Unique Registration Number

Unique Registration Number

The URN is a 64-bit unique identifier contained in the memory devices, or nodes, in which IEEE 1451.4 Transducer Electronic Data Sheets (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. It utilized to ensure unique access to IEEE 1451.4 TEDS memory devices arranged in a multi-drop two conductor network as described in IEEE Std 1451.4-2004. (see IEEE Std 1451.4.2004 subclause 5.4, figure 2)

The URN is the basis upon which node-addressable, digital communication takes place, within the multi-drop architecture of the IEEE 1451.4 mixed-mode interface. It contains an 8-bit family code (FD) to identify the functions available in the node and the command set to be used with the node. Each node must contain a 64-bit URN to control access to the TEDS.

Organizations wishing to design devices emulating the operation of commercially available nodes, with an ASIC or micro-controller for example, for use in 1451.4 systems, must obtain URN codes for installation, one per device. The system reads the URN least-significant bit first.

The IEEE Registration Authority will assign blocks of 4,096 individual URN’s to any organization, from the IEEE pool of 68.7 billion blocks. IEEE will assign up to 10 blocks per purchase.

Users purchasing commercially available node devices for use in their products do not need additional URN codes, since a URN is contained in each purchased device.

Do not confuse the URN with manufacturer ID and basic TEDS, as they are two separate and distinct entities.

Registration Fees

Product Fees
URN Block Assignment US $1,730
There may be intellectual property issues associated with the use of URNs that requesters are responsible to ascertain and satisfy. They may require the purchase of a license(s) and to pay a royalty to third parties who claim ownership to the intellectual property. It is strongly recommended that before purchasing an URN to review the IEEE SA patent listing to obtain information relevant to that URN. IEEE does not accept requests for applicant-specified identifiers.

Application Information

  1. Complete and submit the URN Application (PDF). Applications expire after 30 days.
  2. Any questions regarding your application will be sent via email to the REQUESTOR.
  3. Applications are processed within 30 business days from receipt of payment. Assignment details and a Paid Invoice are sent to the REQUESTOR.
  4. The public URN listing is updated once every 24 hours, so new assignments will not be immediately viewable in the directory.

Related Standards

  • IEEE 1451.4
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