ADFX or ARINC 664 is a protocol that is derived from the Ethernet protocol. What I understand it is

  • Point to Point (no routing of data)
  • Deterministic
  • used VLAN for addressing

I just wonder do we have to get specialised router that cater to ADFX? Can the conventional ethernet router/switch(for eg used in home, office) be used instead?


EDIT: Sorry based on answer below given, I would like to edit my question to being instead of routers to switch

  • $\begingroup$ This question would be better suited on serverfault $\endgroup$ – Manu H Aug 18 '20 at 8:03
  • 2
    $\begingroup$ @ManuH I'm not sure that it would, as ADFX or ARINC 664 is probably off-topic for serverfault. $\endgroup$ – selectstriker2 Aug 18 '20 at 13:37
  • $\begingroup$ @selectstriker2 serverfault is better suited for network protocols (this seems to be a question about physical layer (layer2) and network layer (layer3) of a specific network protocol) $\endgroup$ – Manu H Aug 18 '20 at 14:03
  • $\begingroup$ But it is specific (exclusive?) to aviation, not something typical in the commercial world. $\endgroup$ – selectstriker2 Aug 18 '20 at 14:08
  • $\begingroup$ @ManuH, ARINC 664 it is specific to aviation. There is a similar standard for automotive and railroad and industrial probably have their own variants by now, but it is never ever used in general computing. $\endgroup$ – Jan Hudec Aug 19 '20 at 5:32

The point of ADFX/ARINC 664 is that it is real time. That means the switch guarantees each type of message will be delivered in specified time according to its priority and allocated bandwidth.

For example the control computers probably need to know the inertial reference (attitude and speed) readings every 10 ms, so the switch can be configured to deliver one message from each inertial reference unit every 10 ms with at most, say, 2 ms delay (based on number of packet types with higher priority). And the switch guarantees that barring hardware failure it will deliver the messages within that delay always. That is a lot of logic on top of normal ethernet that just delivers packets on a best effort basis.

Additionally the logic also has to guarantee that if one of the units goes haywire and starts sending the packets faster than the allocated bandwidth, or starts sending jumbled packets, these errors won't interrupt any other communication going through the switch. If one inertial reference packet should be delivered every 10 ms, only one will be delivered even if the unit sends hundred of them.

And last there has to be a lot of integrity checking of the switch itself so if hardware does fail, the communication fails over to the backup network.

Since it is ethernet on the physical and data link layers, you can use plain ethernet switch for testing a component. But not for production and not for system test where you have to verify the traffic policing is set up correctly.


I haven't worked with ARINC 664/ADFX specifically, but my understanding is that aircraft use specific ADFX switches.

From Wikipedia:

Since AFDX utilizes the Ethernet protocol at the MAC layer, it is possible to use high performance COTS switches with Layer 2 routing as AFDX switches for testing purposes as a cost-cutting measure. However, some features of a real AFDX switch may be missing, such as traffic policing and redundancy functions.


Since ADFX and ARINC 664 are Layer 2 protocols, and routers operate at Layer 3, the answer to the question

How different is ADFX/ARINC 664 router from normal Router?

is easy. There is no such thing as an ADFX/ARINC 664 router, just like there is no such thing as an Ethernet router, since routers operate at Layer 3, not Layer 2. The question how something that doesn't exist differs from something else that also doesn't exist is meaningless.

  • $\begingroup$ W Mittag. Sorry I would mean switch $\endgroup$ – user1538798 Aug 19 '20 at 3:40

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