SpaceWire Products and Services

4Links designs and manufactures a comprehensive range of SpaceWire test equipment. All of our test products are capable of achieving class-leading performance and of providing an unequalled insight into the operation of your SpaceWire network.

All 4Links test products make testing SpaceWire easy for you, whatever the computer and operating system you use, wherever you are in the world, and wherever the system you are testing might be. They interface to your computer via Gigabit Ethernet and use the standard TCP/IP protocols so that they can be accessed remotely (for instance by partners collaborating on a mission). Because Ethernet and TCP/IP are universally supported, our products do not require special device drivers, so they can be controlled by software running on almost any operating system. Software, including programming APIs and example programs, is supplied with full source code.

Our units have a robust power connector that takes DC power (both 24(28)V nominal Aerospace and 48V nominal Telecommunications standards) and they are supplied with a universal AC adaptor. Test and simulation equipment must protect flight equipment from possible damage caused by the test environment. Our RG408 platform protects flight equipment with five layers of current and voltage protection.

The 4Links Diagnostic SpaceWire Interface

All of our rack-mounted products have a large, clear front-panel display that provides useful operational information independently from any external software.

Particular recent products include the Multi-link SpaceWire Recorder, which provides passive recording of packets on your network, and the SpaceWire Remote Memory Access Protocol (RMAP) Responder, which has the performance to emulate your RMAP target hardware at equivalent speeds. A key aspect of these, and of the enhanced Diagnostic SpaceWire Interface, is that they allow you to synchronize high-resolution time-tags across an entire SpaceWire test system. Furthermore, these time-tags may be synchronized to an external IRIG time source using our Absolute Time Interface, to produce records suitable for archiving.

4Links continuously improves and extends its range of test equipment. In many cases, customers who already own a 4Links EtherSpaceLink family product may be able to field-upgrade to these new products or capabilities simply by plugging in a new memory card that contains extra firmware modules. Hardware upgrades are also available, where required, but customers must return their hardware platform to 4Links for a short period in this case.

Our full product line-up includes:

SpaceWire Interfaces and Bridges
EtherSpaceLink ESL-RG201 The 4Links ESL-RG201 is our entry-level single-port Ethernet to SpaceWire bridge.
EtherSpaceLink ESL-RG401/8 The ESL-RG401/8 is our high performance SpaceWire bridge between Gigabit Ethernet and one of eight SpaceWire ports.
Diagnostic SpaceWire Interface (DSI) The 4Links Diagnostic SpaceWire Interface (DSI) is a high-performance Ethernet to SpaceWire bridge, connecting up to eight simultaneously active SpaceWire ports. It also provides comprehensive diagnostics of the activity on all of these ports.
SpaceWire Monitors
Multi-link SpaceWire Analyzer (MSA) The 4Links Multi-link SpaceWire Analyzer (MSA) monitors up to four SpaceWire links, reporting statistics of all the low-level SpaceWire characters (both data and control) transmitted in each direction on each link. It constantly monitors for errors and the software provided displays waveforms of the wire signals before and after an error.
Multi-link SpaceWire Recorder (MSR) The 4Links Multi-link SpaceWire Recorder (MSR) monitors SpaceWire packets in both directions on up to four links per MSR unit, adding time-tags for the start and end of each packet. It then sends this information via Ethernet to a computer, for recording and analysis.
SpaceWire Simulators
Flexible SpaceWire Router (FSR) The Flexible SpaceWire Router from 4Links is an eight-port SpaceWire routing switch that provides Ethernet connectivity for its control, monitoring and diagnostics.
SpaceWire RMAP Responder (SRR) The 4Links RMAP Responder is a SpaceWire Remote Memory Access Protocol (RMAP) Data Store with up to six SpaceWire ports and an Ethernet Interface
SpaceWire Network Infrastructure Devices
Absolute Time Interface (ATI) Our Absolute Time Interface (ATI) synchronises a SpaceWire network to an IRIG time source, so that archived test records can be time-tagged to sub-microsecond accuracy.
Flexible SpaceWire Router (FSR) The Flexible SpaceWire Router from 4Links is an eight-port SpaceWire routing switch that provides Ethernet connectivity for its control, monitoring and diagnostics.
SpaceWire Laboratory Cables Our low-cost SpaceWire cables for the test laboratory are flexible, available in standard and custom lengths, and you may choose between two styles of connector termination.
Specifying and Upgrading our Products
Product Options This page lists the options available for the 4Links range of SpaceWire test equipment. Additional options for a product are supplied on replacement firmware memory cards.
Firmware and Hardware Platform Details It is possible to convert most of our RG40x platform products into others in the same range, to provide additional functionality without the need to purchase more hardware. Most of these upgrades involve new firmware that can be provided on a memory card for installation by the customer, provided that the existing hardware is sufficiently capable.

4Links products are distributed in North America by Cobham Semiconductor Solutions (Aeroflex), and 4Links is represented in Japan by Prominent Network. Prospective customers from elsewhere in the world should contact our UK headquarters by email at, or by telephone at +44 1908 642001.

Find a full list of our Product Brief documents here.

A summary of the 4Links company background and our SpaceWire products is available in our Product Brochure