Express Logic Rolls Out NetX Duo IPv4/IPv6 Dual Stack

Express Logic, Inc., the worldwide leader in royalty-free real-time operating systems (RTOS), announced the availability of NetX Duo(tm) its new dual IPv4/IPv6 TCP/IP stack. NetX Duo is built upon the solid field-proven foundation of Express Logic’s NetX TCP/IP stack, an IPv4-only solution. Now, as developers recognize the greatly expanded demands of Internet enabled devices, NetX has been extended to support IPv6 as well.

IPv6, the latest standard set by the Internet Engineering Task Force (IETF), expands and supplements the capabilities of IPv4, particularly in the number of available IP addresses. IPv4 uses a 32-bit field, resulting in just over 4 billion unique IP addresses. With the ever-growing use of global Internet devices and the uneven distribution of network addresses, certain large organizations and geographic regions are experiencing a shortage of unique IP addresses. IPv6 uses a 128-bit address field, which provides room for 3.4*(10^38) unique addresses, more than enough for every person to own thousands of addresses and for every device to connect directly to the Internet.

Because NetX Duo is an IPv4 and IPv6 dual TCP/IP stack, it can handle both IPv4 and IPv6 protocols as well as being highly optimized for performance-critical embedded devices. Its modular architecture allows designers to customize various components based on their system requirements. NetX Duo APIs are fully backward compatible with the IPv4 services in NetX. Therefore existing NetX applications can be migrated to NetX Duo with minimal porting effort.

“NetX Duo simplifies developers’ jobs by enabling them to transition from IPv4 to IPv6 seamlessly, as their customers demand,” commented William E. Lamie, president of Express Logic. “NetX Duo answers the need for expanded IP capabilities, with the ability to support legacy needs at the same time.”

NetX Duo has been tested for RFC compliance using the TAHI test suite (phase 2). This ensures that NetX Duo conforms to RFC standards and offers complete interoperability with devices from other vendors. NetX Duo implements the following protocols and RFCs:

  • 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
  • RFC2460: Internet Protocol, Version 6 (IPv6) Specification
  • RFC2461: Neighbor Discovery for IP Version 6
  • RFC2462: IPv6 Stateless Address Autoconfiguration
  • RFC2464: Transmission of IPv6 Packets over Ethernet Networks
  • RFC4291: Internet Protocol Version 6 (IPv6) Addressing Architecture
  • RFC4443: Internet Control Message Protocol (ICMPv6) for the Internet Protocol Version 6 (IPv6) Specification

Thanks to implementing the IPv6 protocol, NetX Duo also enjoys several new capabilities. For the first time, nodes can configure their interface addresses automatically through the Stateless Address Autoconfiguration protocol. As well, nodes can use layered structures to enable devices to more efficiently process IPv6 headers.

Shipping and Availability
NetX and NetX Duo(tm) are available immediately from Express Logic, with license prices starting at $12,500 for NetX and $18,750 for NetX Duo, with no run-time royalties.

About Express Logic
Headquartered in San Diego, CA, with field offices in Reddich, UK, and Hanover and Munich, Germany, Express Logic offers the most advanced run-time solution for deeply embedded applications, including the popular ThreadX® RTOS, the high-performance NetX(tm) TCP/IP stack, the FileX® embedded MS-DOS compatible file system, the USBX(tm) Host/Device USB protocol stack, and the TraceX(tm) real-time graphical event trace and analysis tool. All products from Express Logic include full source-code and have no run-time royalties. For more information about Express Logic solutions, please call 1-888-THREADX, or email inquires to

ThreadX and FileX are registered trademarks, and NetX, NetX Duo, CANX, USBX, TraceX, preemption-threshold, picokernel, UDP fast path technology, are trademarks of Express Logic, Inc.