Company XYZ wants to redesign the Layer 2 part of their network and wants to use all available uplinks for increased performance. They also want to have end host reachability supporting…

TRILL uses IS-IS to route Layer 2 frames between RBridges, enabling all uplinks to forward traffic simultaneously in an active/active fashion without requiring port-channel aggregation. It supports conversational learning, where RBridges learn end-host MAC-to-RBridge mappings directly from observed data-plane traffic, satisfying the requirement for end-host reachability through conversational learning.

LISP is a routing architecture that separates endpoint identity from location for Layer 3 mobility and does not provide Layer 2 active/active multipathing.

MSTP improves on legacy STP by mapping VLANs to spanning tree instances, but it still blocks redundant ports and cannot achieve active/active forwarding on all uplinks.

A switch stack presents multiple physical switches as one logical device but still requires port-channel or similar aggregation to use multiple uplinks simultaneously, which the design constraint prohibits.