Dect Functions - Avaya DECT R4 Installation And Administration Manual

Avaya IP-DECT System Description

DECT functions

DECT is a digital wireless technology that originated in Europe, but is now being adopted
increasingly worldwide, for cordless telephones, wireless offices, and even wireless telephone
lines to the home. DECT has been designed and specified to interwork with many other types of
network, such as the PSTN, ISDN, and GSM.
Common IP-DECT functions are handled entirely within the IP-DECT system.
Roaming and handover
The IP-DECT system supports roaming between all base stations and gateways in the system.
The IP-DECT system also supports handover if there is overlapping speech coverage.
Enhanced DECT Security
The enhanced DECT security feature is a mechanism to enhance DECT security by
introduction of early encryption and re-keying during an ongoing call. It also addresses the
security risk of staying permanently open for registration.
Early Encryption
This procedure is used for encryption of each DECT link, directly after establishment. The
purpose is to protect data like caller ID and dialed digits, exchanged before encryption with the
handsets private cipher key can start.
When a handset that supports early encryption is registered, a CKI with a corresponding DefCK
is allocated/calculated and stored both in the handset and in the IP-DECT system. The CKI
uniquely identifies the corresponding DefCK for each handset within the system. Later at each
DECT link establishment this CKI is used to identify the DefCK to be used for early encryption of
the link. The handset will release the connection in case early encryption activation is rejected.
Re-keying
This procedure periodically modifies the handsets private cipher key used for encryption of an
ongoing call. The purpose is to protect against any attempts to crack the ciphering e.g. like
super-computing.
Subscription Requirements
This procedure is used to control if registration is allowed or not. A system that permanently
allows registration will make it possible for an attacker to do over-the-air subscriptions using
exhaustive testing of AC-codes.
The subscription method "With System AC", used to allow anonymous registrations, will
permanently allow subscription attempts.
Therefore, for safety reasons, when the anonymous registration is finished change the
Subscription Method to "Disable"or "With User AC".
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Avaya DECT R4 - System Description 02/2016