F5 Load Balancer terminology

GTM – Global Traffic Manager – DNS based load-balancer, used for cross-DC traffic routing

LTM – Local Traffic Manager – TCP/UDP based load-balancer, typically used in a single DC for multi-server load balancing

CA – Continuous Availability – A vRealize Operations feature which enables you to stretch a cluster across two DCs

FD – Fault Domain -  A group of vRealize Operations nodes residing in a single DC. CA supports up to 2 DCs or 2 FDs