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Vigor2950 Series User’s Guide
127
Note that
Dialing to a Single ISP
should be pre-configured
properly.
Basic Setup
Link Type -
Because ISDN has two B channels (64Kbps/per
channel), you can specify whether you would like to have
single B channel, two B channels or BOD (Bandwidth on
Demand). Four options are available: Link Disable, Dialup
64Kbps, Dialup 128Kbps, Dialup BOD.
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).