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I tried to understand the data protocols used to connect InFlight-Entertainment (IFE) Server, Seat Electronic Unit (SEB), Floor Disconnect Box (FDB) and Seat Display Unit (SDU), but I'm a bit struggling about this.

Generally speaking I've seen that the most used transmission protocols for avionics are ARINC 429 (629 in case of Boeing 777) and ARINC 664 or AFDX, since part of the IMA infrastructure, and in other rare case ethernet connections, however I haven't found particular specifications about this particular connections.

Does anybody know something about this or have good sources from which start back my research?

Federico
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Bluephoenix
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  • @Gerry can you tell me, at least with the companies you have mentioned before, which protocols/standards you have found there? – Bluephoenix Oct 17 '17 at 07:28
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    I don't know the streaming protocols used. It's been almost 10 years since I had any contact with them. The system was basically a server with Ethernet distribution. Since airline seat configurations change, you need some flexibility in connections. Think of the FDB as a router/connection point for nearby seats, the SEB as a media client (PC, XBOX, etc.) and the SDU is just a monitor. – Gerry Oct 17 '17 at 12:30
  • Is there a specific aircraft you are focusing on? That might help narrow down what IFE system(s) might be used. ARINC 429 isn't a good fit for IFE. – selectstriker2 Oct 17 '17 at 13:35
  • @selectstriker2 I'm not focused in a specific aircraft but instead in a specific IFE brand, Panasonic. – Bluephoenix Oct 17 '17 at 13:42
  • I have not worked with IFEs, just certified avionics, but I suspect that most IFEs uses a centralized server, running some consumer OS such as Windows or Linux. They would then just use an Ethernet protocol such as TCP/IP to communicate. Related to your question: https://aviation.stackexchange.com/questions/15604/how-does-the-in-flight-entertainment-system-works – selectstriker2 Oct 17 '17 at 13:58
  • @selectstriker2 It could be possible indeed but actually ethernet protocols doesn't ensure any kind unidirectionality pretections, if I understood correctly from avionics litterature ARINC protocols are also used for security reasons. In a recent search I found out something about ARINC 628 protocol (part 2 and 3) used specifically for IFE communications in Boeing. Still I ask myself if is it possible to have other ARINC protocols used to connect IFE components like FDB, SEB, SDU together and in case which ones. About the link I had already read it before writing the question. – Bluephoenix Oct 17 '17 at 14:16
  • @Gerry Thx for your experience feedback, I'll check more information based on this. – Bluephoenix Oct 17 '17 at 14:17
  • This might be a useful resource as far as what ARINC (the organization) is working on for IFE http://www.aviation-ia.com/aeec/projects/cabin_systems/index.html. Not that any of that has to be used for any IFE. It is also important to note that not all ARINC standards are data protocols. ARINC 429 is in no means secure, but it is simple to implement into certified avionics. – selectstriker2 Oct 17 '17 at 14:20
  • @selectstriker2 So is it possible to not have at all ARINC protocols inside IFE and having just an ARINC protocol that connects IFE to the CIDS or the CMS? – Bluephoenix Oct 17 '17 at 14:33
  • It is technically possible to have no ARINC defined protocols in use, as nothing regulatory mandates their use. ARINC 429 is a common avionics data bus because it has mainstream adoption all over the aircraft. IFE isn't safety critical and isn't held to the same stringent software development guidelines (DO-178), or could simply be identified as DO-178C DAL E, which has no safety impact and can just use company design standards. The goal of IFE vendors is to design it as cheaply and quickly as possible to keep up with the consumer media tech as @Gerry stated. – selectstriker2 Oct 17 '17 at 14:50
  • @selectstriker2 Ok but as it was shown but some notable security experts, from IFE is still possible to bring damage to the aircraft services, even though not to the critical ones. This is why I'm looking for information about the current IFE ecosystem, to understand better which is the impact of an attack brought from the IFE. – Bluephoenix Oct 17 '17 at 15:05
  • I assume you are referencing this (or similar) articles: http://www.eweek.com/security/security-vulnerabilities-found-in-airline-entertainment-systems. It is important to note that the IFE system does not interface with the flight systems in any way, so short of turning of the cabin lighting or suddenly getting all of the speakers to play some noise, I'm not sure what damage compromising the IFE system a hacker would hope to cause. – selectstriker2 Oct 17 '17 at 15:22
  • @selectstriker2 Actually you cannot do nothing that interfere with Aircraft Control Domain and even Airline Information Services Domain, but from what I've understood some features like lighting management, audio, EVAC signal and even maybe oxygen maks are deployed in CIDS, that is nearly connected to IFE from what I've found, so you can create a fake "attack" to cause panic to the passengers. Am I wrong? Plz in case tell me if I did wrong assumptions somewhere :) – Bluephoenix Oct 17 '17 at 15:39

