for the existing assignment, and then make arrangements within your company to use your existing assignment.
Once the application is completed successfully, the applicant will receive an e-mail with a tracking number and payment information. The application will be processed within 7 (US) business days after receipt of payment as long as there are no problems with the information on the application or the payment. The applicant will receive an e-mail with the assignment information once the application is processed.(Back to top)
I need unique numbers in my standard, what are my options?
Consider if an existing registry is applicable. For many needs, the OUI/CID, EUI-48 or EUI-64 may meet your requirements. If different numbers are required, the IEEE Registration Authority should be consulted before balloting
What costs are involved with obtaining an assignment?
The prices for the various assignments available from the IEEE Registration Authority may be found on the IEEE RA web site for each registry.
Select assignments may be kept confidential for an annual fee.
IEEE accepts checks (payable to IEEE Registration Authority), wire transfers, as well as major credit cards and purchase orders with approved credit applications.(Back to top)
What is the difference between a publicly-listed and a privately-registered assignment?
The difference between a public and private assignment is the format of the listing in our public listings. A public assignment lists the assignment with the company name and address. A private assignment lists the assignment with "PRIVATE" next to the number. Applicants of privately registered assignments are sent a renewal invoice annually.
My company wants an additional block of addresses for our new project. Can we receive one?
The Registration Authority requires that you use 95% of an existing MA-L or MA-M assignment before an additional number can be issued to you. You must still fully exhaust your assignment before you may use the new assignment issued to you. Assignments should not be used on a per product basis or by manufacturing location. Parent and subsidiary companies can and are heavily encouraged to share assignments. Please include a Usage Percentage in section 3 of the application. Exceptions are rarely granted.
What if my company’s contact information changes after I receive the assignment?
Please log in and update your company information. If there is a company name change due to purchase or sale please also email a press release or some details of the company name change to email@example.com. The company name change will not be uploaded to the public listing unless the press release or details are received.
How can I obtain the names and assignments of those companies who have registered an assignment?
Please see the public listings available on our web site to view public directories for each active registry.
My organization is writing a standard or specification that will include the use of the OUI. How do I make sure this is okay with the IEEE Registration Authority Committee (IEEE RAC)?
The IEEE Registration Authority requests that any organization that intends to utilize the Organizationally Unique Identifier in the standardization of a technical area that has not previously been reviewed and approved by the IEEE RAC, please contact the IEEE Registration Authority.
IEEE standards that include OUIs and other unique numbers are subject to review by the IEEE Registration Authority Committee during ballot (Mandatory Coordination).Previously reviewed and approved standards might include new applications of OUIs and identifiers derived from OUIs. Such new applications should also be reviewed by the IEEE RAC. When revised, standards should be reviewed for consistent use of current terminology.(Back to top)
Can I resell or distribute a segment of the assignment after I obtain it?
No. A parent company and a subsidiary company should share an assignment and if a company is sold, the assignment may be transferred to the new company. However, the assignment cannot be sold or distributed by anyone other than IEEE.
Can my assignment be used with Bluetooth?
An assignment of extended unique identifiers can be used with Bluetooth. Please refer to the Bluetooth website for more information.
What is a MA-L, MA-M, or MA-S assignment?
There are currently 3 different size blocks of MAC Addresses available. They are MA-L (MAC Address Block Large), MA-M (MAC Address Block Medium) and MA-S (MAC Address Block Small).
|Address Block||Previously Named||Number of Addresses||Applicable for 48-bit addresses||Applicable for 64-bit addresses|
|MA-L||OUI||2^24 (~16 Million)||Yes||Yes|
|MA-M||--||2^20 (~1 Million)||Yes||Yes|
|MA-S||OUI-36(encompasses IAB Assignments)||2^12 (4,096)||Yes||Yes|
What address block should I apply for?
The Registration Authority encourages organizations/companies to apply for the smallest block that will meet their needs. Example: If your organization plans to only create or distribute 500,000 devices, a MA-M assignment would suit your needs more appropriately than a MA-S assignment.
What is a Company ID (CID)?
A CID, like the OUI, is a unique 24-bit identifier. A CID though, cannot be used to generate universally unique MAC addresses. Therefore, the CID is especially applicable in applications where unique MAC addresses are not required. A CID should be applicable in most other cases where an OUI is specified. The CID has been created to reduce the consumption of OUI values. A CID assignment may not be used for Bluetooth or other similar applications.
For more information, please see the tutorial “Guidelines for Use of Organizationally Unique Identifiers (OUI) and Company ID (CID).”
Who can apply for a Standard Group MAC Address Assignment?
The Standard Group MAC Address assignment is for Standards Developers, or a Standards Development group, working to develop a new Standard. This assignment is not for companies that require MAC addresses for their products.
What is an Organizationally Unique Identifier (OUI)?
An OUI is a 24-bit globally unique assigned number referenced by various standards. (An OUI is assigned with a MA-L identifier block.) It can be used to identify an organization/company where a globally unique identifier is needed. The OUI is usually concatenated with other bits that are assigned by that organization in order to make a globally unique EUI-48 or EUI-64. EUI-48 and EUI-64 may be used as universally unique MAC addresses as used in the family of IEEE 802® standards. For example, the Ethernet MAC Address is an EUI-48, unique to one particular Ethernet interface. There are other uses of the OUI however, such as its use as a company identifier in the SNAP protocol.
