Switch User's Guide

About the CSX400

CSX400 and CSX400-DC User’s Guide 15

ISDN Back-up

The ISDN back-up feature provides a back-up link for a remote site or branch ofﬁce when one or

more primary WAN interfaces for a frame relay circuit or a nailed-up PPP connection fails. The

WPIM-S/T serves as the backup medium for this primary connection. The WPIM-S/T uses the

ISDN interfaces to back-up any primary interfaces which have been conﬁgured for ISDN back-up.

Time to Connect, Time to Disconnect, Connect Retries, Back-up Override, Input Idle Time-out

and Output Idle Time-out, are the six back-up parameters used to manage the ISDN Back-up

feature on the CSX400, and are described as follows:

Time to Connect — Time to Connect allows you to conﬁgure the amount of seconds the primary

interface can be in a failed state, before attempting to switch over to the back-up interface.

Time to Disconnect — Time to Disconnect allows you to conﬁgure the amount of seconds the

restored primary interface must remain connected, before attempting to switch over from the

back-up interface.

Connect Retries — Connect Retries allows you to conﬁgure the number of tries to restore the

back-up interface, before giving up.

Backup Override — Backup Override forces the back-up interface to remain connected, and

does not allow the back-up interface to switch back to the primary interface, even if the primary

interface is restored.

Input Idle Time-out — Input Idle Time-out allows you to determine the amount of time necessary

for data packets to be received, before the interface is automatically disconnected.

Output Idle Time-out — Output Idle Time-out allows you to determine the amount of time

necessary for data packets to be transmitted, before the interface is automatically disconnected.