1 Answers1

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Airbus IFE system

All data sources and servers are concentrated in the IFE Center which delivers them to the cabin LAN using Ethernet. The LAN itself is Ethernet.

Some data are received by the IFE Center from the Cabin Intercommunication Data System which is itself connected to AFDX (Ethernet, ARINC 664) ADCN network.

The cabin network then distributes data and power to overhead displays and seat IFE units.

Schematic:

enter image description here
Source, page 15

Architecture:

enter image description here Source, page 15

IFE System for the A350

The IFEC rack is the source for all data sent to the passengers IFE units and the flight attendants panels. It contains files and media servers, is linked to external cameras (ETACS), landscape cameras and SATCOM.

  • IFE: In Flight Entertainment
  • IFEC: In Flight Entertainment Center. A system with redundant sources and redundant outputs.
  • ETACS: External and Taxiing Aid Camera System
  • SATCOM: Satellite Communications

The IFEC is also interfaced with the CIDS which supply it with data from systems like CDAU and ADIRS and other aircraft systems using AFDX, engine data from PCS, or discrete signals like cabin systems (oxygen) or public address.

  • CIDS: Cabin Intercommunication Data System, the main way for attendants to control the cabin systems other than IFE.
  • CDAU: Centralized Data Acquisition Unit
  • ADIRS: Air Data/Inertial Reference System
  • AFDX: Avionics Full Duplex Switched Ethernet (ARINC 664)
  • ADCN: Avionics Data Communication Network
  • PCS: Propulsion Control system

IFE power is supplied by some SPDB.

  • SPDB: Secondary Power Distribution Box

The IFEC and SPDB are controlled by ICPs, FAPs, CWSs and RCCs.

  • ICP: Integrated Control Panel (in cockpit)
  • FAP: Flight Attendant Panel
  • CWS: Cabin Work Station
  • RCC: Remote Control Center

The IFEC delivers data (audio, video, other data) as Ethernet frames to FDBs using a switch. There are actually two or more IFEC switches, each one feeds some FBDs.

FBDs also receive power from the SPDB. Ethernet frames and power are distributed by FDBs to overhead displays and IFE units.

  • FDB: Floor Disconnect Box. Used as a switch to create the network. FDB ensure network redundancy: Each FDB receives data from one IFEC switch, but as FDB share the same network, IFEC is still available when one of its switch is failed.

Each seat gets its IFE unit which is connected using a SEB. The IFE unit encompasses the SDU, the PCU and headset.

  • SEB: Seat Electronic Box. A network interface card, with power management.
  • SDU: Seat Display Unit (touch screen in front of the passenger)
  • PCU: Passenger Control Unit (interface)

The big picture:

enter image description here
Source

Security aspects

Your question was motivated by the security aspects of the cabin network vs. the other aircraft domains (e.g. avionics or cabin systems).

For Airbus, the cabin IFE network is only a layer 2 LAN with multiple Ethernet segments linked by Ethernet switches. There is no possibility to route malicious packets to other domains, since there is no routable (layer 3) protocol.

The interconnection between IFE and other systems is made through the CIDS, which is based on a redundant "director" which controls data destination. Without other elements, the assumption is security is primarily at CIDS level.

More information in this presentation (some pages are in German, most are in English).

mins
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