For more information please refer to the OUI tutorial(Back to top)
Is it permissible to use the value of zero (00-00-00) as a placeholder for an OUI to be assigned later?
No. While waiting to obtain the value, a placeholder of nn-nn-nn or similar may be used. If there is already an OUI value associated with the standard, it should be used. If no such value is available then an OUI value should be obtained from the Registration Authority.
What is a "company_id"?
Until January 1 2014, the term "company_id" and OUI were considered equivalent to some, but the term company_id has been deprecated in favor of OUI for years. Beginning on January 1, 2014, Company ID (CID) was established as a unique registry. Either an OUI or CID may be used as a globally-unique 24-bit identifier of an organization, company, entity, manufacturer, vendor, etc.
What is an Individual Address Block (IAB)?
The Individual Address Block is an inactive registry activity, which has been replaced by the MA-S registry product as of January 1,2014. The owner of an already assigned IAB may continue to use the assignment until its exhaustion. The IAB was used by organizations/companies that required less than 4097 unique 48-bit numbers (EUI-48) and thus found it hard to justify buying their own OUI. The IAB uses a MA-L (and OUI) belonging to the IEEE Registration Authority, concatenated with 12 additional IEEE-provided bits (for a total of 36 bits), leaving only 12 bits for the IAB owner to assign to their (up to 4096) individual devices. Unlike an OUI, which allows the assignee to assign values in various different number spaces (for example, EUI-48, EUI-64, and the various CDI number spaces), the Individual Address Block could only be used to assign EUI-48 identifiers. All other potential uses based on the OUI from which the IABs are allocated are reserved, and remain the property of the IEEE Registration Authority. It should also be noted that, between 2007 and September 2012, the OUI value 00:50:C2 was used for IAB assignments. After September 2012, the value 40:D8:55 was used. Applications making use of EUI-48 values assigned under an IAB should have made no assumptions about the bit pattern present in the (24-bit most-significant) OUI portion of the assigned numbers.
What is a 36-bit Organizationally Unique Identifier(OUI-36)?
The OUI-36 is a deprecated registry activity name, which has been replaced by the MA-S registry product name as of January 1, 2014. This registry activity includes both a 36-bit unique number used in some standards and the assignment of a block of EUI-48 and EUI-64 identifiers by the IEEE Registration Authority. The owner of an already assigned OUI-36 registry product may continue to use the assignment.
Currently, the OUI-36 only refers to a 36-bit unique number used in some standards The OUI-36 of the MA-S assignment may be appended with 12 organization-supplied bits to form an EUI-48, or with 28 organization-supplied bits to form an EUI-64 (the identifier blocks assigned with an MA-S). .Applications making use of an MA-S should make no assumptions about the bit pattern that is present in the (24-bit most-significant) OUI portion of the assigned OUI-36.(Back to top)
What standards are involved with EUI-48, EUI-64, OUI and CID assignments?
Listing all the standards using these identifiers would be very difficult, and new uses continue to emerge; but a general listing includes:
- IEEE Std 802® provides general descriptions on use of EUI-48 and EUI-64 for universally unique MAC addresses, and use in protocol identifiers. The various IEEE 802.1™ standards provide specifications for bridging among networks using EUI-48 identifiers as MAC addresses.
- The various active IEEE 802 network types (Ethernet, Wireless Local Area Networks, Wireless Personal Area Networks, Broadband Wireless Access, and Wireless Regional Area networks)include greater detail on use of EUI-48 or EUI-64 MAC addresses for those protocols.
- Many emerging network types including IEEE 1901 Broadband over Power Line use addressing according to IEEE Std 802®.
- Uses of OUIs (or the historical term "company_id") are included in many IEEE, IETF, ITU, ISO, IEC and national standards. These standards either specifically call out use of the OUI as a 24-bit company identifier, manufacturer identifier or similar term; or define such a field and point to the IEEE RA as the source for such identifiers. It is intended that either a CID or OUI can be used in these fields. Many of these standards will be revised to also include reference to CID for these uses.
- Many standards define other extensions of the OUI for unique identifiers. These identifiers are referred to as context dependent identifiers. In these context dependent identifiers, the OUI/CID are concatenated with other fields defined in the standard (e.g., to identify a design model/version, to identify software entities, to identify company specific protocols, to identify company specific management attributes, etc.)
What is an Ethertype?
The Length/Type Field of an Ethernet/802.3™ data frame provides a context for interpretation of the Information Field that follows (i.e., protocol identification). Some values of this field are used to specify a length, the remainders are Ethertype values. Ethertypes are also used with other network types and may be found encapsulated within other protocols. Refer to IEEE Std 802.3, clause 3 and especially sub-clauses 3.1.1 and 3.2.6 for use of Ethertypes in a Length/Type Field. See also IEEE Std 802™ for a more general specification of usage.
I’m developing a new protocol; can I get an Ethertype assignment?
You do not need an Ethertype assignment to do protocol development. Because the number of Ethertype values is limited, and not all protocol developments are successful, two Ethertype values have been reserved for protocol development. These are formally called Local Experimental Ethertypes, though they are also known as Playpen Ethertypes. Use of Local Experimental Ethertypes is specified in IEEE Std 802a (upon revision of IEEE Std 802-2001, IEEE Std 802a will be merged into the new revision).
What are the criteria for an Ethertype assignment?
