Which deployment model offers geographic datacenter redundancy, remote failover, high availability, scale, and local failover?

Multisite with distributed call processing provides local autonomy and local failover per site but does not deliver a single unified cluster with remote failover across geographically redundant datacenters.

Dual call control is not a standard Cisco Unified Communications deployment model term and does not describe a recognized CUCM architecture.

Multisite with centralized call processing places call processing in one central location, which creates a single point of failure and does not provide geographic datacenter redundancy.

Clustering over the WAN extends a single CUCM cluster across multiple geographically dispersed datacenters connected by WAN links, allowing all cluster subscribers to participate in both local and remote failover scenarios. This model inherently provides geographic datacenter redundancy because cluster members reside in different physical locations, and the shared cluster database replication ensures high availability and scale. Local failover is achieved through co-located subscribers at each site, while remote failover occurs when a site loses all local resources.

Campus deployment is a single-site model with no geographic separation, offering no geographic redundancy or remote failover capability.