Draytek VigorIPPBX 2820 Series, User Manual

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VigorIPPBX 2820 Series User’s Guide 268
PPP Authentication - It specifies the PPP authentication
method for PPP/MP connections. Normally you can set it
to PAP/CHAP for better compatibility.
TCP Header Compression - VJ Compression : It is used
for TCP/IP protocol header compression. Normally it is
set to Yes to improve bandwidth utilization.
Idle Timeout - Because our IDSN link type is Dial On
Demand , the connection will be initiated only when
needed.
Bandwidth-On-Demand
(BOD) Setup Bandwidth-On-Demand is for Multiple-Link PPP
\(ML-PPP or MP). The parameters are only applied when
you set the
Link Type to Dialup BOD . The ISDN usually
use one B channel to access the Internet or remote
network when you choose the Dialup BOD link type. The
router will use the parameters here to decide on when you
activate/drop the additional B channel. Note that
cps
(characters-per-second) measures the total link utilization.
High Water Mark and High Water Time - These
parameters specify the situation in which the second
channel will be activated. With the first connected
channel, if its utilization exceeds the High Water Mark
and such a channel is being used over the High Water
Time, the additional channel will be activated. Thus, the
total link speed will be 128kbps (two B channels).
Low Water Mark and Low Water Time - These
parameters specify the situation in which the second
channel will be dropped. In terms of the two B channels,
if their utilization is under the Low Water Mark and these
two channels are being used over the High Water Time,
the additional channel will be dropped. As a result, the
total link speed will be 64kbps (one B channel).
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I
I
P
P
P
P
B
B
X
X
IP PBX
（
IP -Private Branch eXchange
）
is a private telephone network used within an
enterprise. Users of the PBX can share a certain number of outside lines for making
telephone calls external to the PBX.
IP PBX integrates the benefits of VoIP and transfers the message from IP phone into the data
that can be accepted by traditional PBX through IP network. It is a new platform that
enterprises can use data network to deliver voice. Additionally, to move the IP phone set(s),
users just need to plug into another network connector. Such thing simplifies the procedure
of moving, increasing, changing and deleting phone settings; also it can join with other
system such as CALL center to be a multi-functional communication platform. Moreover, it
can save large cost in communication for the enterprise.