The requested new Ethertype must be sufficiently well defined (e.g., a protocol defined in a standard must have progressed sufficiently for ballot). The use of the Ethertype must also be properly defined to minimize exhaustion of available Ethertypes by the use of subtypes. Subtyping provides a path for enhancement without the need for the assignment of a further Ethertype in the future. Early use of Local Experimental Ethertypes (Playpen Ethertypes) helps protocol developers meet the requirements for proper design.
What is an Ethertype subtype?
Subtyping most often refers to the format described in IEEE Std 802a. Here, subtyping is defined for the two specific Local Experimental Ethertypes. The same format for subtyping is encouraged for simplicity, though not required to meet the subtyping criteria for getting an Ethertype assignment.
What is a Vendor Specific Protocol?
Vendor Specific Protocols are protocols that an organization or company has developed for broad deployment. These protocols may use the OUI Extended Ethertype rather than applying for a unique Ethertype value. The OUI Extended Ethertype is described in IEEE Std 802a. Though not currently specified in IEEE Std 802a, it is expected that either an OUI or CID can be used with the specified two-octet extension to create a globally unique protocol identifier.
What is IEEE Std 1451.4™-2004, what are its uses and how does it work?
IEEE Std 1451.4 is a member of the IEEE 1451™ family of smart transducer standards. Distinguishing features of IEEE 1451.4 are:
- A mixed-mode communication interface (MMI), which allows digital data and analog waveforms to alternately occupy a single connection, with analog bandwidth not limited by sampling. Also defined are separate data and analog connections for transducer applications not adapted to the shared connection.
- A transducer electronic data sheet (TEDS) definition, adapted to very small memories through the use of templates and containing identification and calibration data.
- A template description language (TDL) allowing ongoing development of templates for diverse transducer types.
- A rich template collection adapting 1451.4 to large family of transducers.
- A transducer block definition allowing 1451.4 to adapt to the 1451.1™ Object Model.
IEEE Std 1451.4 allows self-identification of transducers via the internal TEDS, easing bookkeeping in large measurement arrays. Stored sensitivity data allows data acquisition systems to standardize automatically to the installed transducers and track the transducers. A user field may be used to identify the transducer location in human readable format. The mixed-mode interface allows the analog waveform to be utilized in pristine form, without limitations of bandwidth introduced by sampling.
See a detailed description on IEEE Std 1451.4 operation.(Back to top)
What are the benefits of using IEEE Std 1451.4-2004?
The IEEE 1451 family provides a set of common interfaces between sensors or actuators, instruments and networks. With these standard interfaces, interoperability and interchangeability of sensors or actuators across different transducer networks are thus established. These standards reduce the effort needed to develop networked smart transducers. The use of IEEE 1451.4 based transducers offers the potential for simple plug and play operation, simplifying transducer installation and system upgrade. For transducer (sensor or actuator) manufacturers, the need for major redesign of their product for compatibility with a specific instrument or network is eliminated. They can deliver products for multiple instruments and networks based on one set of standard interfaces.
For control network vendors, the availability of a large pool of network-compatible sensors and actuators will likely increase the utilization of control networks, thus creating a push-pull effort.
For system integrators, the standard interfaces will provide a significant reduction in implementation effort.
For end users, IEEE Standard 1451.4-2004 has the potential to significantly reduce the total life-cycle costs of the sensor system or network, which include installation, maintenance, and upgrade.(Back to top)
What is an IEEE 1451.4 manufacturer_ID?
Within a 64-bit section of the 1451.4 TEDS, called basic TEDS, the manufacturer of the transducer is defined with a 14-bit code called the manufacturer ID, along with manufacturer-assigned transducer model number, model letter, model version number and serial number. (See IEEE Std 1451.4.2004 subclause 5.1.1, Table 2) The IEEE Registration Authority issues the manufacturer ID, to guarantee that it is unique to a manufacturer, and publishes the list of existing IEEE 1451.4 manufacturer ID's. Data acquisition systems may make use of the basic TEDS, including manufacturer ID, and model number data in determining the transducer type and the proper template to be used in unpacking TEDS data, particularly in the case of a transducer manufacturer choosing to use a non-IEEE, or manufacturer, template. Do not confuse manufacturer ID and basic TEDS with URN, as they are two separate and distinct entities.
More details on the 1451.4 manufacturer ID and Basic TEDS.
View the IEEE listing of 1451.4 manufacturer ID codes.
Apply for an IEEE 1451.4 manufacturer ID code.(Back to top)
What is a URN and why is it needed?
The unique registration number is a 64-bit unique identifier contained in the memory devices, or nodes, in which IEEE 1451.4 TEDS data is stored. Because multiple nodes may be arrayed in a multi-drop network format, to allow memory capacity to be increased, or other functions to be added, the URN allows a number of nodes to be individually accessed by the system. (See IEEE Std 1451.4.2004 sub clause 5.4, figure 2) See more details on the use of the URN in node devices. Do not confuse the URN with manufacturer ID and basic TEDS, as they are two separate and distinct entities.
IEEE 1451.4 transducer manufacturers using commercially available nodes obtain a URN automatically in each node they purchase. Manufacturers wishing to emulate the IEEE 1451.4 node function with an ASIC or micro-controller, for example, must purchase a URN for each node function produced, for this purpose, the IEEE Registration Authority issues blocks of 4096 URN codes. If you are producing nodes for use with IEEE 1451.4, and wish to purchase a block of URN codes from IEEE-RA fill out our application.(Back to top)
What is a transducer electronic data sheet (TEDS)?
