Symbol Technologies VC5090 - Manual (Page 118)

5 - 2 VC5090 Vehicle Computer Product Reference Guide
Security
The current Bluetooth specification defines security at the link level. Application-level security is not specified.
This allows application developers to define security mechanisms tailored to their specific need. Link-level
security is really between devices not users, while application-level security can be implemented on a per-user
basis. The Bluetooth specification defines security algorithms and procedures needed to authenticate devices,
and if needed, encrypt the data flowing on the link between the devices. Device authentication is a mandatory
feature of Bluetooth while link encryption is optional.
Pairing of Bluetooth devices is accomplished by creating an initialization key that is used to authenticate the
devices and create a link key for them. Entering a common PIN number in the devices being paired generates
the initialization key. The PIN number is never sent over the air. By default, the Bluetooth stack responds with
no key when a key is requested (it is up to user to respond to the key request event). Authentication of
Bluetooth devices is based-upon a challenge-response transaction. Bluetooth allows for a PIN number or
passkey that is used to create other 128-bit keys used for security and encryption. The encryption key is
derived from the link key used to authenticate the pairing devices. Also worthy of note is the limited range and
fast frequency hopping of the Bluetooth radios that makes long-distance eavesdropping difficult.
It is recommended:
•
Perform pairing in a secure environment
•
Keep PIN codes private and don't store the PIN codes in the vehicle computer
•
Implement application-level security.
Turning the Bluetooth Radio Mode On and Off
Turn off the Bluetooth radio to save power or if entering an area with radio restrictions (e.g., an airplane). When
the radio is off, the vehicle computer can not be seen or connected to by other Bluetooth devices. Turn on the
Bluetooth radio to exchange information with other Bluetooth devices (within range). Communicate only with
Bluetooth radios in close proximity.
Disabling Bluetooth
To disable Bluetooth, tap >
Disable Bluetooth
. The Bluetooth icon changes to indicate that Bluetooth is
disabled. An exclamation point appears with the icon .
Figure 5-1 Disable Bluetooth
NOTE
To achieve the best battery life in vehicle computers with multiple radios, turn off the radios that are not
being used.