product brief
Intel IXP425 Network
Processor Family
Optimized for Broadband Applications
Product Highlights
Internet Exchange
Intel® XScale™ RISC core up to 533 MHz
Three network processor engines
Two high-speed serial interfaces
Two 10/100 Base-T Ethernet MACs with
MII/RMII interface
UTOPIA 2 interface—multiple
ADSL/G.SHDSL or VDSL support
PCI version 2.2 Host and Option interface
Hardware Security Accelerator (IPsec:
USB version 1.1 device controller
Two UARTS—one High-Speed UART
(921.6 Kbaud) and one Console UART
(230.4 Kbaud)
32-bit wide SDRAM controller
Sixteen GPIO pins
16-bit configurable expansion bus
ATM, TDM, Ethernet MAC filtering, and
HDLC support
Operating system support for VxWorks*
and Linux*
Commercial and Extended temperature
Product Overview
To meet the growing demand from homes and
businesses for high-performance broadband
access services, manufacturers must develop
new networking products that are capable of
provisioning rich services. The Intel® IXP425
network processors are designed to meet the
needs of last-mile applications, such as customer premises equipment, and mini-DSLAMs
for multi-dwelling units (MxUs). These network
processors deliver wire-speed performance and
sufficient "processor headroom" for manufacturers to add a variety of rich software services to
support their networking applications. These
are highly integrated network processors that
support multiple WAN and LAN technologies
giving customers a common architecture for
multiple applications.
With their Development Platform, a choice
of operating systems, and a broad range of
development tools, the Intel IXP425 network
processors provide a complete development
environment for faster time-to-market. This
network processor family offers the choice of
multiple clock speeds at 266, 400, and 533
MHz, with both Commercial (0° to 70° C) and
Extended (-40° to 85° C) temperature options.
Architected for Broadband Applications
The Intel IXP425 network processor family
meets the requirements of next-generation
broadband applications by integrating a unique
distributed processing architecture that
features the performance of the Intel XScale
core and three Network Processor Engines
(NPEs). The combination of the four highperformance processors provides tremendous
processing power and enables wire-speed
performance at both the LAN and WAN ports.
Distributed Processing Architecture
The Intel XScale core and the three NPEs run
their instruction streams in parallel. The Intel
XScale core is fully compatible with ARM* V5T
Thumb instructions set and V5E DSP extensions. Designed on the Intel® 0.18-micron
process technology, the Intel XScale core
delivers the industry-leading MIPs to power
consumption ratio and provides ample processing headroom for the customer to add
differentiating product features.
Distributed Processing Architecture (continued)
The three NPEs are designed to offload many computationally intensive data plane operations from the Intel
XScale core. These tasks include: IP header inspection
and modification; packet filtering; packet error checking;
check sum computation; flag insertion and removal; PDU
segmentation and assembly; and encryption. The NPE
architecture includes an ALU, self-contained internal data
memory, an extensive list of I/O interfaces, together with
hardware acceleration engines (also known as NPE
coprocessors). It is the NPE coprocessor associated
with an NPE that targets a set of networking applications.
Each NPE coprocessor is designed to accelerate a
specific networking task that would otherwise take many
MIPs to complete by a stand-alone RISC processor.
Each NPE can take care of Layer 2 and, in some cases,
Layer 3 packets that are passed through them. For example,
the WAN/Voice NPE has one UTOPIA 2 interface and two
high-speed serial interfaces so its internal processing is
targeting the handling of AAL (1/2/5) SARing, TDM framing,
and HDLC processing. An MII/RMII interface is attached
to both the Ethernet NPE A and the Ethernet NPE B
respectively. The Ethernet NPE A also has two internal
coprocessors to accelerate VPN related tasks such as
3DES and Hashing at speeds up to full-rate ADSL. The
Ethernet NPE B is capable of handling 100Mb/s, full-duplex
Ethernet packet filtering. The extensive hardware capabilities
of these NPEs are all under the management of a set of
NPE microcode drivers that are released as a software
library together with the Intel IXP425 network processors.
Customer applications configure and interact with the
NPEs through a high-performance API layer running on
the Intel XScale core.
Wire-Speed Performance
The Intel IXP425 network processors implement a fast
path design in the NPE software library to provide
optimized performance for broadband applications.
The fast path design passes non-inspection IP packets
directly from the ingress port NPE (usually WAN/Voice
NPE with the xDSL WAN port) to the egress port NPE
(usually Ethernet NPE A or B with the Ethernet LAN port)
without the involvement of the Intel XScale core. Since
the vast majority of IP packets move from the WAN to
the Ethernet LAN, isolating these data flows to the NPEs
within the Intel IXP425 network processor produces a
significant throughput improvement by eliminating the
need to route packets through a central processor. The
most demanding situation occurs when small (64 byte)
IP packets are sent at the speed that saturates the
physical layer (wire speed). For example, nearly 10,000
(64 byte) packets per second will be sent downstream
in an ADSL connection that runs at the maximum wire
speed (8 Mb/s downstream). The NPEs and fast path
design in the Intel IXP425 network processors are capable
of providing, at minimum packet sizes, wire-speed performance up to 52 Mb/s on the WAN side and 100 Mb/s on
the Ethernet LAN.
