Sun and Fujitsu are to merge their Sparc-based server product lines by 2006, expanding a long-standing partnership between the two companies.

The new combined product line, code named APL, or Advanced Product Line, "will replace Sun's and Fujitsu's existing Sun Fire and PrimePower product lines", the companies said in a statement. "We're going to be bringing a whole series of low and mid-range and high-end products to the market," Sun chief Scott McNealy said.

Sun and Fujitsu have collaborated for years on the design of the UltraSparc chip architecture used in both companies' servers. Today's news is an "expansion and acceleration" of a 20-year strategic relationship between the companies, McNealy said.

The deal with Fujitsu will allow Sun to focus on its next generation of "throughput computing" chip designs while taking advantage of Fujitsu's own processor development efforts at the same time.

The APL systems will be based on Fujitsu's upcoming Sparc64 VI processor, and the complete line of servers will be manufactured by both Sun and Fujitsu, with Fujitsu doing the manufacturing in certain geographic regions and Sun doing this in others. The two companies will maintain their separate sales forces, marketing groups and product brands, McNealy said.

Sun will continue to develop the multi-core throughput computing processors - codenamed Niagara and Rock - that it has been working on since its 2002 acquisition of Afara WebSystems and will manufacture systems based on these chips. Fujitsu will have the option of selling systems based on the throughput processors, McNealy said.

Sun recently transferred the bulk of its UltraSparc V development team to its throughput computing efforts, raising questions about the role throughput processors would play in its future product plans. With this announcement, Sun now has an additional processor, Fujitsu's Sparc64, on which it can build future servers.

Sun's current line of UltraSparc III and UltraSparc IV systems "will have continued enhancements that will continue to drive those chips between now and 2006," McNealy said.

"The deal makes so much sense that it was almost surprising that it hadn't happened yet," said Gordon Haff, an analyst with Illuminata. "Sun's increased x86 focus may be a good business decision in its own right but only raises more questions about how it could profitably continue SPARC development. And Fujitsu has issues of its own, especially in selling in North America. The two companies are very complementary in both technologies and markets," he said.

Sun's first Niagara systems are expected to begin shipping in 2007. Systems based on its Rock architecture will follow in 2007, Sun said.