- Enterasys Security Router User's Guide

Asynchronous and Synchronous Support
XSR User’s Guide 10-3
Table 10-1 lists V.25bis options. By default, the synchronous port will use V25bis. The functions of
these options are nation-specific, and they may have different implementations. Refer to your
modem documentation for a list of supported commands and options.
DTR Dialing for Synchronous Interfaces
Dialer interfaces also support connections from synchronous serial lines through non-V.25bis
modems. Routers connected by non-V.25bis modems use data terminal ready (DTR) signaling
only, which can be configured in the dialer interface by issuing the
dialer dtr command in
Interface mode. When using
dialer dtr, the dial string is stored in the external device and need
not be passed to it.
Time of Day feature
A time of day feature can be configured when you use a dialer interface as a dialed backup line for
a primary leased line. When configuring the dialed backup line on the primary interface you can
issue the
time-range command to connect and disconnect the dial line during the day regardless
of traffic on the line or whether the primary line is still down.
Typical Use for Dial Services
Dial services provide WAN connectivity on an economical, as-needed basis, either as a primary
link or as backup for a non-dial serial link. Employing dial backup involves setting up a secondary
serial interface as a backup to a primary serial interface. Dial services are employed solely for dial
backup purposes, as of this release.
Ethernet Backup
Failover support is available on FastEthernet/GigabitEthernet interfaces or sub-interfaces where it
is especially beneficial for PPPoE (DSL) redundancy. The
backup interface dialer command
turns failover “on” while the
backup time-range and backup delay commands configure
intervals to keep the port up or delay bringing it up. See “Configuration for Ethernet Failover” on
page 10-40 for an example.
Table 10-1 ITU-T V.25bis Options
Option Description
: Wait tone
<Pause
= Separator 3 - national use
> Separator 4 - national use
P Dialing to be continued in pulse mode - optional parameter
T Dialing to be continued in DTMF mode - optional parameter
& Flash - optional parameter