Honeywell Mark III - Manual (Page 24)

HONEYWELL Aerospace Electronic Systems Page 24
Use or disclosure of information on this page is subject to the restrictions on the title page of this document.
support as part of the baseline the text Weather uplinks which has become standard use within the Air
transport industry.
ATN
The industry has embarked on the definition of a new communications standard named the Aeronautical
Telecommunications Network (ATN). The ATN offers a standardized, robust, and efficient communications
mechanism that provides additional services. Honeywell has been a leading member of the international
consortium, Aeronautical Communication Inc. (ACI) developing this new communications software. The ATN
is the ICAO defined solution to be used world wide as the industry transitions much of today’s ATC voice
communication to datalink in the years ahead.
ACI has developed both the Router Reference Implementation (RRI), which is the communications stack,
and the Application Service Elements (ASEs), which are the algorithmic portion of the CNS/ATM-1
applications. ASEs have been developed for Controller Pilot Data Link Communications (CPDLC), Automatic
Dependent Surveillance (ADS), Context Management (CM) and Flight Information Services (FIS). ACI
developed both the RRI and the ASEs to be portable and therefore readily hostable in a number of different
target environments, both in avionics and ground systems. An integrator would only have to port the RRI &
ASEs to the target environment and then add the display portion of the applications along with subnetwork-
specific interfaces (see Figure 9).
Figure 9 ATN
As the only CMU manufacturer involved in the actual development of the ATN software, Honeywell provides
our customers with a unique capability of having engineering and technical support as this new technology
is fielded in the years ahead. The Mark III CMU was specifically developed to support the addition of this
new ATN software, without any hardware modifications to the unit. This will be a future upgrade option for the
Mark III CMU.
Encryption/Authentication
Encryption and authentication are key issues surrounding secure data communications. Encryption involves
the encoding of the broadcast bit stream using a secure encryption key. Authentication involves ensuring
that only authorized users are accessing the application services. The Mark III CMU is designed to support
RRI
ASEs
Applications
Subnetworks