Each of the standards in the IEEE 1451 family defines a storage format for data pertinent to a transducer, to be stored in the transducer. This data is called the transducer electronic data sheet, or TEDS. In general, transducer identification and calibration data are contained in the TEDS. In the case of IEEE 1451.4, the memory is large enough to contain only packed numerical data, without any units, which account for substantial memory usage in the TEDS definitions of the other standards. A template therefore defines the significance of the stored data in a 1451.4 transducer. The template is resident in the system, which reads the TEDS and unpacks the data.
View additional details on IEEE TEDS and templates(Back to top)
What is a template?
A template is a documented definition of the placement and significance of each piece of data stored within the TEDS memory. (see IEEE Std 1451.4-2004 sub clause 5.3) The template is not contained within the TEDS data, but the TEDS data identifies which template is to be referenced in interpreting the TEDS data. Templates must be accessible to the program code, which is used to write and read the TEDS data, allowing that data to be properly packed for writing and unpacked subsequent to reading. Templates are written in the template description language (TDL) and contained in template description files. The template description file is an ASCII text file, written in TDL, and having a file name extension of .tdl. (see IEEE Std 1451.4-2004 sub clause 6.1) IEEE Standard 1451.4-2004 annex A contains several examples of the template description file. Typically the template description file is read by an application program which, at the same time, reads and interprets (or generates and writes) the bits from (to) TEDS.
Who writes templates, where may they be obtained and how may I publish one?
Templates, or more precisely template description files, may be written by those having a transducer application not adapted to an IEEE published template. It is advisable that the library of IEEE templates be exhaustively investigated prior to undertaking writing a custom template, since it contains templates adapted to most transducer types. Using a standard template will save considerable effort by the user. The IEEE template description files can be found here.
Should writing a custom template be found necessary, please read and understand Clause 7, Template Description Language, contained in IEEE Std 1451.4-2004. Templates must be written in this language and the rules of the standard followed. More details on using TDL.
As described in the standard, a company or user can create templates for use by all to whom the template description files are distributed. A template description file may be submitted to IEEE for consideration as IEEE template by the manufacturer who developed the template of significant use, under the following condition:
- The submitted template must have been in use for a sufficiently long period and by a sufficient number of users to demonstrate its effectiveness and freedom from defects.
All new templates must conform to the TDL syntax rules and pass the syntax check program located in the TDL programmer's start-up kit described below.
Submit a new template to the IEEE-RA for consideration.
The application form and the template description file must be sent to the IEEE as indicated at the end of the form, for listing as an IEEE template. Manufacturers may elect to use non-IEEE templates for their own 1451.4 compliant products. Manufacturers choosing to use unpublished, manufacturer templates are solely responsible for the distribution and effective usage of these templates. All manufacturer templates must conform to the TDL syntax and template format guide. The format guide and TDL syntax check program are located in the TDL start-up kit.
NOTICE: The attached software is currently undergoing BETA testing. The software has not been verified for any particular purpose. USE AT YOUR OWN RISK. The software is intended solely as a tool of convenience. The software does NOT guarantee that a given product is or will be compliant with IEEE-SA Standards and is NOT intended to be used, explicitly or implicitly, to certify or assure such compliance, and you shall NOT represent or imply to others that IEEE-SA has tested, certified or otherwise approved of any product developed through use of this software.
Download (.zip) the programmer's start-up kit for writing templates.(Back to top)
What is the template description language?
A major driving force behind the development of the IEEE 1451.4 standard was the need to minimize the amount of memory required to store a TEDS; with a stated objective of only needing 256 bits, although more are allowed. This requires a method of mapping the bits in a precise fashion. This bit mapping is accomplished through templates which are text based files written in the template description language (TDL). The TDL is a formal language similar to programming languages, but with considerably less looping and conditional control. This is because the entire purpose of the language is to map bits and not to implement general processing or mathematical capabilities.
Additional details on the functionality and syntax of the TDL.(Back to top)
How can I obtain an assignment of a URN Block(s)?
The IEEE Registration Authority issues IEEE 1451.4 URNs on a fee basis, in blocks of 4,096 numbers. Apply for IEEE 1451.4 URN blocks. Note: There is a maximum of 10 assignments that can be issued at one time.
What are the costs involved in obtaining a manufacturer ID or URN block assignment, or in publishing a new template? What is the method of payment?
The IEEE Registration Authority oversees the issuance of IEEE 1451.4 manufacturer ID numbers and URN blocks and keeps a current listing of the IEEE 1451.4 template files. To cover administrative costs, fees are charged for manufacturer ID numbers and URN blocks and to publish new templates. Payment terms are listed with the fees for each of these services.
Determine the fee or to obtain a manufacturer ID number.
Determine the fee or to obtain a URN block.
Determine the fee or to publish a new template.(Back to top)
How may I obtain the names and ID numbers of those companies who own a manufacturer ID or URN block assignment?
The listings of existing IEEE 1451.4 manufacturer ID numbers and URN blocks are available for no charge, from the IEEE Registration Authority.
View existing manufacturer ID numbers.
There are no URN blocks assigned by the IEEE Registration Authority at this time.(Back to top)
May I re-sell or distribute a segment of the URN block after I obtain it?
The IEEE Registration Authority distributes URNs in blocks of 4,096, which is considered to be the smallest practical volume for administration purposes, at a reasonable fee for small volume users. IEEE-RA does not sanction the re-sale of partial URN blocks, due to the danger of loss of uniqueness. Several divisions within a company may share a block of URNs, however.
