Palo Alto, Calif. This is where the big boys would like to be. Officials from some well-known internetworking firms have created a company ready to tackle the tough problem of building high-performance IP networks that avoid the bottlenecks of traditional routers. At Ipsilon Networks, Inc.s coming-out party last week, the company took the wraps off an switching platform that combines the intelligence of IP routing with the speed of Asynchronous Transfer Mode switching. Ipsilon's IP Switch ATM 1600 is intended to break through the physical logjam of switched internets that couple routers and switches. It also sidesteps the political impasse that has stifled the efforts of standards groups to meld routing and ATM (NW, Feb. 19, page 6). 'There's no focus, no stability in the ATM Forum,' said Tom Lyon, Ipsilon's founder, chairman and chief technical officer. Lyon is a 12-year veteran of Sun Microsystems, Inc. and the creator of the ATM Adaptation Layer 5 specification for converting data units to ATM cells. Ipsilon's management team also includes President and Chief Executive Officer Brian NeSmith, who founded Newbridge Networks, Inc.'s VIVID group; Larry Blair, vice president of marketing, who, as cofounder of Kalpana, Inc., is regarded as the father of Ethernet switching; and officials from Cisco Systems, Inc., Novell, Inc., Network Equipment Technologies, Inc., Advanced Computer Communications and BBN. Due to a legacy in shared-media connectivity and slow standards development, the largest internetworking vendors - such as Bay Networks, Inc., Cabletron Systems, Inc. and Cisco - are still talking about the promises of IP routing and ATM switching in grandiose 'marketectures' such as CiscoFusion, but they are not delivering product, analysts said. And while most vendors focus on end-to-end ATM, Ipsilon is aiming to bring ATM performance to IP nets. The IP Switch ATM 1600 implements the IP protocol stack on ATM hardware and dynamically determines when to switch and when to route based on the needs of IP conversations, or flows. For longer flows, such as HyperText Transfer Protocol, File Transfer Protocol, telnet and multimedia applications, IP Switch ATM 1600 performs cut-through switching in the ATM hardware. For shorter conversations, it uses store-and-forward IP routing. Switch/route methods cobbled together by vendors today usually require users to implement a flat net that is limited in scalability or a hierarchical structure rife with router-hop bottlenecks, users said. 'Each router hop examines the packet, which slows down the performance of sending them along,' said Noemi Berry, network development engineer at the National Aeronautics and Space Administration's Ames Research Center in Mountain View, Calif. 'But the trouble with switched networks is that they operate at Layer 2 and you lose the scalability, robustness and hierarchical addressing of IP. Now in comes Ipsilon saying you don't have to commit yourself to Layer 3 or Layer 2.' Instead, users commit to using Ipsilon's software, and Ipsilon hardware or other vendors' switching and routing hardware. Ipsilon's software provides call setup, teardown and call status, and flow redirection messages between switches and hosts. The IP Switch ATM 1600 hardware platform includes an Intel Corp. PCI bus and sports a Pentium Pro processor and a Multimedia Communications, Inc. ATM chipset. In addition, it features 16 155M bit/sec ports, 2.3G bit/sec of nonblocking bandwidth and routing performance of more than five million IP packets per second. Ipsilon also rolled out the IP Switch Gateway, which connects existing Ethernet, fast Ethernet and FDDI LANs to the IP Switch ATM 1600. Ipsilon's challenge is to have its technology adopted by the leading internetworking vendors, according to Fred McClimans, principal of Decisys, Inc. in Sterling, Va. The IP Switch ATM 1600 costs $46,000. It will ship in April. &Ipsilon: (415) 846-4600.