Lancom 1723 VOIP User Manual page 13

LANCOM 1722 VoIP – LANCOM 1723 VoIP – LANCOM 1724 VoIP – LANCOM 1823 VoIP
Chapter 1: Introduction
To satisfy the strongly increasing demand for higher bandwidths, the stand-
ards ADSL 2 and ADSL 2+ provider higher data rates as a basis for applica-
tions such as video streaming or high-definition TV (HDTV) over the Internet.
Depending on the Internet provider, ADSL 2 devices support downstream data
rates of up to 12 Mbps, and ADSL 2+ devices support up to 24 Mbps. Hand-
shake routines during connection establishment ensure that the standards
ADSL, ADSL 2 and ADSL 2+ are intercompatible.
Parallel to data transfer, ADSL also provides full and unlimited support for the
classic applications in telephony (telephone, fax, answering machine, PBX).
This is facilitated by splitters which separate the voice frequencies from the
data frequencies.
The LANCOM VoIP Router features an integrated modem for ADSL/ADSL 2+.
It can be directly connected to the splitter with the supplied cable.
ADSL can operate over both ISDN- and analog telephone lines (POTS – Plain
Old Telephone Service). Devices with an integrated modem are supplied in
two versions. Information about the supported telephone system is to be
found on the type designation on the underside of the device. The device
name is marked on the label along with a suffix which indicates the supported
telephone system:
Suffix
'Annex A'
'Annex A'
Annex A-type devices are exclusively to be operated at ADSL-over-POTS con-
nections. Annex B-type devices are exclusively to be operated at
ADSL-over-ISDN connections. Your network operator will be able to inform
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INTERNET
Splitter
PSTN
Supported telephone system
ADSL-over-POTS
ADSL-over-ISDN
ISDN
NTBA
ISDN Phone
Splitter
ADSL Router LAN