My company wants an additional manufacturer ID number for our new project. Can we receive one?
Manufacturers may obtain an additional manufacturer ID number only when the original has become exhausted. A statement must be furnished to the IEEE Registration Authority, verifying that 95% of the capacity of the original number has been used. The manufacturer ID occupies 14 bits of a 64-bit transducer identifier called the basic TEDS. The pool of individual transducer model numbers available to each holder of a single manufacturer ID, using the remaining 50 bits of the Basic TEDS as defined in IEEE Standard 1451.4-2004, is therefore in excess of 54.5 million model numbers. Each model may be produced up to a total in excess of 16.7 million serialized copies. By changing the version number or version letter, as defined in the Standard, a larger total of serialized copies of a given model may be supported. The total number of individual units identifiable using the IEEE Standard 1451.4-2004 basic TEDS, under a single manufacturer ID, is slightly in excess of 9 x 1014.
What is a PSID?
PSID stands for Provider Service Identifier. It is a globally unique integer value that is associated with a service being provided using a communications system such as 5.9 GHz DSRC WAVE.
Who maintains PSID allocations?
The allocation of PSIDs is maintained and administered by the IEEE Registration Authority (IEEE-RA).
What is the PSID used for?
The PSID has three uses in the WAVE system.
A PSID is used to identify the next higher layer (for example an application, service, protocol, entity, etc.) so that WAVE Short Messages (WSMs) are routed to where they are needed.
A PSID is used to identify services that are available on a WAVE network, allowing consumers of those services to consume them.
A PSID is used to identify the permissions of the sender of some information.(Back to top)
Do I need a new PSID to be allocated to my service?
If you or your organization are planning to develop an ITS service, then you might need a PSID.
If your service will utilize the WAVE Short Message protocol, then that service will need to be associated with a PSID. If your service utilizes IPv6 as the networking protocol, then you do not necessarily need a PSID to be allocated.
If your service will be advertised via the WAVE Service Advertisement mechanism, then your service will need a PSID.
If your service will utilize 1609.2 certificates then you will need a PSID allocated to your service.
Many PSIDs have already been allocated. If your service is based on an existing specification that uses an already allocated PSID, then you may be able to utilize that PSID.(Back to top)
Where can I find a list of already allocated PSIDs?
The PSID registry is maintained and administered by the IEEE Registration Authority. You may view the list of allocated PSIDs by visiting the IEEE-RA website. The list of allocated PSIDs known at time of publication can be found in IEEE Std 1609.12-2016.
What are testing PSIDs?
Testing PSIDs have been pre-allocated for use in research and development projects. These can be used by any organization in development of their application.
You do not need to request to use a PSID allocated to testing, just start using it. For the list of allocated testing PSIDs, see IEEE Std 1609.12-2016.(Back to top)
What size PSID should I request?
In the WAVE standards, a PSID is encoded into an octet string which can be from one to four octets in length. The number of octets requested depends on a number of factors which should be considered by the requester.
One and two octet PSIDs have limited availability and will be allocated on a limited basis. If your application is safety critical, and is expected to generate a large number of over-the-air messages, then your application may qualify for one of these PSIDs.
Four octet PSIDs will be suitable for most applications. If you request a PSID with fewer than four octets, then you must justify the need. The final determination regarding the PSID size that is allocated will be made by the IEEE-RA.(Back to top)
What is p-encoding?
When PSIDs are formatted into over-the-air messages in a WAVE system, they are converted to a compact encoding known as p-encoding. See IEEE Std 1609.12-2016 for details, and for a way to convert between the integer form and the p-encoded form.
How many PSIDs can I request at one time?
In most cases you must complete a separate PSID request form for each PSID you are requesting.
Can I request a specific PSID value?
No. If your allocation request is approved, the IEEE-RA will inform you of the value or values allocated.
What is the process for requesting a PSID?
If you have determined that you need to request a PSID allocation, take the following steps:
- Complete and submit the PSID Request Form found on the IEEE-RA website here.
- You will be notified by IEEE-RA of the result of your request. This may take 90 days or more. This is a new process, and the IEEE-RA strives to respond in a timely manner.
- You can appeal the decision if you don’t agree with it
- If you have questions regarding the process, see the IEEE-RA website for additional details and contact information.
What is expected of the assignee of a PSID?
At some point in the development cycle of an application or service that is intended to be deployed, it is expected that a corresponding specification will be developed to facilitate interoperability. The assignee has the authority to specify the Provider Service Context (PSC) and the Service Specific Permissions (SSP) associated with the PSID.
If your application is using 1609.2 certificates it will be necessary to identify a certificate authority that will issue certificates with your PSID. Certification of an implementation developed to a specification may be required in order to receive certificates.
A specification may be public or private.(Back to top)
How can I learn more about PSIDs and DSRC WAVE based systems?
For detailed information and specifications related to 5.9 DSRC WAVE systems, please see IEEE Std 1609.0-2013, IEEE Std 1609.2-2016, IEEE Std 1609.3-2016, IEEE Std 1609.4-2016 and IEEE Std 1609.12-2016. See also the WAVE and PSID Tutorial found here.
What is an Operator ID (OpID)?
