Nortel Networks 1000S - Manual (Page 42)

Page 42 of 44 Configuration options
553-3031-010 Standard 3.00 August 2005
• If the master (Leader) Signaling Server is unavailable, a Follower
Signaling Server becomes the IP Telephony node master.
• Signaling Servers share telephone registrations (load-sharing).
• If a virtual trunk is unavailable, virtual trunk redundancy occurs (that is,
the call-processing software selects an alternate route).
• Signaling Servers can be configured for different types of redundancy for
their software components (for example, Alternate Gatekeeper, Failsafe
Gatekeeper).
• If the Primary Gatekeeper is unavailable, you can configure an Alternate
Gatekeeper (automatic database synchronization).
• If the Primary and Alternate Gatekeeper are unavailable, you can
configure a Failsafe Gatekeeper (at each Signaling Server).
Figure 7 on page 43 illustrates the handling of a network failure with
Survivable MG 1000S in place.