ZyXEL Communications Prestige 100IH, Руководство пользователя

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P100IH ISDN Router
5-6 Remote Node Configuration
successful authentication, please make sure that you specify the correct authentication protocol when
connecting to such an implementation.
5.1.4 PPP Multilink
The Prestige uses the PPP Multilink Protocol (PPP/MP) to bundle multiple links in a single connection to
boost the effective throughput between two nodes.
Due to the fragmentation/reconstruction overhead associated with MP, you may not get a linear increase in
throughput when a link is added.
The number of links in an MP bundle can be statically configured, or dynamically determined at runtime, as
explained in the following section.
5.1.5 Bandwidth on Demand
The Bandwidth on Demand (BOD) feature adds or subtracts links dynamically according to traffic demand.
After the initial call, the Prestige uses BAP (Bandwidth Allocation Protocol) to ask the peer for additional
telephone number if BACP (Bandwidth Allocation Control Protocol) is negotiated. Otherwise, the Prestige
uses the statically configured (primary and secondary) telephone numbers of the remote node.
The configuration of bandwidth on demand focuses on the Base Transmission Rate (BTR) and the
Maximum Transmission Rate (MTR). The relationship between BTR and MTR are shown below:
Table 5-2 BTR v MTR for BOD
BTR & MTR Setting No. of
channel(s)
used Max No. of
channel(s)
used Bandwidth
on demand
BTR = 64, MTR = 64 1 1 Off
BTR = 64, MTR = 128 1 2 On
BTR = 128, MTR = 128 2 2 Off
When bandwidth on demand is enabled, a second channel will be brought up if traffic on the initial channel
is higher than the high
Target Utility number for longer than the specified Add Persist value. Similarly,
the second channel will be dropped if the traffic level falls below the low Target Utility number for longer
than the Subtract Persist value.
The Target Utility specifies the line utilization range at which you want the Prestige to add or subtract
bandwidth. The range is 30 to 64 Kbps (kilobits per second). The parameters are separated by a ‘-’. For
example, ‘30-60’ means the add threshold is 30 Kbps and subtract threshold is 60 Kbps. The Prestige
performs bandwidth on demand only if it initiates the call. Addition and subtraction are based on the value
set in the
BOD Calculation field. If this field is set to Transmit or Receive , then traffic in either
direction will be included to determine if a link should be added or dropped.
Transmit
will only use