Likely, especially if the technology is a big success, WiMAX standards will never be completely finalized. Other standards such as the cable DOCSIS have continued to evolve, even once a very mature level of performance was realized. However, it has evolved more slowly. WiMAX being a young standard has moved swiftly through several updates even before testing standards were defined and products began to be widely available. Its final Fixed WiMAX version standard is close to market. Firms are already involved in product testing. In fact, four firms, Redline, Aperto, SEQUANS and Wavesat have already achieved Fixed WiMAX Certification on the air interface portion of Fixed WiMAX. A further 25 plus companies are scheduled to undergo testing in the second round, which will certify not only the air interface, but QOS and other optional elements. These optional elements will serve as differentiators for vendors to separate themselves from their competitors.

The technology has evolved from the base 802.16 standard through several updates during the last few years including:

802.16a

802.16c

And finally 802.16d or 802.16-2004

All of which are primarily Fixed WiMAX standards. The most recent standard of 802.16-2004 has been completely finalized.  As stated above, interoperability testing is well underway with the first phase of air interface testing already certifying four companies. More than 25 more firms are slotted to be tested in the second phase.

Another version called 802.16e or Mobile WiMAX was finalized late in 2005. This version is not backwards compatible with the 802.16-2004 fixed standard   

Products based on this standard are being worked on assiduously by vendors who believe that meeting the mandatory elements will leave their final products very close to certifiable status. This should jump start product availability (at least with some early gear) in late 2006 and early 2007. Interoperability testing for Fixed WiMAX products is well into the second phase (The QOS phase) and companies are very rapidly ramping up to complete interoperability testing for Mobile WiMAX products.

A newer iteration of WiMAX called 802.16m that defines mesh radio aspects of WiMAX is in the works. This standard should handily support the exploding Municipal Mesh Network industry, which has become a heavy driver of broadband wireless in both the US and abroad.