HP ProCurve Secure Router 7203 dl Advanced Management And Configuration Manual page 95

Option Demand Routing
supported hardware • analog and BRI backup modules, which can
• two-port ISDN modules, which are installed
applications • backup modules—backup WAN connection
• two-port ISDN modules—WAN connection
Data Link Layer PPP, which is configured through the demand
protocol interface
initiation of dial-up • backup connection—established when two
connection
• primary ISDN connection—established
termination of dial-up • backup connection—terminated when pri-
connection
• primary connection—terminated when no
methods to limit usage • configure the access control list (ACL) to
of dial-up connections
• adjust idle timers to match the time intervals
increasing bandwidth • no bonding or MLPPP support for ISDN
• MLPPP support for two-port ISDN modules
Table 3-1. Differences Between Demand Routing and Persistent Backup
Connections
be installed on top of any narrow module
in a narrow slot on the ProCurve Secure
Router
for two offices that require high availability
but need to limit usage and costs
between two offices that exchange data
periodically and need a low-cost WAN
solution
conditions are met:
– primary connection is unavailable
– "interesting" traffic needs to be
transmitted
when "interesting" traffic must be
transmitted
mary connection is re-established or when
no interesting traffic is received before the
idle timer expires
interesting traffic is received for the time
specified in the idle timer
limit "interesting" traffic, which triggers the
ISDN connection
for which your company is charged for its
dial-up connection
backup modules
Configuring Backup WAN Connections
Determining a Backup Method
Persistent Backup Connection
analog and backup modules, which can be
installed on top of any narrow module
backup for two locations that must maintain
a constant WAN connection
PPP, which is configured through a PPP
interface
backup connection established immediately
when the primary connection fails and
maintained until the primary connection is re-
established
terminated when primary connection is re-
established
specify times, such as weekends and eve-
nings, when the dial-up connection should
not be established (even if the primary
connection goes down)
channel bonding with another ProCurve
Secure Router
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