An OpID is a 24-bit number that, per IEEE Std 802.16, is broadcast by each base station as part of its Base Station ID. An 802.16 network consists of one or more base stations operating as a coordinated system, with each base station in the coordinated network broadcasting the same OpID. The IEEE Registration Authority assigns the IEEE 802.16 Operator ID to be used as the Operator ID. See the Operator ID tutorial.
Is an IEEE-assigned Operator ID required in order to deploy an IEEE 802.16 network?
No. Typical commercial systems providing public service require a globally unique OpID. This can be obtained from the IEEE Registration Authority. Alternately, a globally unique OpID can be derived from an operator's E.212 MCC-MNC assignment. For networks providing service to a limited group of users where a globally unique OpID is not required by the operator, the OpID may be selected from the Public OpID pool. In this deployment scenario, the OpID may be selected from the pool to avoid having different networks in the same geographical area using the same OpID or so that a single operator can operate base stations with a single public OpID.
Can I use another assignment as an IEEE 802.16 Operator ID, or vice versa?
No. These are separate identifiers. They must be obtained separately and are not interchangeable.
What is a Base Station ID?
The Base Station ID is a 48-bit number defined by IEEE Std 802.16 to be broadcast by each base station. The OpID defines the most significant 24-bits of the Base Station ID. An 802.16 network consists of one or more base stations operating as a coordinated system, with each base station in the coordinated network broadcasting the same OpID. By programming unique values in the least significant 24-bits of the Base Station ID for each base station, the Base Station ID then uniquely identifies each and every base station in the coordinated 802.16 network.
How can I obtain the names and ID numbers of those companies who own an IEEE 802.16 Operator ID?
The latest available version of the OpID assignments can be found on the IEEE Registration Authority website.
Can I re-sell the IEEE 802.16 Operator ID after I obtain it?
No. If a company is sold, the OpID may be transferred to the new company. However, the OpID cannot be sold by anyone other than IEEE Registration Authority. See above.
How can I obtain an assignment of an IEEE 802.16™ Operator ID?
Check the public listing to determine whether your company already has an assignment. If not, then complete the OpID application.
Once the application is completed successfully, the Applicant will receive an e-mail with a tracking number and payment information. The application will be processed within seven days after receipt of payment as long as there are no problems with the information on the application or the payment. The Applicant will receive an e-mail with the assignment information once the application is processed.(Back to top)
My company needs multiple IEEE 802.16 Operator ID s for multiple networks. Can we receive them?
Yes. The IEEE Registration Authority will accept an application for an allocation of up to 100 OpIDs. If additional OpIDs are needed, you may complete an additional application. However, users of 802.16 OpIDs are encouraged to make most efficient use of this limited numbering resource. In typical deployment scenarios, the network operator will need only a single OpID, keeping in mind that a single OpID will support over 16 million Base Station IDs.
My regulator requires that I use my E.212 MCC-MNC to identify my network. How can I do this with IEEE Std 802.16 and OpID?
The MCC + MNC combination is a valid, globally unique 802.16 OpID. Specific coding of the MCC + MNC is required in order to be used in an 802.16 network. Coding instructions are included in the Operator ID tutorial.
If my organization already has an E.212 MCC-MNC allocation, are we compelled to use it as the Operator ID with our 802.16 network? Are we disallowed from applying for an 802.16-specific OpID from the IEEE Registration Authority?
No. The formula for conversion of an E.212 MCC-MNC pair to an 802.16 OpID is only provided for those organizations that wish to use their E.212 network ID with 802.16, or may be required by regulation to do so. Organizations should check with their regulatory authorities as to whether they are required to use their current E.212 MCC-MNC pair to identify their networks using 802.16 standards. Any organization may obtain 802.16-specific OpID(s) from the IEEE Registration Authority, subject to the general terms & conditions covering application.
Are there geographic restrictions on the use of an OpID?
The OpID is assigned for worldwide use.
Are all of the OpIDs globally unique?
An OpID allocated by the IEEE Registration Authority is assigned to a single applicant. The assignee is guaranteed that the same number is not assigned to any other entity. Furthermore, the set of OpIDs that are assigned is disjoint from the set of OpIDs that may be derived from an E.212 MCC-MNC. The IEEE Registration Authority does not guarantee the MCC-MNC pair is unique. However, if all operators respect the rules for generating OpIDs and make use of unique MCC-MNC pairs, the OpID will be unique, since an OpID cannot be derived from two different E.212 MCC-MNC assignments. Any OpID selected from the Public OpID Pool is not guaranteed to be unique, as two operators may coincidently choose the same OpID. An operator choosing an OpID from the Public Pool must assess the consequences of another operator choosing the same OpID. For operators of a home or small enterprise network, the consequences may be insignificant, and choosing an operator ID from the public pool is a viable option.
If we do not apply for our own OpID to program into our base stations, will they all have the same "default" operator ID?
The 802.16 standard requires the use of the OpID, as allocated by the IEEE Registration Authority. Failure to populate the a BS with an appropriate OpID will result in non-standard deployment and non-standard results. The value of the OpID field in new equipment is manufacturer-specific and should be verified by the operator.
When may I make use of the Public OpID Pool?
A network OpID may be selected from the Public OpID Pool . Although such an OpID is not guaranteed to be globally unique, it will not cause mis-operation of any 802.16 SS/MS within its coverage or interference zones. Base stations in networks offering public service must use a globally unique OpID. Operators of base stations or networks using the Public OpID Pool should utilize appropriate access security techniques.
What is the probability of duplication of a private network ID?
