Product manual

System description, DECT air interface
Technical Product Manual - DCT1800-GAP
TD 92093 (1/LZBNB 103 108 R4D) / 2006-03-09/ Ver.C
© 2006
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• Portable part to portable part direct communication (private)
Having access rights does not automatically imply that a portable part can place a call. It may be
requested to authenticate which is part of the security services. This protects the owner or operator
from unauthorized or fraudulent use of the network. During a call a portable part may be requested
to authenticate; a fixed part sends a random number to the portable part and based on this random
number the portable part must provide a correctly calculated number to prove its authenticity.
6.7.1 Access rights to different fixed parts by the same portable part
All fixed parts frequently broadcast a globally unique (to a service provider) Access Rights Identity
(ARI) (see paragraph
6.7.3). Every portable part has one or more Portable Access Rights Keys
(PARKs) and an International Portable User Identity (IPUI). They operate as a pair.
One PARK relates to one or more ARIs depending on the number of ‘don’t care bits’ (see figure 33).
For example, if the last two bits of an ARI are ‘don’t care bits’ the PARK (portable part) has access to
4 fixed parts. In other words, with one subscription the cordless phone has access to 4 DECT systems
of a service provider.
The number of significant bits of a PARK (PARK (y)) are specified by the parameter Park Length
Indicator (PLI). PARK, PLI and IPUI are downloaded into the portable part during the subscription
process. PLI is used in mobility systems as cordless phones must be registered in groups of radio
exchanges. Otherwise mobility can not be supported by the cordless phone.
Fig. 33 ARI, PARK and PLI
The portable part periodically compares the received ARI with its PARK. If the result is positive the
portable part is allowed to access the fixed part. The IPUI is used to identify the portable part in the
domain defined by its related ARI. This IPUI can either be locally unique or globally unique.
A locally unique IPUI has a validity domain restricted to one particular DECT network, such as a PBX
or a LAN. These identities are therefore restricted to be used only in that network. These identities
are normally not connected to a subscription.
A globally unique IPUI has no restricted domain by itself. Any restrictions for usage of this identity has
to do with the access rights (PARK) that is related to the identity. A globally unique IPUI is normally
related to one or more subscriptions.
The same portable part can have access to several different types of systems if equipped with the
relevant PARKs and associated protocols. It is not a common protocol for all systems that provide
intersystem roaming, but it is the portable part equipped with access rights and related protocols to
the wanted systems.
ARI
PARK (y)
Don't care bits
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