What is OTAR ?
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OTAR
Without OTAR, the operator has to collect all radios
and reprogram them to change the keys. Or a
technician must go around and visit all the radio
sites with a PC and a programmer just to change
keys – it is time-consuming.
What is OTAR ?
OTAR or Over-The-Air-Rekeying is the common name
for the method of changing the encryption keys over
a radio channel or “over the air”. It is also referred to
as Over-the-Air Transfer (OTAT).
Regular key changing is one of the basic
In addition, without OTAR, it is very difficult or even
impossible to re-program the scramblers with a
wired programmer due to their big number and
distances of one from another.
OTAR solves all these problems - you can do without
reprogramming all the radios and visiting the radio
sites. You can easily and briskly update the keys or
requirements for secure radio communication. Key
changing can be achieved by reprogramming of
scramblers with a wired programmer or over the air.
Presently radio communication systems, secured by
scramblers, prefer to use the OTAR method of key
changing due to the following benefits.
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change them over completely regardless of the
distance and big numbers.
To make the most of these benefits, leading
manufacturers of scramblers began to design
various methods of key changing over the air.
Many of the newer NSA (National Security Agency )
cryptosystems that use the 128 bit electronic key
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Benefits from using OTAR
Brisk and efficient – these are the words to describe
the benefits from using OTAR.
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The operator can change over the keys of many
radios at the same time regardless of the distance.
cryptosystems that use the 128-bit electronic key,
such as the ANDVT, KY-58, KG-84 A/C, and KY-75
are capable of obtaining new or updated key by
OTAR. All an operator would have to do is to observe
the alarm indications and ensure the alarm indicator
returns to operate. The electronic key would normally
come from the Net Control Station (NCS).
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IC F9011
i ll i l d th OTAR
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The keys which are consisted of big numbers can
be easily changed or updated without manual
programming.
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The use of OTAR drastically reduces the
distribution of physical keying material and the
physical process of loading crypto equipments with
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The current IC-F9011 series all include the OTAR
function. (OTAR function became available from the
firmware Rev.1.40 on.)
key, therefore it can save cost. A station has
nothing to do with actual physical CRYPTO
changeovers on a day-to-day basis.
The dispatcher
Old key
New key
Update or change Electronic
keys remotely
OTAR or Over-The-Air-Rekeying enables
enters the new key.
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OTAR or Over-The-Air-Rekeying enables
the operator to update the current
electronic keys or change them over with
the new keys remotely.
