摘要 |
A redundancy arrangement for use in connection with a programmable telecommunications switch or other device. An active hardware device, such as an ISDN packet engine card, is paired with a substantially identically configured standby device. During operation, the active device, in addition to performing all of its normal functions, also advises the standby device of all events which have an effect of the operational state of the active device. By ensuring that the standby device processes the same events in the same sequence as the active device, the standby device's operational state continuously tracks that of the active device. Should the active device malfunction or be taken out of service, the standby device becomes active without significant interruption or loss of service. |