GSMK CRYPTOPHONE G10i, Руководство пользователя

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pleted you hear a »Ping« sound and can start talking to your partner.
In order to verify the authenticity of the key, please take a look at the
display and read the three letters under »you say« to your partner and
verify the three letters under »partner says«. The green SECURE indica-
tor is only visible when a secure call has been established. During all
other times it is shown in grey with an open lock.
Key Verification
Reading the three letters and verifying what your partner says is meant
to protect you against so-called ‘man-in-the-middle attacks’ on the se-
cret session key. The session key is different for each call, as no key ma-
terial is re-used between calls. The letters are mathematically derived
from the unique secret key that is generated for each call. By reading
and verifying them with your partner, you make sure that you are in-
deed communicating using the same key. Please pay attention to the
voice of your partner when he reads his three letters. To be completely
on the safe side against very sophisticated voice impersonation during
the key verification, you could periodically reverify the letter code with
your partner during the conversation.
SECURE
you say: partner says:
CTQ
DGA