Highly-integrated Data, Voice, and
Security Functionality
On-chip integration of data, voice, and security functions
saves the cost of implementing separate devices and
supports easier integration with other hardware. Integrated
into the Intel XScale core are multiply and accumulate
functions that give customers the ability to do multimedia
processing without the need for external hardware. For
example, in a voice application, the Intel XScale core can
perform a wide variety of speech coding and telephony
algorithms without the need for an external DSP chip. In
addition, the network processors integrate two 10/100
Base-T Ethernet MACs with MII/RMII interface and simultaneous full-duplex operation. To further reduce the total
solution chip count, a SDRAM controller has been integrated along with peripheral functions that include interrupt
controller, GPIO port, UART, watchdog timer and generalpurpose timers. A USB version 1.1 device controller is
integrated for those applications that require USB support. The Intel IXP425 network processors also provide
hardware acceleration for security applications. These
chips implement, in hardware, DES and 3DES data
encryption algorithms as well as SHA-1 and MD5
hashing algorithms typically used in VPN applications.
A direct connection to DSP chips and flash memory is
achieved through the expansion bus interface. By
integrating more functionality, Intel is reducing the total
solution chip count and cost for broadband applications.
Broad Range of LAN and WAN Capabilities
The Intel IXP425 network processors offer a full range of
broadband and LAN access solutions through multiple
integrated interfaces. Through the UTOPIA 2 interface,
there is performance to support up to eight ADSL PHYs,
eight G.SHDSL PHYs or one VDSL PHY. The PCI version 2.2 Host and Option interface gives customers the
flexibility to directly connect such devices as 802.11x
chips, PCMCIA controllers, Ethernet MACs, and cable
MAC/PHYs. These network processors also feature
two high-speed serial interfaces. These interfaces can
serve as high-speed ports for direct connection to
T1/E1 framers or to industry-standard SLIC/CODECS.
Choice of Tools and Operating Systems Supports
Rapid Development
The Intel XScale microarchitecture offers a broad range
of tools together with support for two widely adopted
operating systems. The Intel IXP425 network processors
support VxWorks and the standard Linux 2.4 kernal.
MontaVista Software* will provide the support for Linux.
To help speed time-to-market and reduce development
costs, developers will have a wide choice of third-party
tools, including compilers, linkers, debuggers and
board support packages (BSPs). Tools include Wind
River* Tornado* 2.1.1 for the VxWorks 5.4 real-time
operating system, and the complete GNU* Linux
development suite.
Development Platform For Faster Time-to-Market
The Intel® IXDP425 Network Processor Development
Platform is a powerful tool for developing and verifying
hardware and software for the Intel IXP425 network
processors. Developers can use this flexible and extendable platform to conduct rapid initial chip evaluation,
chip performance evaluation, product development
and prototyping. For additional information, refer to the
Intel IXDP425 Development Platform product brief.
Four high-performance processors in a distributed
processing architecture
Wire-speed performance; Able to offer rich data,
voice and security services
Highly-integrated data/voice/security functions
Reduced chip count; Cost savings;
Simplified design
Broad range of WAN/LAN capabilities
Flexibility; Common architecture for multiple platforms
Development Platform
Faster time-to-market
Commercial and Extended temperature options
Intel® Internet Exchange Architecture
The Intel IXP425 network processors are part of Intel® Internet Exchange Architecture (Intel® IXA) which is a packet processing
architecture that provides a foundation for software portability across multiple generations of network processors and is
based on the Intel XScale microarchitecture. Additional information on Intel IXA is available on the Web site listed at the end
of this document.
Product Ordering Information
Order Number
Intel IXP425 Network Processor, 266 MHz
Intel® IXP425 Network Processor, 400 MHz
Intel® IXP425 Network Processor, 533 MHz
Intel IXP425 Network Processor, 266 MHz Extended Temperature
Intel® IXP425 Network Processor, 400 MHz Extended Temperature
Intel® IXP425 Network Processor, 533 MHz Extended Temperature
Intel IXDP425 Network Processor Development Platform
Intel® IXP425 Network Processor Family Literature
Order Number
Intel IXP425 Network Processor Family Product Brief
Intel IXDP425 Network Processor Development Platform Product Brief
Please contact your Intel Representative for the following documents:
Intel® IXP425 Network Processor Datasheet
Intel® IXP425 Network Processor Developer's Manual
Intel® IXP425 Network Processor Programmer's Guide
Intel Access
Developer‘s Site
Network Processor Web Site
Intel® Internet Exchange Architecture
Networking and Communications Building Blocks
Other Intel Support:
Intel Literature Center
(800) 548-4725 7 a.m. to 7 p.m. CST (U.S. and Canada)
International locations please contact your local sales office.
General Information Hotline
(800) 628-8686 or (916) 356-3104 5 a.m. to 5 p.m. PST
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