Figure 6: SDS End-to-End Encryption
Data Services
TETRA System
Boundary
Message Display Service
and Other Embedded
Aplications
PEI
End-to-End SDS Encryption
Short Data Transport Layer
(with or without SDS-TL)
Short Data Service Type 4
Standard TETRA Air Interface Encryption
and Key Management
End-to-End Key Management
NOTE:
Key Management Facility (KMF) can manage and support only one short data
association and a key at the same time.
The radio selects the E2EE mode for the outgoing text message in accordance to the address
association and requirements for the E2EE High Security Mode. Depending on codeplug settings,
you can override the address association and select using the MMI menu whether an SDS is sent to
clear or encrypted contact (Group or Private Number).
The radios support the high security mode configurable using the CPS. In this mode, the association
that binds the address to a given cryptogroup is always mandatory.
If no cryptogroup associations exist, this condition means that the keys are not loaded. In such
situation, the radio discards any outgoing or incoming message that is encrypted. You are alerted
when this situation occurs.
This feature can only be disabled using the Key Variable Loader (KVL).
2.7.9
Store and Forward
This feature allows communicating with each other without being available at the same time. If the
destination is not reachable, the message is stored in the system (if supported) until it is available or
the expiration time is exceeded. The system is configured to delete the message after a preconfigured
time and this time cannot be configured using the radio.
You can send the store and forward messages to an individual address or a group. Depending on the
codeplug settings, if you choose to send it to the group, the message status is switched from
Store
and Forward
to
Immediate
.
MN003465A01-AF
Chapter 2 : Services and Features
22