Although the total range of values is large, calculations of the probability of duplication in making a selection of truly random values from the full range yield the following results:
- Within 10 random selections, there is a probability of duplication of 0.18%
- With 23 random selections, there is a probability of duplication of 1%.
- There is a 10% probability of duplication within a selection of 72 numbers;
- There is a 50% probability of duplication within a selection of 185 numbers;
- There is a 99% probability of duplication within a selection of 476 numbers.
From this it may be concluded that there is, for example, a 10% chance that mis-operation due to OpID duplication may occur if there are 72 (otherwise identical) base stations closely located such that their associated MSs may see signals from all the other BSs.
This article is about a type of network address. For the Apple computers, see Macintosh. For other similar terms, see Mac.
A media access control address (MAC address) of a device is a unique identifier assigned to network interface controllers for communications at the data link layer of a network segment. MAC addresses are used as a network address for most IEEE 802 network technologies, including Ethernet and Wi-Fi. In this context, MAC addresses are used in the medium access control protocol sublayer.
MAC addresses are most often assigned by the manufacturer of a network interface controller (NIC) and are stored in its hardware, such as the card's read-only memory or some other firmware mechanism. If assigned by the manufacturer, a MAC address usually encodes the manufacturer's registered identification number and may be referred to as the burned-in address (BIA). It may also be known as an Ethernet hardware address (EHA), hardware address or physical address (not to be confused with a memory physical address). This can be contrasted to a programmed address, where the host device issues commands to the NIC to use an arbitrary address.
A network node may have multiple NICs and each NIC must have a unique MAC address. Sophisticated network equipment such as a multilayer switch or router may require one or more permanently assigned MAC addresses.
MAC addresses are formed according to the rules of one of three numbering name spaces managed by the Institute of Electrical and Electronics Engineers (IEEE): MAC-48, EUI-48, and EUI-64. The IEEE claims trademarks on the names EUI-48 and EUI-64, in which EUI is an abbreviation for Extended Unique Identifier.
The original IEEE 802 MAC address comes from the original Xerox Ethernet addressing scheme. This 48-bit address space contains potentially 248 or 281,474,976,710,656 possible MAC addresses.
The distinction between EUI-48 and MAC-48 identifiers is purely nominal: MAC-48 is used for network hardware; EUI-48 is used to identify other devices and software. (Thus, by definition, an EUI-48 is not in fact a "MAC address", although it is syntactically indistinguishable from one and assigned from the same numbering space.)
The IEEE now considers the label MAC-48 to be an obsolete term, previously used to refer to a specific type of EUI-48 identifier used to address hardware interfaces within existing 802-based networking applications, and thus not to be used in the future. Instead, the proprietary term EUI-48 should be used for this purpose.
In addition, the EUI-64 numbering system encompasses both MAC-48 and EUI-48 identifiers by a simple translation mechanism. To convert a MAC-48 into an EUI-64, copy the OUI, append the two octets and then copy the organization-specified extension identifier. To convert an EUI-48 into an EUI-64, the same process is used, but the sequence inserted is . In both cases, the process can be trivially reversed when necessary. Organizations issuing EUI-64s are cautioned against issuing identifiers that could be confused with these forms. The IEEE has a target lifetime of 100 years for applications using MAC-48 space, but encourages adoption of EUI-64s instead.
IPv6 — one of the most prominent standards that uses a Modified EUI-64 — treats MAC-48 as EUI-48 instead (as it is chosen from the same address pool) and toggles the U/L bit (as this makes it easier to type locally assigned IPv6 addresses based on the Modified EUI-64). This results in extending MAC addresses (such as IEEE 802 MAC address) to Modified EUI-64 using only (and never ) and with the U/L bit inverted.
An Individual Address Block (IAB) was a 24-bit OUI managed by the IEEE Registration Authority, followed by 12 IEEE-provided bits (identifying the organization), and 12 bits for the owner to assign to individual devices. An IAB is ideal for organizations requiring not more than 4096 unique 48-bit numbers (EUI-48). IABs have been replaced with 12-bit "MA-S" address blocks.
Universal vs. local
Addresses can either be universally administered addresses (UAA) or locally administered addresses (LAA). A universally administered address is uniquely assigned to a device by its manufacturer. The first three octets (in transmission order) identify the organization that issued the identifier and are known as the organizationally unique identifier (OUI). The remainder of the address (three octets for MAC-48 and EUI-48 or five for EUI-64) are assigned by that organization in nearly any manner they please, subject to the constraint of uniqueness. A locally administered address is assigned to a device by a network administrator, overriding the burned-in address.
Universally administered and locally administered addresses are distinguished by setting the second-least-significant bit of the first octet of the address. This bit is also referred to as the U/L bit, short for Universal/Local, which identifies how the address is administered. If the bit is 0, the address is universally administered. If it is 1, the address is locally administered. In the example address 06-00-00-00-00-00 the first octet is 06 (hex), the binary form of which is 00000110, where the second-least-significant bit is 1. Therefore, it is a locally administered address. Another example that uses locally administered addresses is the DECnet protocol. The MAC address of the Ethernet interface is changed by the DECnet software to be AA-00-04-00-xx-yy where xx-yy reflects the DECnet network address xx.yy of the host. This eliminates the need for an address resolution protocol since the MAC address for any DECnet host can be simply determined.
