Creating Advanced Functions on Network Processors : experience and Perspectives

Abstract

In this paper, we present five case studies of advanced networking functions that detail how a network processor (NP) can provide high performance and also the necessary flexibility compared with Application-Specific Integrated Circuits (ASICs). We first review the basic NP system architectures, and describe the IBM PowerNP architecture from a data-plane as well as from a control-plane point of view. We introduce models for the programmer's views of NPs that facilitate a global understanding of NP software programming. Then, for each case study, we present results from prototypes as well as general considerations that apply to a wider range of system architectures. Specifically, we investigate the suitability of NPs for * Quality of Service (active queue management and traffic engineering), * header processing (GPRS tunneling protocol), * intelligent forwarding (load balancing without flow disruption), * payload processing (code interpretation and just-in-time compilation in active networks), and * protocol stack termination (SCTP). Finally, we summarize the key features as revealed by each case study, and conclude with remarks on the future of NPs.