Security; Bluetooth Configuration - Motorola MC21XX SERIES User Manual

4 - 2 MC21XX Series User Guide
The Bluetooth radio in this MC2180 operates as a Class 2 device power class. The maximum output power is
2.5mW and the expected range is 32.8 feet (10 meters). A definition of ranges based on power class is difficult
to obtain due to power and device differences, and whether one measures open space or closed office space.
NOTE It is not recommended to perform Bluetooth wireless technology inquiry when high rate 802.11b
operation is required.

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 occurs 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.
Recommendations are:
•
Perform pairing in a secure environment
•
Keep PIN codes private and don't store the PIN codes in the mobile computer
•
Implement application-level security.
The Microsoft stack supports Smart-pairing. For detailed information, refer to the Microsoft MSDN.

Bluetooth Configuration

The services supported by the Microsoft Bluetooth stack:
•
Generic Access Profile
•
Serial Port Service
•
Service Discovery Access Profile
•
Dial-Up Networking Profile (Client)
COM5 and COM9 ports are available for the Microsoft Bluetooth stack.