netx Snapshot
  • Small-footprint (small as 5KB, automatic scaling)
  • Fast execution (achieve wire speed, no packet copying)
  • Supports all popular processors and tools (see below)
  • Phase-II IPv6 Ready Logo Certification
  • TraceX system analysis support
  • BSD-compatible socket layer
  • Advanced Features:
    • UDP Fast-Path Technology(TM)
    • Flexible pachet management
    • Additional protocols: AutoIP, DHCP, DNS, FTP, HTTP, NAT, POP3, PPP, SMTP, SNMP v1-2-3, SNTP, Telnet, TFTP
  • Full Source Code
  • Royalty-Free
NetX Architecture Support
  • ARM
    • ARM7, ARM9, ARM11
    • Cortex-M, Cortex-R, Cortex-A
    • Cortex-Axx 64-bit
  • AndesCore
  • Analog Devices
    • Blackfin BF5xx, BF6xx, BF7xx
    • SHARC
  • Cadence
    • Xtensa
    • Diamond
  • CEVA
    • TeakLite-III
  • EnSilica
    • eSi-RISC
  • NXP
    • ARM (LPC, i.MX, Kinetis)
    • 68K
    • Coldfire
    • PowerPC
  • Imagination
    • MIPS32 4Kx, 24Kx, 34Kx, 1004K
    • microAptiv, interAptiv, proAptiv
    • M-Class
  • Intel
    • ARM (Cyclone)
    • NIOSII
    • x86PM
  • Microchip
    • ARM (SAM)
    • AVR32
    • PIC24
    • PIC32
  • Renesas
    • ARM (Synergy, RZ)
    • H8/300H
    • RX
    • SH
    • V850
  • Silicon Labs
    • EMF32
  • ST
    • STM32
  • Synopsis
    • ARC 600, 700
    • ARC EM, ARC HS
  • Texas Instruments
    • ARM (Tiva-C, Sitara, OMAP
    • C5xx
    • C6xx
  • Xilinx
    • ARM (Zynq)
    • MicroBlaze
    • PowerPC



NetX™ and NetX Duo™ TCP/IP Protocol Stacks

NetX and NetX Duo are Express Logic’s high-performance implementations of TCP/IP protocol standards. NetX provides a streamlined, IPv4 capable TCP/IP stack, while NetX Duo is Express Logic’s new TCP/IP stack that provides both IPv4 and IPv6 capabilities in a dual-stack product. Both NetX and NetX Duo are fully integrated with ThreadX and are available for all supported processors. NetX and NetX Duo have a unique Piconet™ architecture. Combined with a zero-copy API, they are a perfect fit for today’s deeply embedded applications that require network connectivity.

NetX Duo Features

NetX Duo conforms to RFC standards and offers complete interoperability with devices from other vendors. NetX Duo offers several new capabilities. For the first time, nodes can configure their interface addresses automatically through the Stateless Address Autoconfiguration protocol. Nodes also can use layered structures to enable devices more efficiently to process IPv6 headers. NetX Duo implements the following protocols:

  • All IPv4 features available in NetX 5.x
  • IPv6 header and extension header processing
  • Neighbor Discovery Protocol
  • Router Discovery Protocol
  • Stateless Address Autoconfiguration
  • Duplicate Address Detection
  • Phase-II IPv6 Ready Logo Certification


    NetX Duo has achieved IPv6-Ready Logo certification, evidence that it has passed conformance and interoperability tests, administered and validated by the IPv6 Forum. There are two phases of testing, Phase-I and Phase-II. Phase-I is relatively basic and limited to verification of select IPv6 capabilities. Phase-II is much more rigorous and extensive, and is a superset of Phase-I.

    Express Logic chose to seek Phase-II approval, which required NetX Duo to pass an extremely challenging set of 373 test cases, which cover the following RFCs:

  • RFC 2460 - IPv6 Specification
  • RFC 4861 - Neighbor Discovery for IPv6
  • RFC 4862 - IPv6 Stateless Address Autoconfiguration
  • RFC 1981 - Path MTU Discovery for IPv6
  • RFC 4443 - ICMPv6
  • These test cases make sure the implementation conforms to core IPv6 operations.

    The Phase-II Interoperability tests ensure that the implementation is able to work with other devices and routers. This test requires setting up a test network with multiple routers and hosts, and to validate that NetX Duo follows the IPv6 standard and correctly interacts with other hosts and routers.

    NetX Duo has successfully performed these tests and has received official IPv6-Ready Logo certification, enabling Express Logic to join a select, small group of embedded software companies who can proudly display the IPv6 Ready logo, indicating that they have completed this rigorous testing and validation process.

    Protocol Components

    NetX and NetX Duo provide a complete set of protocol components that comprise the TCP/IP standard, including the following:

  • Full TCP/IP Networking
  • IPv4 and IPv6 Support
  • Flexible Packet Management
  • Internet Protocol (IP)
  • Address Resolution Protocol (ARP)
  • Reverse Address Resolution Protocol (RARP)
  • Internet Control Message Protocol (ICMP)
  • Internet Group Management Protocol (IGMP)
  • User Datagram Protocol (UDP)
  • Transmission Control Protocol (TCP)
  • NetX Applications

    Application Layer protocols, including AutoIP, DHCP, DNS, mDNS, DNS-SD, FTP, HTTP, NAT, POP3, PPP, SMTP, SNMP, SNTP, Telnet, TFTP, and a BSD-compatible socket layer, also are available from Express Logic for NetX. In addition, our partners offer several related higher-level solutions, including SSL/SSH/TLC, UPnP/DLNA, and Application Servers, all fully integrated with NetX and NetX Duo.

