AASTRA SIP-DECT (Release 2.1)- OM System Manual - Installation, Administration and Maintenance EN - Manual (Page 178)

SIP – DECT OM System Manual Release 2.1 9 Appendix
depl-1230/1.3 Page: 178 (196)
Asterisk Asterisk is a complete Open Source PBX in software. It runs on
Linux, BSD and MacOSX and provides many features. Asterisk
supports voice over IP in many protocols, and can interoperate with
almost all standards-based telephony equipment.
Base station Please see: RFP or Radio Fixed Part
DECT Digital Enhanced Cordless Telecommunication
The standard (ETS 300 175) essentially specifies the air interface,
known as the radio interface. Voice and data can both be transmitted
via this interface.
Its technical key characteristics for Europe are:
- Frequency range: approx. 1880 – 1900 MHz (approximately
20 MHz bandwidth)
- carrier frequencies (1728 kHz spacing) with 12 time slots each
- Doubling the number of time slots (to 24) using the TDMA
process
- Net data rate per channel of 32 kbps
(for voice transmission using ADPCM)
- Voice coding using the ADPCM method
Its technical key characteristics for North American are:
- Frequency range: approx. 1920 – 1930 MHz (approximately
10 MHz bandwidth)
- 5 carrier frequencies (1728 kHz spacing) with 12 time slots
each)
- Doubling the number of time slots (to 24) using the TDMA
process
- Net data rate per channel of 32 kbps
(for voice transmission using ADPCM)
- Voice coding using the ADPCM method
GAP Generic Access Profile
- The GAP standard (ETS 300 444) is based on the same
technology as DECT, but is limited to the most important basic
features. This standard was created in order to allow telephones
of different vendors to be used on any type of DECT system. It
thus represents the smallest common denominator of all
manufacturer-specific variants of the DECT standard.
- An important limitation in the GAP standard is that external
handover is not possible. For this reason connection handover
is used, which is supported by GAP terminals.
- The operation of GAP-capable telephones is comparable to
that of analogue terminals. For example, features can be called
up via ‘*’ and ‘#’ procedures.
Handover A handover is similar to roaming, but occurs during an ongoing call.
A handover normally takes place “in the background”, without
disrupting the call (seamless handover).