VIRAGE LOGIC ADDS BINARY CAM TO ITS NETCAM FAMILY OF EMBEDDED CONTENT.

As network hardware designers are squeezing more functionality into less space, while simultaneously striving to improve performance, Virage Logic has developed a high-performing CAM that allows them to optimize critical design factors such as speed, power and area. The Custom-Touch NetCAM product family embodies embedded memories that generate both high-speed ternary and binary CAMs that can be embedded into IC designs for use in network applications such as routers and switches.

CAMs are today's essential components in hardware-based search engines, which are key enablers in moving traffic through a network. As the explosive growth of the Internet continues to put a tremendous amount of pressure on the network, routers and switches need to examine packets of information and make forwarding decisions every few nanoseconds. With a 16K Virage Logic binary CAM, network hardware designers will experience a speed improvement of about 33 percent over the corresponding ternary CAM due to the binary CAM's smaller area. The 16K binary CAM, which runs at 218 MHz worst case is about 40 percent smaller in area and consumes 50 percent less power as compared to a ternary CAM of the same size. The NetCAM B-128K is capable of generating binary CAMs that are 128 Kbits in size. This represents a four-fold increase in the maximum size of CAMs as compared to the earlier ternary CAM (NetCAM T-32K) product from Virage Logic.

"The continuing evolution of the Internet depends, in large part, on the ability of semiconductor intellectual property (SIP) companies such as Virage Logic to provide innovative solutions to reduce or remove system bottlenecks altogether," said Fred Berkowitz, vice president of engineering at AMCC's Switching and Network Processing Group. "With Virage Logic's NetCAM compiler, we can efficiently embed CAMs, enabling us to provide the higher speed and quality of service required to move traffic through the Internet."

The binary CAM, NetCAM B-128K, joins the ternary CAM, NetCAM T-32K, to complete the family of NetCAM embedded memories. The difference between the binary and ternary CAM is that the binary CAM stores data as 0's and 1's, whereas the ternary CAM stores data as -0's, 1's and "don't cares." Because the binary CAM does not have to store "don't cares," it is smaller and can utilize the silicon area much more efficiently. It also performs much more coarsely grained searches than ternary CAMs. When a system designer is trying to determine how many binary and ternary CAMs to embed on-chip, the decision is typically based on how often the searches need to be fine-grained (ternary CAM) vs. course-grained (binary CAM). In order to achieve high silicon utilization, it is usual to embed a few ternary CAMs and mostly binary CAMs on-chip.

By cascading binary CAMs, the designer can increase the bandwidth of the CAMs, and allow for searches on very wide words. This is key for high-bandwidth applications that need to facilitate the search process. Because binary CAMs have an integrated address encoder, they are much easier to cascade than ternary CAMs.

"Both binary and ternary CAMs have emerged as the search engines of choice in a number of applications including network routers and switches, Virtual Private Networks (VPNs) and firewalls because of their ability to conduct high-speed table lookups that are required to meet the ever-growing traffic on the Internet," said Krishna Balachandran, director of product marketing at Virage Logic. "With the addition of our new binary NetCAM B-128K embedded memory IP, we can now offer a full array of CAMs in 0.18 micron technology to meet the demands of our networking customers and including those implementing design architectures for graphics, speech, security, and image recognition systems. We have taken the leadership position by offering the only commercially available embedded CAM compilers producible in TSMC and UMC processes."