Installation manual

Showtime
Jargon for the ADSL state (that may be signalled by a green ‘line’ LED being permanently on
rather than flashing) equivalent to the ‘CD’ LED or ‘CONNECT’ message from a modem.
May mean (if you’re unlucky and the line is bad) that you have a 32kbps connection to the
DSLAM in your local exchange, since this is normally the ‘minimum’ speed defined as
‘acceptable’. Note that this does not mean you can get past the DSLAM and transmit any data;
for a useful connection you need to be using the correct ATM VPI/VCI and the correct
encapsulation across the ADSL link. Of course, this is not part of the ADSL specification.
Advice: Set for the CopperJet 81x with firmware version 4.17 or higher the
Line Modulation on Multimode
Splitter
Filter with a low pass (telephone) socket and a high pass socket which is used to connect to the
ADSL modem. At the local exchange another splitter is connected to the telephone network
(low pass) and the DSLAM (high pass)
Synchronisation and Training
This is the modem initialisation process defined by the G.994.1 (G.hs handshaking)
recommendation. This process, if successful, ends in the state known as ‘showtime’.
VPI/VCI
The ATM Virtual Path Identifier (VPI) and Virtual Channel Identifier (VCI) uniquely identify a data
path on an ATM link. An ATM switch (or other device incorporating ATM switching capability
like a DSLAM or BAS) can be configured to take data from one VPI/VCI on an incoming link and
map it to another VPI/VCI on an outgoing link.
This configuration defines the route through the ATM switch. Note that this means that a
particular data connection may be given many different VPI/VCI ‘addresses’ as it passes
through the network.
Allied Data Technologies 51
CopperJet 81x
CJT 81x 02-10-2001 11:45 Pagina 51