2001-06-06 IEEE 802.16l-01/14 IEEE 802.16 Working Group on Broadband Wireless Access http://WirelessMAN.org Dr. Roger B Marks NIST 325 Broadway, MC 813.00 Boulder, CO 80303 USA Tel: +1 303 497 3037 Fax: +1 303 497 7828 mailto:marks@nist.gov 6 June 2001 Dr.-Ing.Jamshid Khun-Jush, Chair, ETSI BRAN mailto:Jamshid.Khun-Jush@eed.ericsson.se Dear Jamshid: On behalf of IEEE 802.16, I thank you for your letter dated 5 April, delivered on 16 May, and denoted IEEE 802.16l-01/13. We were very pleased to learn that your HIPERMAN group had reviewed our submission carefully and are happy to respond with more information. In particular, we would like to answer your question: “What is the IEEE 802.16 definition of interoperability?” While the Working Group maintains no formal definition of the term, we would generally defer to The IEEE Standard Dictionary of Electrical and Electronics Terms (IEEE Standard 100-1996). The appropriate definition therein is this one: The capability, promoted but not guaranteed by joint conformance with a given set of standards, that enables heterogeneous equipment, generally built by various vendors, to work together in a network environment.” In particular, I note that, in IEEE 802.16l- 01/09, we responded positively to assessment of IEEE 802.16 drafts with respect your criterion that “The standard, to be developed by ETSI Project BRAN, MUST support interoperability.” In the case of IEEE 802.16, our policy is to define multiple physical layers (PHYs) operating under a unified MAC layer. These PHY options address a number of different frequencies, with the intent to support many different regulatory domains throughout the world. Each of the PHY options is intended to support an interoperable air interface. While a mixture of PHY modes might not be interoperable with each other, the choice of any single mode is intended to result in full interoperability. I should note that we continue to consolidate our options where possible. For instance, at our Session #13 of 14-18 May, we moved to reduce the number of PHY modes in our 10-66 GHz draft from two to one. For more details on this session, please see our report <http://ieee802.org/16/meetings/mtg13/report.html>. Regarding our informal discussion of adding an 802.16/HIPERACCESS clause to Annex 1 of the Co-operation Agreement between ETSI and IEEE-SA, 802.16 would like to try and formalize our cooperation. I propose the clause below, with the understanding that you need to update the BRAN Terms of Reference. We believe that progress in this area will aid our cooperation, though we could go ahead with certain actions (such as IEEE copyright release for ETSI use of the 802.16 draft) beforehand.