Unicast vs. multicast
If the least significant bit of the first octet of an address is set to 0 (zero), the frame is meant to reach only one receiving NIC. This type of transmission is called unicast. A unicast frame is transmitted to all nodes within the collision domain. In a modern wired setting the collision domain usually is the length of the Ethernet cable between two network cards. In a wireless setting, the collision domain is as far as the radio transmitter can reach. A switch will forward a unicast frame through all of its ports (except for the port that originated the frame), an action known as unicast flood, if the switch has no knowledge of which port leads to that MAC address. Only the node with the matching hardware MAC address will accept the frame; network frames with non-matching MAC-addresses are ignored, unless the device is in promiscuous mode.
If the least significant bit of the first octet is set to 1, the frame will still be sent only once; however, NICs will choose to accept it based on criteria other than the matching of a MAC address: for example, based on a configurable list of accepted multicast MAC addresses. This is called multicast addressing.
The IEEE has built in several special address types to allow more than one network interface card to be addressed at one time:
- Packets sent to the broadcast address, all one bits, are received by all stations on a local area network. In hexadecimal the broadcast address would be . A broadcast frame is flooded and is forwarded to and accepted by all other nodes.
- Packets sent to a multicast address are received by all stations on a LAN that have been configured to receive packets sent to that address.
- Functional addresses identify one or more Token Ring NICs that provide a particular service, defined in IEEE 802.5.
These are all examples of group addresses, as opposed to individual addresses; the least significant bit of the first octet of a MAC address distinguishes individual addresses from group addresses. That bit is set to 0 in individual addresses and set to 1 in group addresses. Group addresses, like individual addresses, can be universally administered or locally administered.
The following network technologies use the MAC-48 identifier format:
Every device that connects to an IEEE 802 network (such as Ethernet and WiFi) has a MAC-48 address. Common networked consumer devices such as PCs, smartphones and tablet computers use MAC-48 addresses.
EUI-64 identifiers are used in:
- IEEE 1394 (FireWire)
- IPv6 (Modified EUI-64 as the least-significant 64 bits of a unicast network address or link-local address when stateless autoconfiguration is used)
- ZigBee / 802.15.4 / 6LoWPAN wireless personal-area networks
Usage in hosts
On broadcast networks, such as Ethernet, the MAC address is expected to uniquely identify each node on that segment and allows frames to be marked for specific hosts. It thus forms the basis of most of the link layer (OSI Layer 2) networking upon which upper layer protocols rely to produce complex, functioning networks.
Although intended to be a permanent and globally unique identification, it is possible to change the MAC address on most modern hardware. Changing MAC addresses is necessary in network virtualization. It can also be used in the process of exploiting security vulnerabilities. This is called MAC spoofing.
In IP networks, the MAC address of an interface can be queried given the IP address using the Address Resolution Protocol (ARP) for Internet Protocol Version 4 (IPv4) or the Neighbor Discovery Protocol (NDP) for IPv6. In this way, ARP or NDP is used to relate IP addresses (OSI layer 3) to Ethernet MAC addresses (OSI layer 2).
According to Edward Snowden, the US National Security Agency has a system that tracks the movements of everyone in a city by monitoring the MAC addresses of their electronic devices. As a result of users being trackable by their devices' MAC addresses, Apple has started using random MAC addresses in their iOS line of devices while scanning for networks. If random MAC addresses are not used, researchers have confirmed that it is possible to link a real identity to a particular wireless MAC address.
Many network interfaces (including wireless ones) support changing their MAC address. The configuration is specific to the operating system. On most Unix-like systems, the ifconfig command may be used to add and remove "link" (Ethernet MAC family) address aliases. For instance, the "active" ifconfig directive may then be used on NetBSD to specify which of the attached addresses to activate. Hence, various configuration scripts and utilities allow to randomize the MAC address at boot or network connection time.
Using wireless access points in SSID-hidden mode (see network cloaking), a mobile wireless device may not only disclose its own MAC address when traveling, but even the MAC addresses associated to SSIDs the device has already connected to, if they are configured to send these as part of probe request packets. Alternative modes to prevent this include configuring access points to be either in beacon-broadcasting mode, or probe-response with SSID mode. In these modes, probe requests may be unnecessary, or sent in broadcast mode without disclosing the identity of previously-known networks.
The standard (IEEE 802) format for printing MAC-48 addresses in human-friendly form is six groups of two hexadecimal digits, separated by hyphens () in transmission order (e.g. ). This form is also commonly used for EUI-64 (e.g. ). Other conventions include six groups of two hexadecimal digits separated by colons () (e.g. ), and three groups of four hexadecimal digits separated by dots () (e.g. ); again in transmission order.
The standard notation, also called canonical format, for MAC addresses is written in transmission bit order with the least significant bit transmitted first, as seen in the output of the ifconfig, iproute2, and ipconfig commands, for example.
However, since IEEE 802.3 (Ethernet) and IEEE 802.4 (Token Bus) send the bytes (octets) over the wire, left-to-right, with least significant bit in each byte first, while IEEE 802.5 (Token Ring) and IEEE 802.6 send the bytes over the wire with the most significant bit first, confusion may arise when an address in the latter scenario is represented with bits reversed from the canonical representation. For example, an address in canonical form would be transmitted over the wire as bits in the standard transmission order (least significant bit first). But for Token Ring networks, it would be transmitted as bits in most-significant-bit first order. The latter might be incorrectly displayed as . This is referred to as bit-reversed order, non-canonical form, MSB format, IBM format, or Token Ring format, as explained in RFC 2469.
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