Throughout the book, we have not only discussed the most important components that comprise a network-processing platform, but we have also looked at the specific offerings of most important vendors in the field. We have examined network processors versus net application-specific integrated circuits (Net ASICs) versus configurable, multiprocessor-based custom designed ASICs. We have also discussed embedded or separate traffic managers, switch fabrics, search engines, content-addressable memories (CAMs), classification processors, and storage network processors. Security coprocessors are discussed in Chapter 17, Security Coprocessors.

However, some issues cannot be easily categorized into one single area of the field as they span the entire problem space that designers of a multiservice router (MSR) confront. In this chapter, we attempt to combine the most important of these issues to wrap up the information provided throughout the book. We need to examine the soundness of the architectural choices made by the most important vendors to get a clear idea of the result of using approach A as opposed to approach B.

However, architecture is not the only issue. Software must also be developed. This often involves cost-related issues, which we will try to elucidate especially for newcomers into this field. Some experienced users may be surprised by our discussion as we will try to debunk some industry-wide myths. When making decisions, a designer must consider both visible and hidden costs.

For the sake of convenience, we will also clarify various memory subsystem technologies that may...