Ip Routing Overview - 3Com 3C421600A Management Manual

94 C 7: LAN-
HAPTER TO

IP Routing Overview

-LAN R
OUTING
Dial-Out Scripts
All dial-out users can have dial-out scripts defined in the user profile. The
dial-out script can consist of up to six send/receive pairs. The script can
contain AT commands and other login commands needed to access the
remote location.
The command providing this function (set dial_out user) overrides
the phone number and alternate phone number values specified in the
set user command.
Bandwidth Allocation with MLPPP
The RAS 1500 can provide variable bandwidth automatically, depending
on the amount of traffic, with Multilink Point-to-Point Protocol (MLPPP).
Every five seconds, MLPPP samples network traffic. From these samples,
the RAS 1500 calculates the percentage of channel utilization. If the
percentage is higher than the expansion value you specify, the RAS 1500
brings up an additional B-channel. If, on a second sample, line usage
drops below the decrement value you set, the RAS 1500 drops the
additional B-channel. The sampling interval cannot be modified, but you
can configure expansion and decrement thresholds to meet your system
needs.
Numbered and Unnumbered Interfaces
Either a numbered or an unnumbered interface can be used when setting
up a wide area network (WAN) link. Using an unnumbered link helps
conserve IP addresses. Using a numbered link requires unique IP addresses
assigned to each side of the WAN link.
For an unnumbered link, the unnumbered interface may be associated
with the IP address of, for example, the Ethernet interface of the router.
Table 19 Interface Types and Defaults
Type
unnumbered
numbered
Default
the rm0/eth:1 IP address of the RAS 1500. Using this interface
saves IP addresses
the specification of an address for each end of the link