Product Specs

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be exchanged using the bonding procedure, but that does not mean they are bonded if

the keys are not stored and used the next time.

If a device is bonded with another device, like a heart rate monitor and a smartphone,

they can encrypt the connection without exchanging any sensitive security information.

When the smartphone connects to the heart rate monitor, it can just issue a ‘turn on

encryption’ request, and both sides will use the keys already stored, so nobody

snooping can see a key exchange and therefore decode the messages being sent, as is

done when pairing.

Certificate

Standard BLE does not use certificates for setting up a secure connection between the

master and slave, the KeySafe enabled E-RL 2 does however use certificates signed by

the cloud certificate authority KeySafe for setting up secure connections or creating

secure relationships. Without the certificate handover by the master (e.g. smartphone)

and positive outcome of the verification the E-RL 2 will not allow any device to pair,

all pairing requestes by the master will be rejected with an insufficient authentication

error code. When the certificate is accepted by the E-RL 2 it will initiate the setup of a

secure link between the devices and allows the user to input the 6 digit passkey on

older smartphones or on the more modern smartphones allows the app to input the 128

bit passkey for the user automatically. Entering the passkey is only required once

during pairing and bonding, all other times the smartphone will remember the saved

bonding information and connects flawlessly with the E-RL 2 until the certificates time

has expired. Both the certificate and passkey are provided by the KeySafe cloud

service upon requesting for an eKey. Next to the standard pairing and bonding the use

of the KeySafe cloud API also does offer a secure relationship based on OTP (one-

time-pass) commands. Using OTP’s does not require the mobile device to pair and

bond to securely command the lock to operate. The advantage is trivial, no need to

enter passkeys or solving the many problems related to pairing and bonding in many

iOS and Android smartphones due to software bugs in the smartphones BLE stack or

software version specific particularities. The exact process of requesting, processing

and handling eKeys and OTP’s is explained in more detail in the KeySafe-Cloud end

node API documentation.

1.1.7 Radio Communication

Classic and Bluetooth LE operates in the 2.45 GHz band which it shares with Wi-Fi,

Zigbee and microwave ovens worldwide!. Bluetooth LE still retains its fundamental

resilience by splitting its radio traffic across 40 channels as shown below (Figure 6).