F). The double data rate (DDR) DRAM memory subsystem supports the nuts and bolts of the network processor's store-and-forward processing model. Table 5.1 provides a very raw comparison between the capabilities of the IXP1200 and the more recent IXP2400 and IXP2800. For a more detailed description and comparison, see the Intel product literature available from the company's networking products web site at www.intel.com/design/ network/ixa.htm. Intel incorporated several second-generation enhancements into the IXP2400 and IXP2800 net- work processors in order to handle packet-processing operations flexibly and powerfully. One of these TABLE 5.1 Comparison of the Major Characteristics between the Most Prominent Intel Network Processors FEATURE IXP1200 IXP2400 IXP2800 Speed realm of applicability OC-3 to OC-12 OC-48 OC-192 Number of microengines Instruction store for each microengine Giga-operations per second >25.2 Packet-processing performance in 14 million 60 million numbers of enqueue/dequeue packet operations per second Integrated memory controllers SRAM and DDR DRAM and 3 RDRAM and SDRAM 2QDR SRAM 4 32-bit QDR SRAM Processor core frequency 166 MHz with 400/600 MHz 700 MHz other family chips at 200 and 232 MHz Microengine operating frequency 166 MHz 400/600 MHz 1.4/1.0 GHz Peak bandwidth of I/O bus 6.26 Gbps Package 1356 Ball FCBGA 1356 Ball FCBGA Power consumption 3.8 watts at 166 MHz 10 watts at 600 MHz Standard interfaces beyond PCI 104 MHz IX bus 2 unidirectional 32-bit 2 unidirectional 16-bit media interfaces, which LVDS data interfaces can become SPI-3, programmable as SPI-4 Utopia 1/2/3, or CSIX-L1, Phase 2 or CSIX all at 25 to 125 MHz Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. INTEL IXA TM NETWORK PROCESSORS INTEL IXA TM NETWORK PROCESSORS enhancements is local memory (refer to Figure 5.3). Local memory is now available in each