    NetX Duo Applications

    Aditional components, including HTTPv6, FTPv6, DNSv6, Telnetv6, and DHCPv6 (client only) are available for NetX Duo, and more are coming soon.


    NetX Duo (optionally) incorporates IPsec (Internet Protocol Security), a protocol suite for securing Internet Protocol (IP) communications by authenticating and encrypting each IP packet of a communication session. IPsec also includes protocols for establishing mutual authentication between agents at the beginning of the session and negotiation of cryptographic keys to be used during the session. IPsec protects any application traffic across an IP network. Applications do not need to be specifically designed to use IPsec.

    Small Footprint

    NetX and NetX Duo are implemented as a C library. Only the features used by the application are brought into the final image. The minimal footprint of NetX is as small as 5KB on CISC processors.

    Piconet™ Architecture

    Many TCP/IP implementations have a considerable number of function calls sprinkled throughout the packet processing path. Although this is fine for workstation software, it is not acceptable for performance critical embedded applications. The elimination of layered function calls and loosely coupled protocol components is what we call a piconet architecture.

    Zero-Copy API

    NetX and NetX Duo provide zero-copy TCP/IP communication to eliminate processor cycles consumed by moving data to and from user buffers. This results in very high performance and frees processor cycles back to the application for useful activities.

    BSD Sockets Interface

    In addition to the zero-copy, highly-optimized NetX API, NetX also provides a BSD sockets compatible API for applications with legacy BSD application code.

    Flexible Packet Pool Management

    The application may create any number of packet pools in any number of memory areas . These zero-copy packets can be linked with packets from the same pool or even a different pool to accommodate larger payloads.

    UDP Fast Path™ Technology

    Basic UDP packets pass through NetX and NetX Duo without any copying and without any system context switches. Many commercial network stacks process all packets received within a system thread thereby adding a context switch to the packet overhead. In NetXand NetX Duo, simple UDP packets are delivered directly to waiting threads.

    Fast Response

    With its non-layering Piconet™ architecture and zero-copy API, NetX and NetX Duo's packet processing speeds are exceptionally fast.

    Easy To Use

    NetX and NetX Duo are very easy to use. The NetX and NetX Duo API is both intuitive and highly functional. NetX Duo also recognizes and processes NetX API calls for full compatibility. API names are made of real words and not the “alphabet soup” names that are common to other TCP/IP products. Building a NetX or NetX Duo application is easy. Simply include the header file in the application software and link the application objects with the NetX or NetX Duo library. The resulting image is ready for execution – it’s that simple!

    No Mysteries

    NetX and NetX Duo are delivered with complete C source code so you can see exactly how they operate. If you are used to in-house TCP/IP stacks or had bad experiences with “black box” commercial products, this should be most comforting.

    Express Logic Gets You to Market First

    Express Logic products are designed for ease-of-use. Everything from well thought out APIs to simple startup procedures help you get up and running in a matter of hours! This coupled with advanced debugger integration, make our products the easy choice to win the race to market!

    Partner Solutions


  • Allegro Embedded SSL Solutions: Allegro SSL
  • RTL SharkSSL: Real-Time Logic SharkSSL
  • Cypherbridge uSSL: Cypherbridge uSSL
  • UPnP

  • Allegro Media Server: Allegro Media Server
  • Application Server

  • RTL Barracuda Application Server: Real-Time Logic Barracuda Application Server
  • Allegro's RomPager Intro™

    Allegro’s RomPager Intro is an entry-level embedded Hyper Text Transfer Protocol (HTTP) Web server ideal for getting familiar with the concepts of device connectivity, management and remote configuration. RomPager Intro serves objects to browsers or other Web clients, handles the HTTP protocol, passes URL requests to a user application, and sends formatted responses to the a requesting browser or HTTP client. Fully compliant with HTTP 1.0/1.1 specifications, RomPager Intro offers superior performance and can handle thousands of concurrent requests. The RomPager® suite of products is proven technology currently deployed in 75+ million units worldwide. For those with more sophisticated networking requirements, Allegro offers a full line of embedded networking software development toolkits to support advanced embedded networking such as: Network Security (SSH, SSL/TLS, DTLS, RADIUS), Connected Consumer Media devices (UPnP/DLNA toolkits, DTCP-IP, WMDRM), Machine-to-Machine communications (HTTP Client, XML, SOAP) and Device Management (Advanced HTTP servers, CLI, Telnet). All of these products utilize the same flexible interfaces employed by RomPager Intro when running with ThreadX and NetX. Full programming and interface details for RomPager Intro are described in the RomPager Intro Programming Reference Guide.pdf.

    RomPager Intro is available free of charge for NetX licensees. Contact Express Logic for details.